93 Z28, auto. All ignition is new, less then 3k miles, ACdelco opti, blaster coil, delco plugs/wires.

I was driving today and all seemed to be ok. The car is running smooth whilst
driving around town, and idles normal.

I was behind a car on the road that slowed down under 10 MPH to turn off
into their dirveway. After they where clear I goosed the throttle in first gear
and I felt the car stumbling so I let off. I stopped further down the road to try it again and it will not even break the tires loose.

The exhaust is also abnormaly strong, buring my nose when I stood behind to have a listen.

Im not ruling out the ignition, the ICM is the original.

COuld it be fuel related?

It runs just fine as long as I dont stab the gas.

Any ideas?

 

This sounds fuel related for sure. Check the fuel filter!

 

Check the fuel pressure and see what it is doing. Have you done anything lately that might have come loose or fell off?

 

Sounds like the PCM thinks the mixture is lean and is adding too much fuel. This could be caused by an intake leak at the TB or an exhaust leak before the O2 sensor, or a bad O2 sensor. Another cause may be a clogged CAT.
Since some work was recently done on the ignition I would check all hoses and wires that may have come loose. You may want to put a scanner on the computer to see if has any codes stored.
97WS6

 

Fixed! Burned plugwire and a small vacume leak at the FPR solinoid thing.

 

my car does the exact same thing, but with more symptoms as well. i've checked for vacuum leaks and replaced all of the spark plugs and i'm still having the same issue. but thanks for some ideas of where to check. glad you got it fixed

 

Where is the "FPR solinoid thing"? There's no solenoid associated with the fuel pressure regulator.

 

Haha im not sure. Its the black small box on the pass side of the intake with a vcume line that runs to the FPR. There was a vacume line that ran to the TB off the front of the "black box" that has a rubber 90* elbow that was rotten. Thats was the vacume leak.

 

I think you are talking about the charcoal canister silonoid. I had just noticed that the 90* elbow on my mine had a leak last month.

 

The vacuum line for the fuel pressure regulator runs directly from the manifold to the FPR. There is no "black small box". But the EVAP purge solenoid is a good possibility.

Let's try a couple pictures... that way if someone finds this thread, and sees a similarity with their problem, they will know where you found the vacuum leak.

Courtesy of Shoebox:

Fuel pressure regulator:

http://shbox.com/1/fp_reg.jpg

EVAP purge solenoid:

http://shbox.com/1/evap_sol.jpg

The EVAP purge solenoid is connected to the throttle body, and to the EVAP purge line bundled with the fuel lines. No connection to the FPR. The FPR vacuum hose is right behind it, but not connected.