Thread: Engine Miss? (Low power, lots of vibration, "blub blub" noise from exhaust)

1997 GTP 4 Door, ~225k miles

I noticed coming of the interstate off ramp yesterday at a red light that my car was shaking quite noticeably and emitting a "blub blub blub" noise from the exhaust. As I accelerated from the light, it seemed down on power to me.

I am uploading a video to Youtube now of the engine running and the sound coming from the exhaust.

It isn't as noticeable in the video as I had hoped, but maybe you guys can get me started in the right direction.

I will post the link when (if) it ever finishes uploading.

Thanks!

Exhaust leak at the resonator will cause that, had it happen the same way almost.

Engine Miss?: http://youtu.be/bbbsTMcljX8

There's the youtube link. Hopefully it helps clear things up.

Yeah, it's still coding for a crankshaft position sensor even though it's been replaced and codes cleared.

Check for exhaust leaks.

Update:

Replaced all the plugs. Very disheartening after such a battle that it didn't solve the problem. (The rear one closest to the driver's side was a real bear!). They were looking kind of rough, so it needed doing anyways I guess. The passenger rear one had a lot of oil on it as well.

I unplugged all the wires at the coil packs, and they are very corroded. I might want to do coil packs and wires too while I'm at it.

The check engine light is now flashing, so I might get that read at Autozone tomorrow.

Also, just for S's and G's I unplugged the IAC with the car running and nothing changed. Same with the MAF. Don't know if that means anything.

I'm off to bed, defeated for tonight. 14 hour shift starts in 6 hours Hopefully I can limp it to work in the morning.

Ok, I'll try new wires and cleaning the coil terminals tonight.

Noticed on the way to work today that while pulling a hill under normal throttle, it bogged down like it was going to stall. Revs dropped and it would intermittently go to full boost.

More throttle didn't seem to help.

Just left Autozone with new plug wires, electronics cleaner, and some grease.

While I was there, I got them to pull codes. Here is what they pulled:
P0341
P0300
P0122
P0366

I am also uploading a clip of me pulling the hill that gave me trouble this morning. It isn't as bad in the video as it was early this morning.

I'll post a link when it finally uploads.

Car Diagnostic: Exhaust noise, low power, miss?: http://youtu.be/cOwZaGepAdg


Here's a little clip pulling the hill I had trouble with this morning.

Ok. Should I clear the codes after I do b plug wires?

OK. Did plugs and wires, but that didn't help any.

Guess I'll start on P0122 next :/

*UPDATE*

Last night in chat, member RareGMfan sent me to a link to trace down an engine miss.

First step called for a cylinder check by unplugging each injector to determine which cylinders were affected.

Cylinders 1, 3, and 5 checked out.

4 and 6 I couldn't get unplugged on my short lunch break.

Unplugging number 2 yielded no change in the way the engine was running. This is the same spark plug that had quite a bit of oil on it when I changed it, if that means anything.

I assume the coil for 2 and 5 is ok since number 5 passed the cylinder check.

Your thoughts?

Also, I noticed today that the miss didn't show up until I had been driving a bit and reached operating temperature.