Rough idle/dying

DRAG N FLY

MEMBER
CHEVROLET CAPRICE

1995 Caprice wagon 5.7 LT1 {engine swap in the 90s} A/T. The car was running fine yesterday. Got in it this morning and ran well. Went to work on the freeway running fine. Get in after work and it did not want to start and when it did it ran rough. Put it in drive and it lunged and kept a high idle. Picked up my daughters and had the A/C on {we live in Phx, AZ} and it died when I put it in park. It never did this before. Any help would be great.I worked on VWs for much of my life in dealers and privat owners. But never worked on a Chevy before. Thank for your time Larry

1 Reply

MUSICMAN_1968

MEMBER
2 POSTS

I have a 1992 Caprice that I bought used. When I got it, mine was doing basically the same thing. It would run fine at highway speeds, but would sputter and die at idle speeds (like driving in parking lots). I ran a diagnostic on mine, but it didn't trigger anything. Next I replaced the idle air control valve (IAC), but that didn't help either. Finally I tested the EGR valve, although it was holding vaccuum, it was opening up too soon. A test you can try is the unplug the vaccuum hose from the egr valve, and plug the vaccuum hose with a small screw or bolt. If it drives fine at that point, replace your EGR valve. I hope this helps. Good Luck