LT1Neumann

This is a bit of a long post, just trying to give as much detail as I can. I only know a bit about cars so please bare with me.

Car:
1995 z28 Camaro, 6 speed, w/ catback. Just a bit over 100K miles

The car was running fine then the engine began to bog/misfire in certain circumstances.

• If I was cruising at around 1500-2000 RPM and floored it, the engine would bog/misfire till the car sped up and it was under less stress.
  • This happen occasionally at first, then constantly.
• Felt like it had full power after it was done misfiring
• Didn't show any symptoms when the car it was first starts
• Not sure if heat effected it yet.
• In hard acceleration, my gear stick would rise about an inch or so, not sure if it is normal.

Then car progressively got worse.

• If I gave the car a good bit of gas it would misfire, studder and shake violently. I noticed the gear shifter would shake as well.
• It would occasionally backfire if I let off the gas completely after accelerating.
• Ran fine in some ranges of RPM. Then misfire badly in others. (These are all estimates from memory, may not be exact)
  • From a stop to 1500, it was very rough. I think it pinged
  • While cruising in 1500-2500, it seemed good.
  • Accelerating from 2500-3500 it would misfire very badly and pinged but, I'm not sure what it sounds like.
  • At high RPM it would misfire, ping, and shake
• Temperature played a part in how the car ran, once it heated up the problem got worse. On hot days my the engine would misfire, ping and bog in longer RPM ranges
• When my car temperature gauge was here, it was almost undriveable. It's usually on the second hash mark though.
• My SES light came on long drives but would go off after 10-15 minutes.

One day the car died, it was misfiring the entire time. It had no acceleration.

I brought it to an F-Body performance shop after that. Others and myself thought it was the opti but, the shop said it was giving out no opti codes. They told me there was a hole in the elbow on the intake after the MAF sensor. I was told my car was misfiring, the wires were fried and the injectors were dirty. They put in tr55 plugs, ignition wires and a new intake elbow. I believe they also put in new fuel injectors on some cylinders, not sure. The car was still not running @ 100 percent, and it was giving out codes for misfiring. The shop I brought my car to does very good work, I know my plugs and wires are correct.

The car is now driveable

• Doesn't have full power.
• Misfires slightly through the entire RPM range, it is not off and on like before.
• Misfires heavily when I accelerate from a stop till it gets some momentum.
• I believe it "pings" when I give it some gas, not sure what to listen for but, that is the best way I can describe the noise. -What does pinging sound like?
• Doesn't seem to be any different from when it first starts to after its been running

I was told that my cat could have been clogged with the engine running rich because the MAF was being by passed. Is this possible?

My gear shifter shakes side to side violently all the time. Could something be wrong with my trans or motor mounts?

Edit: When all this started to happen my radiator light would blink on for a few minutes then fade away. I check the radiator and it was full.

The first day I had this car I ran out of gas - I heard that the fuel pump can be damaged if it is ran dry. After I put gas in the car ran fine. These problems came up not to long after this though.

I hope I put enough info to diagnose the problem. I tried searching but I couldn't find anyone in the same situation as me. Thanks in advance for all the replies.

Edit: After reading through what I can find, I'm positive its a clogged cat.

leadfoot4

iTrader: (1)

I'd go at the easy and basic things first. Is the air filter new? How about the fuel filter? Running it out of gas may have stirred up some crud off the bottom of the tank, and pumped it to the filter.

And yes, your "cat" might be plugging up.