My 99 sl2 killed at an intersection one day. i was able to restart and limp it home but still runs poorly at idle. I've replaced the TPS, IDLE AIR INTAKE VALVE, FUEL FILTER/REGULATOR, PLUGS, WIRES AND CLEANED THE THROTTLE BODY (removed, carb cleaner, etc). Is there anything else I should be looking at?

 

Just out of curiousity - during all this work mentioned above, did you disconnect the battery?

 

no, never did.

 

You might have an issue with the EGR system, or even possibly a cracked vacuum hose

 

I did remove and spray out the EGR valve and the two holes under it but it looks like it could stand to be replaced. With 222000 miles just about everything looks like that. it seems to idle high, even on the freeway it doesn't slow much when you take your foot off the gas. At intersections I'll usually put it in neutral and the idle goes up to 2000 rpm, then drops to about 900, unless it keeps dropping and kills. I'll double check those vac lines, thanks.

 

try replacing the engine coolant temp sensor .fixed my neighbors saturn doing that .hers wouldnt start and when it did would run like cr*p,stall out,bog,ect,ect....replacing the ects fixed it right up .it was a 15 dollar part.do a search here on forum for ects.

 

thanks John, that seems to often times be the problem even when it seems unlikely.

 

well i am new to saturns myself and a moderator helped me find this out .
the ects (engine coolant temp sensor)is a very important sensor on this engine .it reports coolant temp to the computer which uses that info to directly meter fuel injection and how much or how little fuel is metered at any given time .

my neighbors saturn had a hard start condition ,would crank and crank and crank befor finally starting ,then it wouldnt run right .i was shocked that a 15 dollar part fixed it right up .
its been my experience that a temp sensor just controlled what you seen on a coolant temp gauge inside the vehicle .but in this motor it does so much more .

seems like you have tried everything else .i am surprised this was not mentioned to you sooner.

so do the search for ects here and read up on its location(drivers side of motor )and pull it out .the early ones had a plastic tip .if its cracked(hers was)thats the culprit.
the new one you buy should be a metal tip .

good luck.

 

John's right about the ECTS creating a bunch of havoc with the engine. My suggestion is to replace the electrical connector that attaches to the ECTS at the same time. It'll cost you an additional $25usd, (GM part), but it fixes a lot of loose connections which in turn makes for a better overall repair job.