99 Cadillac SLS
 

Ok, had the headgaskets replaced, changed water pump, and belts, all hoses checked, thermostat replaced, and car runs great except for at times, the temperature gauge will shut over to 3/4 for 2-3 minutes, then go back to the 1/2 way mark. Took back to the mechanic, and burped the system again. Drove for 4 days 100 miles a day with no problems. Yesterday driving fine, and all of a sudden, boom, shoots over to hot, says a/c is shut off, engine hot. Immediately pulled over, let cool for 5 minutes restarted, and then it was fine. Let run for over a half hour sitting with it in gear, no problems?

I ran the codes because the service engine light is on, the abs, and traction control, and here are the results:


B1310-Ambient air Temperature Sensor Failure-Current
C1255- EBTCM Internal malfunction-Current
P1645-Evaporative Emission Purge Solenoid Control Circuit_History


Any help or advice on this would be greatly appreciated. Thanks in advance. I even reset the codes, service engine light would go off, then came back on, and now even if I clear codes, still stays on.

RE: 99 Cadillac SLS
 

Is there anything it particular going on when it happens? Northstars are a little scary in regards when head gaskets are replaced there is always a chance it wont work even when 'time-sert'ed. It might be worth having CO test, to be sure engine is still sound.

RE: 99 Cadillac SLS
 

No car is driving fine, just drove it over 100 miles with no problems for overheating?