Jump to content

Loss of power/cylinders after engine warms up


Myotis1134

Recommended Posts

Hey people, I have a new problem that I need opinions on.

 

Four days ago one of my transmission coolant lines came uncoupled at the metal/rubber crimp, blowing approximately six liters of fluid across the parking lot of my workplace. I didn't get in far enough to identify the correct hose, assumed it was a leak on the inlet line, and replaced it. Dumped in more fluid to check, and blew yet more fluid around the engine bay (and on the ground). Found out that what I thought was the inlet line was actually the return line.

 

Anyways, the car ran like a champ after that, but smelled pretty bad for about two days from all the tranny fluid that splashed around.

 

Then on day four, as I'm pulling into work I suddenly loose power. Feels like I lost a couple of cylinders, and rough idle- the tach needle is literally vibrating. No codes get thrown.

 

When I start it up after work it runs like a champ, until the engine gets warm, and then I loose power. The weird thing is that every now and then I get full power back (usually on acceleration), but never for more than a few seconds.

 

I've been looking over the posts and seen everything from ICM to coil pack to crank sensor to ox sensor to fuel pump. I've looked over and tested my plug wires, and all the connection points on the coil packs look clean.

 

When I get paid in a couple days I'm getting a new ICM, coil packs and a crank sensor. These seem to be the main culprits in this kind of problem, and I think it makes sense that these parts would go. This is what I'm seeking opinions on: is it possible that all of the tranny fluid that was sprayed on this area could seep onto the coils/ICM/Crank sensor, heat up and fry them?

Link to comment
Share on other sites

I'd put my money on either coil packs or ICM. I don't think that the ATF sprayed all over would cause your issue; I suspect that the timing is likely coincidence.

 

Do you have access to a timing light?

Link to comment
Share on other sites

When you get the timing light, I've got a creative way to check for misfiring at speed, but you do need a helper for it. Hook up the timing light, and tie the trigger down so that the light always pulses. Rig up the light so that you can get the wires around the hood somehow, and secure it someplace a passenger can see it while driving (but out of the vision of the driver; you don't want a strobe light in your eyes while driving).

 

Go out for a drive, and get the car to act up. If the passenger sees the light cut out at the same time the car acts up, you've found a problem with the spark on that cylinder. If the light continues without hesitation, there is no spark issue on that cylinder. Repeat the process for all cylinders, and note which ones (if any) act up.

 

If you isolate the problem to one coil pack, then switch that coil pack with one of the others and see if the problem follows the coil pack. If it does follow the pack, then the pack is dead and needs to be replaced. If the problem does not follow the coil pack, or you see it randomly on all cylinders, I'd say the ICM needs to be replaced.

 

Of course, this all does assume that the issue is spark, although I think it is.

Link to comment
Share on other sites

When you get the timing light, I've got a creative way to check for misfiring at speed, but you do need a helper for it. Hook up the timing light, and tie the trigger down so that the light always pulses. Rig up the light so that you can get the wires around the hood somehow, and secure it someplace a passenger can see it while driving (but out of the vision of the driver; you don't want a strobe light in your eyes while driving).

 

Go out for a drive, and get the car to act up. If the passenger sees the light cut out at the same time the car acts up, you've found a problem with the spark on that cylinder. If the light continues without hesitation, there is no spark issue on that cylinder. Repeat the process for all cylinders, and note which ones (if any) act up.

 

If you isolate the problem to one coil pack, then switch that coil pack with one of the others and see if the problem follows the coil pack. If it does follow the pack, then the pack is dead and needs to be replaced. If the problem does not follow the coil pack, or you see it randomly on all cylinders, I'd say the ICM needs to be replaced.

 

Of course, this all does assume that the issue is spark, although I think it is.

 

duct tape on the windshield will do wonders for your street cred :lol:

Link to comment
Share on other sites

duct tape on the windshield will do wonders for your street cred :lol:

 

Fo shizzle yo! :lol:

 

But seriously, a mechanic who was helping me troubleshoot told me about this trick. It gets the job done!

Link to comment
Share on other sites

Huh, that's a damn good trick. Guess I'll be getting a timing light.

 

Ok, here's something I've been curious about- On jbodyperformance.com (where they have the sweetest 3.1 headers), I was looking at the gallery of customer cars that they have pimped out, and saw on one that they moved the ICM to the inside of the driver-side fenderwall. Is that something worth considering? I'll admit that I'm not sure that there is room over there without some creative rearranging, but it would keep everything clean and accessible.

Link to comment
Share on other sites

thats a hell of a lot better location than right next to the exhaust, as per the factory.... you might have to lengthen the plug going to the ICM, and get longer plug wires, but nothing tough to do...

Link to comment
Share on other sites

Do yourself a favor and get a used ICM/coil packs. It's much cheaper and the new store ICMs are really junk aka "Made in China". My new "autozone" one only lasted two years, and I had to do the whole process over again with a used part. The used part also felt a lot more solid with a better grade of plastic compared to the new part.

 

So far I've noticed that with a lot of electronic parts available for our cars.

Link to comment
Share on other sites

...they moved the ICM to the inside of the driver-side fenderwall. Is that something worth considering?

 

I dunno about the fenderwell, but you could probably do something like the later LQ1s or 3100s and mount it on top, towards the back of the motor. As it has been said, the factory location is definitely less than ideal.

 

Do yourself a favor and get a used ICM/coil packs. It's much cheaper and the new store ICMs are really junk

 

Very good advice, unless you buy Delco parts. Of course there goes cheap right out the door! :lol:

 

 

Link to comment
Share on other sites

Kind of slim pickings for junkyard parts here in AK. I needed the parts asap, and the guys at CSK were all morons, so I went NAPA for the ICM and Coils. If they get fucked up at least I have a warranty on them. Just got done pulling the old coils and ICM off the car. Think this might have had something to do with the problem?

Link to comment
Share on other sites

Yeah. Big time.

 

Put everything back together. Runs like a champ once again. Relocation is going to have to wait for a warmer day.

 

Next project - fix steering that pulls to the left.

 

Thanks for the help people.

Link to comment
Share on other sites

Yeah. Big time.

 

Put everything back together. Runs like a champ once again. Relocation is going to have to wait for a warmer day.

 

Next project - fix steering that pulls to the left.

 

Thanks for the help people.

 

well thats probably just your alignment out of whack.

 

about $45 around here for a 4-wheel job

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...