[JoeS]

Hi folks.. Well.. I finally got a scan tool hooked up to my car and was able to gather some information about whats going on. Only problem is that I need some help reading this information.

Here is the original thread describing the problem:
http://hotrodders.com/showthread.php?s=&threadid=21189

Here is a link to the csv (MS Excel) file containing all the scan tool data:


SCAN TOOL DATA

Anyone have any idea whats going with my poor L98?

Thanks guys!

[2-manytoyzs]

My experience comes from 30 yrs as a Ford driveability tech so take this for what its worth. The last GM I worked on had similar symptoms. Turned out to be a PCM. That was deducted by looking at all the inputs and outputs from the PCM thru the scan tool. All readings were normal. I found out that the previous mechanic that worked on the car had replaced the starter and shorted the batt terminal at the starter to ground. The car never ran right after that and they replaced all kinds of stuff trying to find the problem. Shorting the batt wire to ground blew the PCM. Dont go out and buy a new PCM now, but my experience is the after you have checked all data and it looks normal, that the PCM could be at fault. PCM diagnosis is a process of elimination. It will never tell on itself. It could give codes on ign, or fuel related problems, but has no way of self diagnosis for internal failure.

[JoeS]

bump..

Anyone have any ideas whats going on? The injector pulse width seems excessive to me, anyone know what a regular pulse width should be?

Thanks guys!

[drlindz]

After looking back on the original post, the best thing that I can suggest is to take it to a Chevy dealer to have it diagnosed.

I say this because sometimes a problem in the computer controlled systems on a car just won't make themselves apparent.
I recently ran into a problem with a late model Firebird. After days of running scans and checking everything I could possibly think of, I was no better off than when I started.

Took the car to a GMGoodwrench Service Center. I have no idea how they figured it out, but it turned out to be a problem with the ECM. This didn't show any codes so I had no idea that it was bad. I replaced the ECM myself and the problem was solved.

They deal with this sort of problem on a daily basis and have testing equipment that most could'nt afford in a lifetime.

It cost $80 for them to tell me what was wrong and that was well worth it considering all the time and frustration that this ordeal cost me.