Buffalo

I've got a 2002 Camaro Z28 with an LS1. The engine misfires bad. The engine as well as the whole car shakes because of it. Now I've changed the spark plugs and the wires and it still misfires. It runs a little smoother now, but I can still tell that the misfire is still present and the the engine shuts off when I rev it at high RPMs. I'm thinking that the ignition coil packs need to be replaced, but haven't done so yet since it will be expensive to replace all eight of them. Tell me your opinions. Thanks.

RPM WS6

iTrader: (3)

If it were my car, I'd hook up a scanner and look at specific cylinder misfire data and DTCs, for starters. My next steps would depend on the results of that data.

Buffalo

Yeah, thats what I did. I took the car to the shop to get it diagnosed earlier today. Hopefully, they figure out whats wrong with it soon.

Elthesh

iTrader: (1)

Wouldn't surpise me if it was the O2 sensors. My car ran like hell and shook when I hit a puddle till they finally dried off.

Buffalo

I have a feeling that it might be a cat converter sensor. Would a bad cat sensor cause all of this?

RPM WS6

iTrader: (3)

The "cat sensor" would be the rear O2 sensor(s), and this sensor has no bearing on how the engine runs. So to answer your question, no, a bad rear O2 sensor will not cause any of those issues. The only reason you would even know it's bad would be an SES light, but the engine would run the same as normal. It's the front O2 sensors that actually have an effect on engine behavior, and if one of those was bad you could have some noticeable driveability problems.

On the other hand, a bad/clogged cat(s) could cause the issues you're having. So if you are getting cat related codes in addition to the poor engine behavior you've mentioned above, I would suspect a possible bad cat(s).

Buffalo

I'm thinking that a clogged cat is the problem. When I got it scanned for codes, it said that my cat sensor was not getting any voltage and now it doesn't throw that code anymore. The exhaust really stinks and it leaks out the tailpipe when it starts up. I took it to a shop to get it diagnosed, I should know what the problem is by tomorrow.

1999maro

Yep, most likely a cat issue, now you just need to cut it off, lol

Buffalo

Well, we were all wrong. I got the car fixed and it runs great now! This is what was wrong with it.

One broken little valve spring.

skeeter99

iTrader: (16)

Nice car man!!

Buffalo

Thanks for the compliment.

elwood2

iTrader: (5)

How much did they charge you to diagnose and replace the valve spring?

Buffalo

Total cost was $447. I would've done it myself, but I don't know enough about the car to take apart the top end and I needed to get it running. This car is my daily driver.

cowboysfan

I'm surprised you or anybody could'nt hear any rattling in your motor..... your lucky the broken valve did'nt cause major damage.