Heres a real head scratcher. 99 Lumina ltz
Ok, I have a 99 ltz 82,000 miles 3.8 200 hp ltz pcm. This is a strange mess, Ive owned the car since 01 and no one besides myself works on it. 30 yrs. ase master tech...<br /><br />Decided to take the family to Disney in Florida, from Southern Illinois.The drive down was great not a hiccup.
The way back was a whole nother situation. The Beginning was great the first time i got off of the highway the trans acted like it was still in TCC lock up, I manually shifted down into first and that seemed to help get me off the exit ramp to a safe place, got out with the engine running and checked the fluid level and condition.Full and not burnt.
Turned the car off with the thought it was an electrical fluke or whatever. Got back on the highway and all was well for a few miles then the tach jumps to 21-2200 rpm and acted like it had down shifted but it free revved between idle and 2200 rpm no brake action at all then i scan the dash and the airbag light is flashing and the abs light is on? Shut off the engine in neutral and restarted it, issue cleared itself. this progressively got more frequent as the day went on until it started cooling off outside. after that it was smooth right the the house.
I took it for a ride yesterday and it started again on the return trip. got home and hooked the snap on up to it, no codes no pending codes and mode 6 shows a minor evap leak, egr decel test failure, (probably some carbon) and it also failed an idle efficiency catalyst test. Nothing else, test drive with the scanner showing live data show no issues. TCC working properly, shift times in the .3-.5 second range.and it hasn't acted up with the scanner running. for the next while i guess ill be traveling with the scanner on the seat.
Any ideas? ever happen to anyone else? Its too cold and wet here to go out and check around under the hood but this really has me scratching my head.
Thanks Folks
Slim Jim
The way back was a whole nother situation. The Beginning was great the first time i got off of the highway the trans acted like it was still in TCC lock up, I manually shifted down into first and that seemed to help get me off the exit ramp to a safe place, got out with the engine running and checked the fluid level and condition.Full and not burnt.
Turned the car off with the thought it was an electrical fluke or whatever. Got back on the highway and all was well for a few miles then the tach jumps to 21-2200 rpm and acted like it had down shifted but it free revved between idle and 2200 rpm no brake action at all then i scan the dash and the airbag light is flashing and the abs light is on? Shut off the engine in neutral and restarted it, issue cleared itself. this progressively got more frequent as the day went on until it started cooling off outside. after that it was smooth right the the house.
I took it for a ride yesterday and it started again on the return trip. got home and hooked the snap on up to it, no codes no pending codes and mode 6 shows a minor evap leak, egr decel test failure, (probably some carbon) and it also failed an idle efficiency catalyst test. Nothing else, test drive with the scanner showing live data show no issues. TCC working properly, shift times in the .3-.5 second range.and it hasn't acted up with the scanner running. for the next while i guess ill be traveling with the scanner on the seat.
Any ideas? ever happen to anyone else? Its too cold and wet here to go out and check around under the hood but this really has me scratching my head.
Thanks Folks
Slim Jim
Last edited by Slim Jim; Mar 21, 2018 at 10:13 AM.




