1990 Chevy Corvette Car Stalls after 40 min

IFYOUWANTBLOOOD

MEMBER
1990 CHEVROLET CORVETTE
V8
2WD
MANUAL
42,052 MILES

1990 Corvette
Problem
After Running for approximately 40 minutes the car sputters and stalls. After that, the car will not restart until it cools.
No faults, all gauges in normal ranges
Actions taken:
1. Removed Powerchip and reinstalled stock chip
2. Replaced fuel pump, coil, distributor cap, rotor, ignition module, distributor terminal board, ERG valve, ERG switch, knock sensor, oxygen sensor, MAP sensor.
3. Also verified alternator and battery performance
4. Validated fuel pressure at the rail with ignition, ON, OFF and when the engine stalls. The pressure remained approximately 38 psi. Also verified the pressure does not bleed down once ignitron is off (no leaky injectors)
5. Will pay for a correct diagnosis

2 Replies

MERLIN2021

MECHANIC
17,250 POSTS

What about spark when it dies?
This is from a Chevy Tech bulliten to thier dealers, may be your concern?:
EXPERTEC TSB TECHNICAL SERVICE BULLETIN Reference Number(s): 476503, � Date of Issue: � 01/24/94 Related Ref Number(s): 476503 ARTICLE BEGINNING HARD START ON HOT RESTART/ - INCREASED IDLE SPEED Model(s): 1990-91 Chevrolet Corvette with 5.7L Engine (VIN J - RPO LT5) and Manual 6-Speed Transmission (ML9) Bulletin No.: Chevrolet 476503 Date: 01/24/1994 CONDITION SOME OWNERS OF 1990 CORVETTES MAY COMMENT ON IDLE FLUCTUATION, INCREASE IN IDLE SPEED AFTER A HOT RESTART, AND AN INCREASE IN ENGINE SPEED DURING A VEHICLE COAST TO STOP WITH CLUTCH DEPRESSED. SOME OWNERS OF 1991 CORVETTES MAY COMMENT ON A HARD STARTING CONDITION DURING A HOT RESTART. CORRECTION THE CALIBRATIONS HAVE BEEN REFINED TO ADDRESS THESE CONCERNS. REPLACE THE MEM-CAL WITH THE DESIRED UNIT FROM THE CHARTS BELOW. PARTS INFORMATION

EXPERTEC TSB TECHNICAL SERVICE BULLETIN Reference Number(s): 476503, � Date of Issue: � 01/24/94 Related Ref Number(s): 476503 ARTICLE BEGINNING HARD START ON HOT RESTART/ - INCREASED IDLE SPEED Model(s): 1990-91 Chevrolet Corvette with 5.7L Engine (VIN J - RPO LT5) and Manual 6-Speed Transmission (ML9) Bulletin No.: Chevrolet 476503 Date: 01/24/1994 CONDITION SOME OWNERS OF 1990 CORVETTES MAY COMMENT ON IDLE FLUCTUATION, INCREASE IN IDLE SPEED AFTER A HOT RESTART, AND AN INCREASE IN ENGINE SPEED DURING A VEHICLE COAST TO STOP WITH CLUTCH DEPRESSED. SOME OWNERS OF 1991 CORVETTES MAY COMMENT ON A HARD STARTING CONDITION DURING A HOT RESTART. CORRECTION THE CALIBRATIONS HAVE BEEN REFINED TO ADDRESS THESE CONCERNS. REPLACE THE MEM-CAL WITH THE DESIRED UNIT FROM THE CHARTS BELOW. PARTS INFORMATION