2.8 V6 stumbling and missing
06-21-2010, 09:49 AM
#42
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Okay, I finally had a chance to check for sparking tonight.
The car had been sitting for a couple days. When I went out and started it up, it ran fine. I took it for a drive to warm it up. It ran fine for the first minute or two, then slowly began to get worse and worse. After about 7-8 minutes I brought it back to the house, parked it and popped the hood.
Here's a strange thing. I put the parking brake on and put the car in Reverse to put the engine under load and induce the misfire. Initially, it was "stumbling", but I didn't hear any electrical clicking. I also didn't see any obvious sparks under the hood. After letting it run a while longer, it finally started making a clicking noise (still coming from the left side of the engine). I pulled up the plastic cover on the cylinder bank, and sure enough, there was a big fat spark coming out of the spark plug wire every time the engine misfired. It was right at the point that the wire makes a 90 degree turn into the engine block.
Now at least I know one thing to try. It bothers me that I didn't hear the sparking noise during the initial stumbling. Could it be that there is another factor at play? I guess all I know to do is replace that plug wire and see what happens. Don't even want to know what that's going to cost...
edit: I forgot to mention that I did see some faint, flickering sparks around the ignition coil. Is this normal, or could that be a symptom of a malfunctioning coil?
The car had been sitting for a couple days. When I went out and started it up, it ran fine. I took it for a drive to warm it up. It ran fine for the first minute or two, then slowly began to get worse and worse. After about 7-8 minutes I brought it back to the house, parked it and popped the hood.
Here's a strange thing. I put the parking brake on and put the car in Reverse to put the engine under load and induce the misfire. Initially, it was "stumbling", but I didn't hear any electrical clicking. I also didn't see any obvious sparks under the hood. After letting it run a while longer, it finally started making a clicking noise (still coming from the left side of the engine). I pulled up the plastic cover on the cylinder bank, and sure enough, there was a big fat spark coming out of the spark plug wire every time the engine misfired. It was right at the point that the wire makes a 90 degree turn into the engine block.
Now at least I know one thing to try. It bothers me that I didn't hear the sparking noise during the initial stumbling. Could it be that there is another factor at play? I guess all I know to do is replace that plug wire and see what happens. Don't even want to know what that's going to cost...
edit: I forgot to mention that I did see some faint, flickering sparks around the ignition coil. Is this normal, or could that be a symptom of a malfunctioning coil?
06-24-2010, 04:19 AM
#43
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Hopefully a final update for this thread:
I finally got a chance to install a new set of park plug wires yesterday. I put a little dielectric grease around the bottom of the boot like someone suggested. That seems to have done the trick. I drove it for around 30 minutes yesterday and about 20 minutes to work this morning, and it seems to be back to normal.
I know this isn't going to be the solution to all stumbling/hesitation problems with these engines, but it is certainly one of the things to consider if you're having this problem.
Quick question: are there codes that can only be cleared by a VAGCom? I still have a flashing coolant warning on my cluster display even after I cleared the codes with the universal code reader at AutoZone. The sensor seems to be functioning fine, so I don't think there is actually a problem. If someone can let me know, that'd be great.
I finally got a chance to install a new set of park plug wires yesterday. I put a little dielectric grease around the bottom of the boot like someone suggested. That seems to have done the trick. I drove it for around 30 minutes yesterday and about 20 minutes to work this morning, and it seems to be back to normal.
I know this isn't going to be the solution to all stumbling/hesitation problems with these engines, but it is certainly one of the things to consider if you're having this problem.
Quick question: are there codes that can only be cleared by a VAGCom? I still have a flashing coolant warning on my cluster display even after I cleared the codes with the universal code reader at AutoZone. The sensor seems to be functioning fine, so I don't think there is actually a problem. If someone can let me know, that'd be great.
02-04-2011, 10:06 AM
#44
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Here we go again.
After a fall and winter of running perfectly fine, my car is exhibiting the same symptoms as before: random missing and stumbling under load. It started a month or so ago with just once or twice a day. Now it's doing it regularly. If I delicately apply the throttle, it sometimes allows it to accelerate smoothly. Sometimes it does it not matter how careful I am.
Yesterday, the car finally threw a CEL. I went and had the codes pulled with a generic code reader, and they are as follows:
P1338 - Manufacturer control ignition system or misfire
P0441 - EVAP Emmission control system purge flow fault
It has not yet degraded to the point of stumbling at idle, but I'm sure it's well on its way if I don't figure out what's going on. It seemed to get a lot worse when we had a warm spell a few days ago. Luckily we're back in the 40's.
I just replaced the spark plug wires and plugs 6-7 months ago (as I documented in this thread), so I really can't believe that's the problem. However, that seemed to fix it last summer. This is really disappointing and frustrating. Any new ideas before I go insane?
After a fall and winter of running perfectly fine, my car is exhibiting the same symptoms as before: random missing and stumbling under load. It started a month or so ago with just once or twice a day. Now it's doing it regularly. If I delicately apply the throttle, it sometimes allows it to accelerate smoothly. Sometimes it does it not matter how careful I am.
Yesterday, the car finally threw a CEL. I went and had the codes pulled with a generic code reader, and they are as follows:
P1338 - Manufacturer control ignition system or misfire
P0441 - EVAP Emmission control system purge flow fault
It has not yet degraded to the point of stumbling at idle, but I'm sure it's well on its way if I don't figure out what's going on. It seemed to get a lot worse when we had a warm spell a few days ago. Luckily we're back in the 40's.
I just replaced the spark plug wires and plugs 6-7 months ago (as I documented in this thread), so I really can't believe that's the problem. However, that seemed to fix it last summer. This is really disappointing and frustrating. Any new ideas before I go insane?
02-04-2011, 10:24 AM
#45
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get a vag com so we get the REAL code not the crap autozone scanner...
P1338 - Manufacturer control ignition system or misfire
means nothing, we need to know exactly whats happening which ou need a vag com to do, this is too generic.
P1338 - Manufacturer control ignition system or misfire
means nothing, we need to know exactly whats happening which ou need a vag com to do, this is too generic.
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