Jump to content

What am I missing - GM 2.4L Quad 4


DavidBaustert

Recommended Posts

I'm at my wits end with this thing. P0301 code - misfire cylinder 1

 

Replaced all 4 plugs

Checked Spark in all 4 Cylinders with inline spark tester, all OK

Checked Compression in all 4 Cylinders - 210psi across the board

Swapped cylinder #1 fuel injector with #2, then #3, still P0301

Swapped coils around (Waste Spark ignition), still P0301.

Put a noid light on all 4 injector plugs, all OK

 

I don't know what else to check. Cylinder 1 plug looks like its wet, no carbon from firing, so I believe it's ignition related, but not sure what else to check. Any help is appreciated.

Link to comment
Share on other sites

No idea how to test it, it was just a thought though premature I believe. The more I think about how the ignition on those cars work, the more I realise it would be 2 cylinders misfiring if this was the issue (though I wouldn't rule it out completely yet). Try swapping the spark plug boots around and see if it follows that.
Link to comment
Share on other sites

Did you have really weak spark on that cylinder? I'd bet you do, it really needs checked with a spark tester that'll jump a gap to see how strong it is, because one that simply lights up won't help much. If there is no carbon tracking anywhere, you should be able to take the plastic bullshit apart and swap coils, see if it moves then. Testing the ignition on one of those is a PITA, but a coil sounds like a possiblity the way you described it.
Link to comment
Share on other sites

Did you have really weak spark on that cylinder? I'd bet you do, it really needs checked with a spark tester that'll jump a gap to see how strong it is, because one that simply lights up won't help much. If there is no carbon tracking anywhere, you should be able to take the plastic bullshit apart and swap coils, see if it moves then. Testing the ignition on one of those is a PITA, but a coil sounds like a possibility the way you described it.

 

I've swapped coils already, no change. I'm going to pick up a different spark tester tonight (for gap jump like this one http://www.oreillyauto.com/site/c/detail/LIS0/50850/N0665.oap?ck=Search_N0665_-1_2182&pt=N0665&ppt=C0103) and check it again. I read that the plastic housing can become a conductor and the spark will jump through it arcing to ground. Any experience with this? I pulled the whole coil assembly out and put an old set of plugs in it, grounded them, and cranked with the fuel pump relay unhooked and all plugs were sparking. I don't see any carbon tracking on the boots, but there may be some on the plastic thing, not entirely sure but it looks like a black spider web almost burnt into the plastic?

Link to comment
Share on other sites

I've swapped coils already, no change. I'm going to pick up a different spark tester tonight (for gap jump like this one http://www.oreillyauto.com/site/c/detail/LIS0/50850/N0665.oap?ck=Search_N0665_-1_2182&pt=N0665&ppt=C0103) and check it again. I read that the plastic housing can become a conductor and the spark will jump through it arcing to ground. Any experience with this? I pulled the whole coil assembly out and put an old set of plugs in it, grounded them, and cranked with the fuel pump relay unhooked and all plugs were sparking. I don't see any carbon tracking on the boots, but there may be some on the plastic thing, not entirely sure but it looks like a black spider web almost burnt into the plastic?

 

yeah if that white plastic spark delivery piece of shit isn't nice clean and white replace it. That part is what I was refering to with carbon tracking.

Link to comment
Share on other sites

Such a bad design, they seem to go bad more when it gets cold I've noticed.

 

When it started misfiring, i was stuck coming out of my drive (icy up hill gravel drive) and traction control started kicking in. MIL lamp started flashing and I didn't think anything of it (throws a gas cap code 3-6x a year). When i pulled into my spot at work, I noticed it was running real rough. All of this on the coldest day of the year so far. The plastic thing I bought from oreily has a lifetime warranty, so if it happens again, I'll be sure to swap it out first.

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...