My pinging is so bad a mini van passed me.

[95BLKGT5.0]

My pinging problem is so bad it sounds like the lifters are floating.
I have run a test that is in the quote below and did what it said. It will not ping cold but at normal oper. temp it pings bad so bad that I will not drive the car.
As soon as the car gets to about 180 deg it pings so bad above 2800 rpms that a freaking mini van passed me going up an on ramp, so I drove home and parked it and have not driven it sense.
This is what I have done to the car.
1) New plugs,wires,cap,rotor
2) Timing set at 8%
3) Cleaned MAF
4) New K&N air filter
5) New ACT
6) New ECT
7) New thermostate 180%
8) New 02 sensors
9) New 190 fuel pump
10) New Kirban AFPR (fuel pressure set at 41psi)
11) New fuel filter
Miles on car 100,090
I did not want to hijack someone elses thread so here is a quote from someone elses thread.
I did the test in the quote warm and cold and I do have a autometer temp gauge so I am able to tell what temp I was running at.

QUOTE]As for problem #1, there are many things that can cause pinging. But I want you to perform a few tests for me. When the car is bone cold (sat for at least 8 hours), drive the car, and see if it pings at part throttle, and wide open throttle.

Next, once the car is warm, do the same. See if it pings at part throttle and/or wide open throttle.

Wide open throttle = WOT = pedal completely to the floor. It is very important that you test the car when it's cold & warm, and part/WOT throttle during cold and warm states.

The sensors that the computer uses to calculate a/f ratio depend on whether the car is warm & what position the throttle is.

Perform those tests, and shoot me a PM and let me know what happens. Then we can go from there. I have a suspicion, but I want to confirm it first.[/QUOTE]

 

[94TURBO5 O]

Pull the spout and set the timing @ 24 degrees and leave out the spout. You'll lose a little power but the pinging will go away for sure.

 

[89 blue lx]

maybe i missed it but what octane fuel are you using? this is prolly a stupid question but always a thought

 

[Silver85TC]

You need to check for any computer trouble codes.

Also, have you deleted the EGR valve? If you havn't, make sure you're EGR valve is functioning correctly. If the EGR valve is not opening when it's supposed to, your a/f mixture will be lean........resulting in pinging.

 

[Tahoe GT]

I had the same problem on my new 95 GT with 99,000mi. Here's how I fixed it:

On the backside of the MAF there is a plate that directs the air that the wires see, down that column. I pulled that plate off, cut it flat just above the upper screw hole. Now, set the plate back in place and you will notice that it partially covers the MAF metering tube. I took a round file and shaped a half-circle into the plate to provide better air flow through the metering tube. Put it all back together. Pinging is gone!!!

Do you have to do all that? I doubt it. Just remove the plate and stash it and the screws in a safe place for later use. I removed the plate and the ENTIRE post leaving only the sampling tube on my 96 GT and gained 1.5 mph in the 1/4 mi. Nice improvement for 20min labor. Good luck.

 

[mo_dingo]

The computer ****s off the EGR at WOT, so it can't be that.

Like I said when I PM'ed you, check your fuel pressure, and hook up a vacuum gauge. It's a start.
Scott

 

[94twinscrew]

just my $.02,but if you didn't index the ACT correctly,you would still ping.If the incoming air doesn't flow thru the eye of the filament,and it ends up going around it,...then that may be your problem.I would pull the ACT out,and make a pencil mark on both sides of the eye(loop),and reinstall it so that either mark is pointing up to a 12 o'clock posistion.This way the air is forced to flow thru the sensor,not over it.

 

[Silver85TC]

As soon as the car gets to about 180 deg it pings so bad above 2800 rpms that a freaking mini van passed me going up an on ramp

The computer ****s off the EGR at WOT, so it can't be that.

He didn't say it pinged at WOT. He said it pings above 2800 rpms once the car is warmed up (closed loop). It most definitely could be the EGR valve (or lack of it if it's removed/not functioning).

 

[Swarzkopf]

My bet: Your MAF.

When I first bought my 95 GT, it would spark knock as yours is.

I figured the motor wasn't getting enough fuel, so I checked the fuel system and found it okay. I then bought a 190lph fuel pump and adjustable regulator and cranked up the pressure. This helped the pinging, but it still detonated sometimes, and other times it would bog and feel gutless- like it was running really rich.

At that point I figured it could be the MAF not giving the EEC the correct readings and resulting in a wacky, variating air/fuel ratio. I replaced it with a Pro-M 75mm. The difference was immediate and HUGE- no more pinging, and the car felt much more powerful.

I am positive the problem was the MAF on my car, and would suspect the MAF on yours. I believe that alot of the reported 95 5.0 detonation problems probably have something to do with a faulty stock MAF.

There are three main sensors your EEC uses to determine your air/fuel ratio- the MAF and your two 02 sensors. Being that you replaced the 02 sensors.....