Mustang Misfire Under Load

It runs better but still. 3 z71, 148k miles, and brand new tranny (condition existed both before and after tranny rebuild) on acceleration in 1st or second gear (dont usually get 3rd gear to 3000 rpm) when i get to around 3000 rpm the engine stumbles real bad. I got one of those in a few weeks ago. I have a 1997 Ford F-250 4x4 with a 4. Different owners seem to describe this problem using a variety of expressions. Misfiring after installing a thread insert in cylinder 3. Need help with intermittent engine sputter and loss of power My 1986 fuel-injected 5. It seems like an ignition problem, like its on and off running on 7 cylinders only under load, and missing. Mustang DTC Codes. However, many 3. Can You Drive with a Blown Head Gasket?. Did everything you did; swapped coils, plugs, and injectors hoping for the best. I also feel the misfire under load. 25 with a zetec engine. what happens if you clean inside the maf with like carb cleaner and try it. | Find answers to your 2006 Ford Mustang GT question from certified mechanics and auto experts. The misfire code was actually caused by the common problem of restricted EGR ports on this engine. It should still be under. My problem is a bad (and getting worse) intermittent misfire, especially @ 1500-2000 rpm under load, but also can feel it at idle. How much can a repair cause? It depends on the cause. Car was running fine - Ford 1966 Mustang question. Code reader says multi cylinder misfire. I replaced plugs with OEM and OEM WIRES new distributor and cap and rotor. The 2011 Ford Escape has 4 problems reported for misfire under load. If the misfire is happening randomly it may cause a check engine light to stay on and display the code P0300. I just bought a '02 Mustang 3. About 3 months ago she developed a miss. Originally, I diagnosed and repaired a P1136 code by replacing the bank 2 camshaf sensor. Ok here goes. When I start up a hill or just push the pedal to the floor it has an occasional miss. Forced induction engines may need gaps as small at 0. These engines, in both a Sable and Taurus, are notorious for faulty ignition coils. Recently we came across a 2005 Ford F150 with a 5. The ignition coil/module receive there voltage directly from alternator. If the frequency of misfire is high the Powertrain Control Module (PCM) may place the engine in "Limp-In" mode. (1) 2" Grade 8 3/8" coarse thread Bolt (29 cents)(1) Grade 8 Nut for above (2) Washers for above (1) 10" length of 10 or 8 gauge stranded-core electrical wire. If I accelerate, or run at a higher RPM, it goes away. Craig's Ford 289 Motor misfiring ! Adjusting timing and mixture on your classic carb 66 Mustang 1966 Mustang Coupe - Day 54 How to diagnose a misfire that isn't ignition related. 5 300TDI Auto with 94,000 miles on the clock. Never heard of Arco and we dont have any I know of in NY but I have gotten bad gas in an old Lightning of mine. check engine light started flashing. it has new plugs and wires and spark to each cylinder the plugs are turning black already so it is running rich and the #4 cyinder is by far the worst it was wet when i pulled it. I noticed on the freeway I my truck was a little rough from the engine and I got off and it was idling rough too. I've tried replacing the fuel filter several times and currently have the gas tank off thinking that it might have rust or gunk that is fouling the lines. I took it to a friend's shop and put it on the code. If you leave the connector on spark plug 4 and you move the coil and the misfire moves to cylinder 2 (or the misfire moves maybe to cylinder 3, but I don't think that can happen), then the coil is bad. The car was idling rough but drove fine with the exception of a hicup here and there while accelerating. Mode $06 is a PCM and scan tool diagnostic mode that may or may not be familiar to you. Any ideas? I also changed the low side fuel pressure sensor with no luck. I experience this phenomena when it's cold as well. How a torque converter lockup works. I had a strange misfire under load. I've been experiencing misfires under load. Lean misfire can also be caused by an EGR valve that is stuck open or is not closing fully. The valve was removed either in april 2002 for vulcans and may 2002 for duratec's. Increasing the "coil saturation" time (the time the voltage to the coil is on to build up its magnetic field) increases the coil output voltage at high rpm when misfire is most apt to occur under load. Stinger-Performance. The faulty component was causing off-and-on issues with the cruise-control system and resulted in an intermittent "flutter" while driving, which made it feel like the engine was cutting out for a second or so (fortunately this only happened every couple-hundred. 2001 expedition 4. If you have a friend that has a Ford IDS or a scope that can look at the ignition firing you can pinpoint it. It happens in overdrive and when the engine is put under load at around 2000 rpms or 65 to 70 mph. A few misfires are to be expected under these conditions, and should cause no major performance problems or significant increase in emissions. Nobody looks forward to seeing that annoying orange check engine light on their gauge cluster light up like a street light. I won't mention your choice of plugs but go get a set of the correct autolite or motorcraft. New problems today. This allows more energy to reach the plugs so they fire more reliably under all conditions. It didn't affect the drivability, but it was quite noticeable on the freeway. In the beginning there were also P00171 and P00174 codes, (too lean bank 1 and 2). I brought it to a garage and their "computer" SAID I HAD A SERIOUS Misfire on Cyl 4 and an "odd reading" on cyl 8. Hey guys im stumped, the other day driving down the freeway the tundra started to rattle and loose engine power. So everyone on hear that says a weak battery cannot cause a misfire is wrong especially with a Subaru!!! I recently ran into this exact same problem with my 2013 Subaru Impreza 2. I have a random misfire under medium to heavy load, I am pretty sure its cyl 6. What would cause the engine check light to flash on a 1997 ford f150? If the check engine light is flashing at 1 second intervals , an engine. Misfire at low RPM and when engine is under load. Q: I have an 88 mustang with a new cam, springs, coil, distributer, fuel pump, spark plugs, wires, timing chain and I'm having a sputter problem if I go over 3500 rpm and if I keep pushing it it will backfire. I have an '02 Envoy, 4. Finally, pop off a valve cover and have a close look at the valve train for any obvious damage. As to why the system could not recognize the misfire, I have no idea. Defective ignition wires, restricted injectors, or. I get to my destination where Im doing a bunch of work (headers, exhaust, tune, short throw shifter, transmission fluid, thermostat) and drive back. A misfire alone doesn’t necessarily mean that a rocker arm has suddenly fell out of place. Need help with intermittent engine sputter and loss of power My 1986 fuel-injected 5. Re: Hesitation and slight popping during acceleration? Why? i have the same problem. My GF's 99' Mustang is getting a Random Misfire that only comes up at start up. I noticed on the freeway I my truck was a little rough from the engine and I got off and it was idling rough too. Ford's lightweight six-cylinder engine debuted in the '60 Falcon and Mercury Comet as the 144ci six. 2015 Mustang GT W/PP Cylinder 8 misfire Hey folks, I'm looking for some guidance. Over 2 amps at the plug (10 times more than OEM and 4 times more than other aftermarket ignition systems). Random misfire off idle and under light load. the main reason i bought this was for diagnostic purposes. Mods as follows, codes stored 552 553 565 trickflow street heat iintake msd pro billet ddistributor bbk cold air iintake accel super coil ford 9mm wires. • Eliminates engine misfire under boost or high load. It's the worst when going up a hill, I have to make it shift out of OD and hit about 3k rpms so it doesn't misfire. About 200 miles into the trip, the CEL comes back on. SYMPTOM SUMMARY The engine misses or idles poorly. You may have to register before you can post: click the register link above to proceed. 6 so dont see an issue with fuel. Whats up fellas, I have an 00 Denali, original owner currently 174k on the odometer. DIAGNOSE - ENGINE MISSES OR IDLES POORLY. Re: HEAVY misfire under load/acceleration. A few months ago i replaced the heads and the car was running great up until a few weeks ago. The SES light also came on. Craig's Ford 289 Motor misfiring ! Adjusting timing and mixture on your classic carb 66 Mustang 1966 Mustang Coupe - Day 54 How to diagnose a misfire that isn't ignition related. 8L Compatible with C1312 DG485 FD498: Coil Packs - Amazon. A problem with the plugs, wires or coil pack will produce a misfire under load and store a diagnostic trouble code in the control module's memory. A typical ford engine code po301 code is set when there is a misfire in cylinder 1. (Not bad for a 22 year old car with no known mods to the engine. I have been having this problem for a couple weeks now. 8 and did a lot of work to it over the last 5 days. If you have a friend that has a Ford IDS or a scope that can look at the ignition firing you can pinpoint it. i had the check engine light come on in my 6. It won’t do it at idle, during acceleration, or while cruising. 2005 Ford F150 King Ranch Edition 5. It may be a big clue into what the problem is. DIAGNOSING FORD MISFIRES BY BOB PATTENGALE DIAGNOSING BY BOB PATTENGALE. I have done the plugs, wires, cap, coil, rotor and the fuel filter and I replaced an 02 that was going bad as well with no help, I also tested the fuel reg and it is good. It's strong on reliability but not much on power. There was a break in one of the ignition wires that only short circuited under load. What else could be the problem?. 1997 Ford Mustang SVT Cobra 4. I just bought a '02 Mustang 3. For instance, 00-03 should be 40psi at idle and slightly more under load. New injectors two years ago and new fuel filter regularly HAD THREE fuel pumps as many are junk. #2 plug wire caused a misfire, but my Ultragage showed wild spark advance ranges when it misfired. I've been experiencing misfires under load. Suddenly can't accelerate past 2000 RPMS, hot or cold under load. ecoboost mustang cylinder 2 misfire,. 0L is that in a SOHC engine there is a camshaft sitting on the top of each cylinder head with the valves running directly off the camshaft. Fuel flow is small at an idle and. Need help with intermittent engine sputter and loss of power My 1986 fuel-injected 5. Crank and cam are lined up. 0l mustang misfire. 96 misfire under load, help please I have a 96 7. As you have said that the car runs better on a particular make of spark plug and have seen improvement on changing leads I am betting this is a poor spark issue and the spark is being snuffed out under load. These items are covered under Ignition Troubleshooting. 2L with 99,000 miles. The following ignition system components could cause a misfire when they fail: BAD COP (Coil-on-Plug) Ignition Coil. So, I should let the dizzy control everything under high load and let the computer do advance when under low load conditions. The pressure your car should have at idle and under load depends on the year. Mustang Misfires Second Chance Coupe 1990 Mustang LX. hey everyone- im new to the site but really need some advice. Scan data showed a misfire DTC and an active misfire on the engine. 0L V6 Ford) (at: autotecnico-online. now it seems to only misfire when i put it under a heavy load and my check engine light is on and it started flashing today when i was driving it. I just bought a '02 Mustang 3. Q: I have an 88 mustang with a new cam, springs, coil, distributer, fuel pump, spark plugs, wires, timing chain and I'm having a sputter problem if I go over 3500 rpm and if I keep pushing it it will backfire. The basic symptom of a misfire is a light to severe rough idle that's felt when the engine is idling and a light to severe engine miss (hesitation) when the engine is under load (for example: your Ford vehicle moving from a stop). Have you ever wondered why your 3. i did find where you load the pids into the table display but from what i see i need the other interface to do so. This Sable came into the shop with a customer complaint of a misfire, hesitation at idle and under a load (going up a hill). When a misfire occurs, you can feel it like a light or massive jerk coming from the engine. 86,000 miles and a great runner (till now). (1) 2" Grade 8 3/8" coarse thread Bolt (29 cents)(1) Grade 8 Nut for above (2) Washers for above (1) 10" length of 10 or 8 gauge stranded-core electrical wire. A problem with the plugs, wires or coil pack will produce a misfire under load and store a diagnostic trouble code in the control module's memory. Hi all, I have looked at various current and previous threads on misfire, but most seem to relate to warm or running, I only get mine on starting from cold and then rarely. When I start up a hill or just push the pedal to the floor it has an occasional miss. 2003 Ford Mustang Technical Service Bulletins. Also, it may run fine most of the time but suddenly misfire or cut out for no apparent reason. A problem with the plugs, wires or coil pack will produce a misfire under load and store a diagnostic trouble code in the control module’s memory. Random misfire off idle and under light load. Misfire at low RPM and when engine is under load. Compression misfires are most often caused by leaking intake or exhaust valves, mechanical valvetrain failure or incorrectly timed camshafts. A fuel filter restriction is not the likely cause of an engine running rough when idling. My 04 gt has been misfiring under load and at cruise above 2500 rpm. misfire under load when hard accelerating after 40 - 2006 Ford Mustang GT Close. Unlike fuel misfire symptoms, mechanical misfire symptoms will not go away with higher engine speeds, and often get worse. I have a 1973 Mach 1 Mustang 302 auto. 2001 Ford f 150 4. I have a 2000 Mustang GT, 5spd with 48k miles and it started to develop a stutter/shutter/chugging while driving today. Also my car seems to pop a lot more than before the motor rebuild like all the time. Makes sense! Thanks! _____ Fordfanboi 1966 Ford Mustang hard/soft top Coupe-vertible. The air/fuel ratio can also be affected by changes in altitude. It's not LSPI. There is a TSB out about that model expedition. 0 ho mustang Hesitates under load only when hot? 2L zetec mondeo 1995 misfire under load? they are not under load because the springs support the weight of the vehicle. The vacuum leak sources include the PCV and its hose to the intake and the EVAP hose from the firewall EVAP solenoid to the intake. Locate A Dealer. I have been having this problem for a couple weeks now. Originally, I diagnosed and repaired a P1136 code by replacing the bank 2 camshaf sensor. engine misfire with diagnostic trouble tsb 06-5-13 code (dtc) p0301, p0302, p0303, p0304, p0305, p0306, p0307, p0308, and p0316. The car was idling rough but drove fine with the exception of a hicup here and there while accelerating. after doing so i have noticed that it has a miss only when when under a load such has climbing a hill or in over drive runs smooth until these times! No CEL what so ever! Any help would be greatly appreciated! Hopefully someone else has encountered this problem and found a solution. :thinking: I took it in to scan it at school and it had no thrown codes or codes in it's history. A look under the hood revealed plug cables in sad shape, a sure. Most “300” codes involve the firing of the cylinders. Start by checking for intake leaks and if no leaks are found the next step is to replace the spark plugs on cylinder 3. I cleaned the MAF, checked all vacuum lines and cleaned the air intake body. Average repair cost is $500 at 60,150 miles. I've tried replacing the fuel filter several times and currently have the gas tank off thinking that it might have rust or gunk that is fouling the lines. If the engine speed fluctuates enough to cause the Crankshaft Position sensor signal to vary, the Engine Control Module can determine that a misfire is occurring. You will have a slightly rough idle but the vehicle will perform normally under acceleration, up until when the injector becomes completely clogged and creates a cylinder misfire all of the time. Today's OBD II systems are so sensitive to misfires that they will set a misfire code if they detect as few as five misfires in 200 engine revolutions! Unfortunately, this high level of sensitivity can sometimes generate false misfire readings under certain operating conditions. I thought the MAF would to out in a flat line if flow was exceeded but it seems not?. It doesn't matter if its a cold start or a warm start, its just random. 1-3-4-2 clockwise is firing order. I won't mention your choice of plugs but go get a set of the correct autolite or motorcraft. Craig's Ford 289 Motor misfiring ! Adjusting timing and mixture on your classic carb 66 Mustang 1966 Mustang Coupe - Day 54 How to diagnose a misfire that isn't ignition related. And still a rough idle when on the gas truck runs like a champ!!!! When under load and slight throttle on small incline can feel the truck surge/Skip Snap on Verus has no data and no codes in system. Spark plug fouling is a common cause of engine misfire. Decided I would Easter egg the COPs by buying one new one and replacing till the CEL went away. Mods as follows, codes stored 552 553 565 trickflow street heat iintake msd pro billet ddistributor bbk cold air iintake accel super coil ford 9mm wires. Besides the cylinder misfire, you're going to notice one or more of the following symptoms: Rough idle. I replaced the spark plugs & cleaned the cap & rotor with a small wire wheel attached to a dremel, but i still have a mis-fire under load. When my VQ35DE isn't under load, it misfires. No engine fires every cylinder 100% of the time. So any time it hits OD and the load is high, it'll miss HARD. If the engine speed fluctuates enough to cause the Crankshaft Position sensor signal to vary, the Engine Control Module can determine that a misfire is occurring. Shudder / Shaking Misfire Under Load - not spark plugs. I have a 1997 ES 2. Mustang Misfires Second Chance Coupe 1990 Mustang LX. Mustang Girl Monday: Jennifer Awad (Crismale) and her 1990 Mustang GT. then check the compesion you need. The IDS has a power balance feature that compares each cylinder. check engine light started flashing. Start with replacing plugs and gapping down if you have not already. We'll walk you through how to properly diagnose and fix a flashing check engine light. Suddenly can't accelerate past 2000 RPMS, hot or cold under load. [Solved] Misfire under light load. First make sure you determine the location of #2 cylinder. Need help with intermittent engine sputter and loss of power My 1986 fuel-injected 5. Also, under load at moderate to high rpm the speed of the distributor keeps the reverse torsion of the shaft to a minimum. :thinking: I took it in to scan it at school and it had no thrown codes or codes in it's history. I had a wicked misfire that only happened under load. But under load, the short circuit became the path of least resistance. 054) replaced fuel pump (injectors and rails are in excellent shape but fuel pres was low side) the car spent 2 weeks in the shop the best results came after clearing the computers flash memory then rebooting ( not just unhooking the bat ) fellas at the shop are as stumped ad i am. Sometimes I can floor it in 5th at say 45 and it just pulls smooth like normal, other times it has a misfire. I have a misfire code for cylinder 5 (P0305) and it keeps going in out of loop. Miss occurs at 40 to 50 miles an hour under part throttle while the trans is still in overdrive. It runs better but still. My 2006 mustang gt misfires under load in higher rpms. Is your car running rough, engine shakes, and the catalytic converter seems too hot? Your check engine light may also be on with a misfire code. From spark plug changes to major service, your 2000 Ford Mustang will perform at its best when you maintain and repair it with our replacement ignition parts. 3 z71, 148k miles, and brand new tranny (condition existed both before and after tranny rebuild) on acceleration in 1st or second gear (dont usually get 3rd gear to 3000 rpm) when i get to around 3000 rpm the engine stumbles real bad. Diagnosing Ford Misfires. Forced induction engines may need gaps as small at 0. 97 crown vic misfire/backfire 1 Answer. I thought the MAF would to out in a flat line if flow was exceeded but it seems not?. Check the condition of your plug wires and coil towers (the contact inside the coil tower should be bright and shiny). I had a wicked misfire that only happened under load. I had the same type of problem on my 2004 Ford Mustang with misfires under slight load; changing out to iridiums did the trick. A weak coil shows up very clearly. Here are some: Stalls at idle, stalls when I put the clutch in, stalls when I turn a corner, misfires, surges, no power, cuts out, no power at top revs, runs rough, etc. You will have a slightly rough idle but the vehicle will perform normally under acceleration, up until when the injector becomes completely clogged and creates a cylinder misfire all of the time. If I accelerate, or run at a higher RPM, it goes away. That is why your mechanic cannot communicate or get codes for the check engine light. At the dyno shop another sn95 Mustang owner was asking me about my distributor. Will back fire sometimes. Also, it may run fine most of the time but suddenly misfire or cut out for no apparent reason. Learn all about your Ford vehicle on the Official Ford Owner Site! Schedule Service. Hi all, I have looked at various current and previous threads on misfire, but most seem to relate to warm or running, I only get mine on starting from cold and then rarely. Our main offerings include: MegaSquirt Plug-N-Play Engine Management System Kit, including several new vehicles, our MegaSquirt-I system, MegaSquirt-II, and MegaSquirt-III Assembled and unassembled versions, both with black cases. I got one of those in a few weeks ago. My 04 gt has been misfiring under load and at cruise above 2500 rpm. I have changed the spark plugs and wires but it still seems to misfire at idle under load. com (or Ford 4L or Ford 4. It's hard to log bc it's not consistent. The light came on and it was a cylinder misfire. The second solution to misfire is to increase the electrical potential (voltage) of the ignition system. Ford Distributors & Ignition Systems: Few things about an engine build seem more mysterious and magical than the ignition system. Take a timing light under the hood to make sure the timing belt or chain has not slipped or jumped. P0300 code coming up! 1993 Mustang LX If the engine starts and idles ok from a cold start,then backfires under. I thought the MAF would to out in a flat line if flow was exceeded but it seems not?. I replaced plugs with OEM and OEM WIRES new distributor and cap and rotor. It may well be that these events are the hesitation & stumble problems described in this article. then the code 306 came back. The MAP sensor (manifold absolute pressure) can cause a lean misfire especially under load because all engine calculations are based off of that sensor and it measures air density, they can fail and read that you're at say for example 30,000 feet when you're at sea level, which air is thinner so you need less fuel - causing the engine to run lean. Use our extensive table below should help point you in the right direction to help get you closer to getting your pony back on the road!. Check the wire and plug for corrosion. Ran great for several weeks. I would "think" the misfire. Yes the timing chain and and bearings wear out and yes they do affect timing, but stretched timing chain retards the timing, not advance it. now it seems to only misfire when i put it under a heavy load and my check engine light is on and it started flashing today when i was driving it. A trained transmission-service technician can also test for torque converter lockup using a specific vehicle scan tool. The carb I am using is a NOS Holley 9834-1 Here is what happens: Car starts fine hot or cold. 6 small V-8 with coil on plug ignition. If a camshaft lobe is halfway worn down, it will show up only when the engine is running and under load. Big surprise. A typical ford engine code po301 code is set when there is a misfire in cylinder 1. I can hear it popping well from under the car, but not really from above the engine. I have a 1997 Ford Crown Victoria that misfires and backfires under any kind of load it takes it forever to get up to speed and it's very lurchy. Under a load probably most prevalent with the trailer at about 1500 rpm or so until about 2000 rpm or so the truck bucks pretty bad like it has a misfire. Q: I have an 88 mustang with a new cam, springs, coil, distributer, fuel pump, spark plugs, wires, timing chain and I'm having a sputter problem if I go over 3500 rpm and if I keep pushing it it will backfire. 8 and did a lot of work to it over the last 5 days. Most usually around 45 to 50 mph 1400 rpm. Please try again later. If the engine speed fluctuates enough to cause the Crankshaft Position sensor signal to vary, the Engine Control Module can determine that a misfire is occurring. Lack of power when you accelerate your Ford Mustang on the road. I have changed the spark plugs and wires but it still seems to misfire at idle under load. that took the O2 sensor code, and the 306 until I droved it for 10 min. Compression Misfires. 8/Auto - Rough Cold Start - Misfire under light load - No CEL I have a 2002 mustang V6 3. Of course, a misfire while accelerating meant the Toyota V6 got even slower. Occasionally under load I get a crazy misfire and no power. If you haven't changed the spark plugs in a while the gap will get so big that the ignition spark will look for an easier place. It wasn't apparent once it picked up the speed. And with nine unique trims, you’ve got options, from the fun and energetic GT Convertible to the 2020 Shelby GT500 ®, host to the most power-dense supercharged V8 production engine in the world. When a coil failure occurs, the coil's voltage output drops, and the engine may not start or may misfire badly when under load. It's hard to log bc it's not consistent. Full throttle or above 2k seems fine. 6 small V-8 with coil on plug ignition. Random misfire off idle and under light load. 0 V8 with dual fuel tanks has been running roung/sputtering/and lacking any power to go above 20mph. Can be sometimes accompanied by p0300 misfire code and p0301-p0306 codes indicating an individual cylinder. Your engine is equipped with an inadequate COP ignition, "coil on plug" manufactured by DENSO not GM. The control module interrupts current flow through the primary windings of the coil to create the high voltage needed to fire the spark plugs. A look under the hood revealed plug cables in sad shape, a sure. My 2015 GT 5. 5: When driving it normally under light load and while using proper gears and rpm to travel up hills it drives fine. Here are some: Stalls at idle, stalls when I put the clutch in, stalls when I turn a corner, misfires, surges, no power, cuts out, no power at top revs, runs rough, etc. 0 under a load when i passed some one but it only flashed for a few about 10 seconds. It seems like an ignition problem, like its on and off running on 7 cylinders only under load, and missing. Fuel pressure is set to 42 vacuum off, stock mustang pump, boost is. 2002 mustang gt, 80k miles, misfiring about three months ago, replaced coils and spark plugs, fixed problem until now. Most "300" codes involve the firing of the cylinders. Colt's Manufacturing Company - firearms, handguns, pistols, rifles, revolvers. Mustang Misfires Second Chance Coupe 1990 Mustang LX. If the frequency of misfire is high the Powertrain Control Module (PCM) may place the engine in "Limp-In" mode. hello everyone, i just bought a 93 bronco with the gas friendly 5. In such cases, the car feels like it has lost power, you notice poor fuel economy, poor performance, and poor throttle response. And if the spark plug is causing a misfire, you're gonna' have a corresponding misfire trouble code lighting up the check engine light on your Ford Mustang's instrument cluster. Refer to Fuel filler cap under the Fuel Information section in the Maintenance and Specifications chapter. That is what sets a no activity code as the 02 sensor will read a lean condition due to the misfire. Someone's already mentioned GM cars switched over to SD under boost conditions?. 2008 Tundra 5. 0 V6 misfire Not to scare you but I chased this same problem around for a while, changed plugs and wires and coil pack and kept getting either cylinder 4 or 6 misfire code. In late 1995 and up, the connector under the dash was used. If a valve spring has broken or a cam lobe has worn down, it will cause the engine to misfire and run rough due to the loss of compression. I cleaned the MAF, checked all vacuum lines and cleaned the air intake body. Re: 1993 Mustang - won't stay running, help i have no clue as i would like to know also cause i had a car that did that but it was a honda. Average repair cost is $3,900 at 79,750 miles. 302 Ford, Cyl. Will back fire sometimes. i have the standard 499. The only issues I've ever had was a bad wiper switch and brake light switch that would turn the brake lights on when it got cold over night. This indicated that the ground electrodes were hotter than the centre electrodes under light loads and vice versa at WOT. Here are some: Stalls at idle, stalls when I put the clutch in, stalls when I turn a corner, misfires, surges, no power, cuts out, no power at top revs, runs rough, etc. when the car is cold and I put the engine under load, it will hesitate and the exhaust will pop. Ok here goes. I found it by revving the engine and listening to the engine bay. I noticed on the freeway I my truck was a little rough from the engine and I got off and it was idling rough too. Start with replacing plugs and gapping down if you have not already. 0 V6 OHV equipped Ranger for 10 years now and am very surprised at how little info there is on the net for this engine/vehicle combination. Besides the cylinder misfire, you're going to notice one or more of the following symptoms: Rough idle. I get to my destination where Im doing a bunch of work (headers, exhaust, tune, short throw shifter, transmission fluid, thermostat) and drive back. My 2006 mustang gt misfires under load in higher rpms. now it seems to only misfire when i put it under a heavy load and my check engine light is on and it started flashing today when i was driving it. You will have a slightly rough idle but the vehicle will perform normally under acceleration, up until when the injector becomes completely clogged and creates a cylinder misfire all of the time. Your path: TSB Home >> 2003 >> 2003 Ford >> 2003 Ford Mustang The following TSB(s) may apply to your 2003 Ford Mustang. Car was running fine - Ford 1966 Mustang question. Auto Body Problems. 2 V6 with P00303 and P00306 misfire codes, 178,000 miles, well maintained.