The great misfire mystery
07-04-2007, 10:47 PM
#76
Registered User
Join Date: Jul 2007
Location: ontario.canada
Posts: 5
just picked up a 97 rs 3.8l with a stumble.Buddy of mine(chrysler tech) has an obd2) (engine light was on and it had a bit of a stumble at or below 2000rpm going into a hill but not pushing it enough to drop a gear,peddle into it and it was o.k. buddy came over the next eve, went for a drive to determine hot or cold ran it hard from a stand still and a serious misfire started all the way up through (was quite impressed with the accelleration for a 6) got the code # 2 cyl misfire...started checking for bad contact (corrosion on plug wires and coil packs and #1 boot seemed loose and i did not like how two was routed)pulled plug on #2 and it was new (so is the 2-5 coil pack)that was it for the night. He decided to bring home a realtime analizer from work (quite a unit) plugged in the car info run it out on the road and the car never got any serious misfiring (it showed the odd mis on various cyl, but never consistant, nor could you feel it and no engine light! will replace wires anyway but i'm quite impressed with this car ,exceding my expectations....this is supposed to be wifeys toy but i'll have to see what kind of giddyup parts i can get for this thing..... it does start hard on first attrmpt but second time bang it's going (fuel sys. not holding pressure?)
09-06-2007, 11:14 AM
#77
Registered User
Join Date: Sep 2007
Location: wisconsin
Posts: 1
????
so has anybody else gone threw and replaced plugs and wires and taken it out and as soon as the mottor warmed up the miss fire came back??? also im only haveing the problem on cylinder 3... and it only happens in the 1000 to 3250 rpm range...
Last edited by m_carlson; 09-06-2007 at 11:15 AM. Reason: needed to add more
09-07-2007, 01:14 AM
#78
Registered User
Join Date: Sep 2000
Location: Houston TX
Posts: 315
09-10-2007, 01:02 PM
#79
Registered User
Join Date: Sep 2000
Location: Houston TX
Posts: 315
Ok, after three weeks of this, heres what I've found. I replaced the 3-6 coil (had misfires on both cylinders), the ICM, plug wires( 3 and 6 feel apart in my hands), and 3-6 plugs.
This is a 98 3.8 BTW
There was no change after the coil and module.....moderate misfiring and stumbling under load in every gear but first. After I replaced the plug wires the problem actually GOT WORSE! It then started missing in first as well under any load. Scan tool says its #4 now. After spending all day friday and saturday at my uncles shop trying to figure out what was wrong (we did a fuel system treatment, injector cleaning, throttle body cleaning, vacumme test, emissions, the whole nine yards) I still had nothing.
Finally on a whim I rerouted the #4 plug wire around the back of the engine away from 2 and 6 and removed the heat shield. As best as we can figure, it was picking up interference from the other wires or shorting out on the heat shield. Keep in mind that these are cheap autozone plug wires with no insulation other than the factory wire wrap.
My car is now a case study for my uncles ASE classes he teaches...so maybe the problem will get a little more exposure!
This is a 98 3.8 BTW
There was no change after the coil and module.....moderate misfiring and stumbling under load in every gear but first. After I replaced the plug wires the problem actually GOT WORSE! It then started missing in first as well under any load. Scan tool says its #4 now. After spending all day friday and saturday at my uncles shop trying to figure out what was wrong (we did a fuel system treatment, injector cleaning, throttle body cleaning, vacumme test, emissions, the whole nine yards) I still had nothing.
Finally on a whim I rerouted the #4 plug wire around the back of the engine away from 2 and 6 and removed the heat shield. As best as we can figure, it was picking up interference from the other wires or shorting out on the heat shield. Keep in mind that these are cheap autozone plug wires with no insulation other than the factory wire wrap.
My car is now a case study for my uncles ASE classes he teaches...so maybe the problem will get a little more exposure!
09-10-2007, 09:53 PM
#80
Registered User
Join Date: Sep 2007
Location: Texas
Posts: 18
Picture
I went to napa auto parts to get the sheathing for my plug wires they had no idea what i was talking about so i tried to look to see if i could find it no luck maybe some one could give me a dicripition of this item or a picture upload. thanks a million great post and site.
11-15-2007, 02:57 AM
#82
Registered User
Join Date: Apr 2006
Location: Oshkosh, Wi
Posts: 167
So are the plugs on the underside of the engine? Can the wires be replaced without taking anything apart? Am i going to have to go at this from underneath the car?
Do boot covers actually help on a 99?
I've got 93,000 on the car and it ran great up until 2 weeks ago. Are the later model v6's cooler than earlier models? Will i most likely get another 90,000 out of new plugs and wires?
12-17-2007, 03:28 PM
#83
Registered User
Join Date: Apr 2007
Location: Brownsboro, Texas
Posts: 2
96 #5 misfire
I have had the same problems as everyone else seems to have.
So far, I have performed pretty much everything anyone else has tried on this thread. Originally, the car had a #5 misfire and EGR Pintle position codes that set regularly. I would reset them with my scanner and they would return regularly, but not instantly.
After several attempts to isolate the problem/solution, here is the list of what I have done so far:
New EGR - no change at all. Both codes still set as before.
New #5 fuel injector - no change whatsoever at all
New coil pack - some better but still would misfire and set #5 code as well as the EGR code
New plug wires (equivalent to factory, with shields, and new #5 plug) - it did get better but would occasionally set the #5 misfire code.
New coil packs so that all three are new now - The misfire problem went away.
So far, after over 2000 miles the misfire code has not returned. When I put the new wires on, I did route them so that they were not any closer to the exhaust manifolds than they had to be.
It runs good.
BUT -
Now, I still have an intermitent EGR Pintle postion error code, and I have checked everything I can find, read, or think to check. I have checked the orifices and tubes and they are clear of carbon. The EGR plug is nice and tight and no bent pins. I even removed the computer and checked the connections to it.
Still, the EGR pintle position code will set fairly often. It seems to set mostly when the car is coming to a stop and the engine speed drops quickly. It has never set when driving at highway speeds.
Anyway, for the misfire, I did all the above and it went away. My thoughts now are similar to several of the earlier posts to this thread that the plug/wires were going bad and weakened the coil packs. If it happens to me again, I will change wires and coil packs without going thru all this again.
If you have any thoughts on this EGR error, just post me an idea.
Thanks,
Buddy
So far, I have performed pretty much everything anyone else has tried on this thread. Originally, the car had a #5 misfire and EGR Pintle position codes that set regularly. I would reset them with my scanner and they would return regularly, but not instantly.
After several attempts to isolate the problem/solution, here is the list of what I have done so far:
New EGR - no change at all. Both codes still set as before.
New #5 fuel injector - no change whatsoever at all
New coil pack - some better but still would misfire and set #5 code as well as the EGR code
New plug wires (equivalent to factory, with shields, and new #5 plug) - it did get better but would occasionally set the #5 misfire code.
New coil packs so that all three are new now - The misfire problem went away.
So far, after over 2000 miles the misfire code has not returned. When I put the new wires on, I did route them so that they were not any closer to the exhaust manifolds than they had to be.
It runs good.
BUT -
Now, I still have an intermitent EGR Pintle postion error code, and I have checked everything I can find, read, or think to check. I have checked the orifices and tubes and they are clear of carbon. The EGR plug is nice and tight and no bent pins. I even removed the computer and checked the connections to it.
Still, the EGR pintle position code will set fairly often. It seems to set mostly when the car is coming to a stop and the engine speed drops quickly. It has never set when driving at highway speeds.
Anyway, for the misfire, I did all the above and it went away. My thoughts now are similar to several of the earlier posts to this thread that the plug/wires were going bad and weakened the coil packs. If it happens to me again, I will change wires and coil packs without going thru all this again.
If you have any thoughts on this EGR error, just post me an idea.
Thanks,
Buddy
05-27-2008, 06:10 PM
#84
Registered User
Join Date: Aug 2006
Location: Mount Laurel, New Jersey
Posts: 16
Sorry to revive this thread, however I think I have this issue with my 2001 v6. I only notice a light miss when the car is sitting at idle. Once I hit the gas, it goes away. It is only every so often as well, ie weather change between hot/cold and damp/dry. I had a tune up 2 years ago where they replaced the plugs,cables and coils. I was looking at the cables and some of them have black marks on them....
also, Im thinking about putting the boots and heat protectors on the cables. Where do you get those? The auto parts stores around here don't seem to know what I am talking about.
Help would be awesome!
Fred
also, Im thinking about putting the boots and heat protectors on the cables. Where do you get those? The auto parts stores around here don't seem to know what I am talking about.
Help would be awesome!
Fred
06-30-2008, 03:11 PM
#85
Registered User
Join Date: Jun 2008
Posts: 7
I hate to add more to the crazy #4 misfire but here are my issues and any help would be greatly appriciated.
98 camaro I have the issue where I can give it about 1/4 peddle with no problem through the gears except taking off in 1st (will buck violently. If I demand more than a quarter gas thats when I start to sputter and buck and throw a p0304 (#4). I won't get it though if it's real easy exceleration. So I changed the fuel filter, plugs, wires, coils, ignition module, and #4 injector. Did not improve the issue one bit. O2 sensor maybe? I don't know anymore. Very appravating. Should I change the wires and plugs again? HELP!
98 camaro I have the issue where I can give it about 1/4 peddle with no problem through the gears except taking off in 1st (will buck violently. If I demand more than a quarter gas thats when I start to sputter and buck and throw a p0304 (#4). I won't get it though if it's real easy exceleration. So I changed the fuel filter, plugs, wires, coils, ignition module, and #4 injector. Did not improve the issue one bit. O2 sensor maybe? I don't know anymore. Very appravating. Should I change the wires and plugs again? HELP!
07-09-2008, 08:54 PM
#86
Registered User
Join Date: Apr 2007
Location: Brownsboro, Texas
Posts: 2
Fred,
I found the plug wire insulators at AutoZone. Online, you can find them at a variety of places such as JEGS, etc.
Sorry for such a delay in response, but I haven't logged in for awhile.
Buddy
I found the plug wire insulators at AutoZone. Online, you can find them at a variety of places such as JEGS, etc.
Sorry for such a delay in response, but I haven't logged in for awhile.
Buddy
10-24-2008, 04:19 PM
#89
Registered User
Join Date: Jan 2008
Posts: 48
add me to this problem ok heres wat i got and have done.
6 codes
(2)cylinder 1 misfire
(2)egr emssion
transmission slip
o2 bank 1 sensor 2
ok
now ive replaced the plug and wire on the cylinder 1 no luck same thing
im going to try putting a new coil soon and see if that helps i found a set at my pick_n_pull for 40$ they all look aftermarket is it worth getting?
egr looked great no carbon at all so i took the tb off and found the sensor on the side of the intake was pluged up with alot of oil/grease cleaned that and now will have to clear codes and c if it comes back. there is alot of black inside the intake is this ok?
6 codes
(2)cylinder 1 misfire
(2)egr emssion
transmission slip
o2 bank 1 sensor 2
ok
now ive replaced the plug and wire on the cylinder 1 no luck same thing
im going to try putting a new coil soon and see if that helps i found a set at my pick_n_pull for 40$ they all look aftermarket is it worth getting?
egr looked great no carbon at all so i took the tb off and found the sensor on the side of the intake was pluged up with alot of oil/grease cleaned that and now will have to clear codes and c if it comes back. there is alot of black inside the intake is this ok?
12-03-2008, 03:21 PM
#90
Registered User
Join Date: Feb 2001
Location: Casselberry,FL
Posts: 285
Just wondering if anyone has tried replacing their harmonic balancer for the stumbling or misfire problem. I have another type of car that was stumbling and it turned out to be the harmonic balancer but the condition was similar to the one described. Some of you have tried plugs, wires etc and still have the issue so I was wondering if this may be the problem or at least part of the problem, let me know if you have tried that. Thanks!