I have a 88 chevy c1500 with a v8 engine rebuilt a couple years ago. Its cold natured so I have to warm it up if it sits any longer than 45 minutes or so. The problem is when I do start driving it hesitates, sometimes backfires but then clears up after driving a while unless I try to go uphill to fast and then it hesitates and loses speed. It hasn't cut off yet but has come close. When I stop at red lights it starts to shake and idle down and then back up like its gonna cut out. I replaced the plugs and wires and the pcv valve. Hopefully someone else had this problem and knows what can do to fix it

Paul W

• 404 Answers
• Posted on Dec 28, 2008

SOURCE: Low Oil Pressure on 1992 Chevy 1500 Pickup Truck

Hi! The problem you are outlining is very similar to the Rover V8 (Buick engine). We Brit's are used to the low oil pressure when warm. I presume a complete oil change engine flushed with new replacement filter has been carried out? Maybe a top quality synthetic oil with additive may help. You may take it a little further and replace the oil pump with an after market performance up rated one. If you really are worried about low oil pressure damage whilst in low rev's try Molybnenum Disulphide an oil additive which really reduces friction metal to metal wear particulary in the situation you are describing.
That's the best I can suggest at this moment.
Good Luck! and Happy New Year!
Paul 'W'
Onyer~EDson(:0)~[><

SOURCE: 1996 Chevy Express 1500 w/5.0 bogging only when warm.

The cylinder 7 misfire is likely a symptom of the problem, not the problem itself.

Typically, the catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream 02 sensor reading should be fairly steady. Typically the P0420 code triggers the check engine light if the readings of the two sensors are similar. This is indicative of (among other things - such as faulty sensors in the "emissions loop") a converter that is not working as efficiently as it should be.

I do not believe that it is a problem with a valve/head gasket or cam.

SOURCE: high idle CHevy 350 TBI

check if went from a V6 TO V8 need power two more cylinders

SOURCE: 1990 Chevy Scottsdale 1500 wont idle when first starting cold

ICM idle control module, loc throttle body, it may be dirty, remove clean or replace, its easy..

SOURCE: idle out of control.

check all your vacuum hoses and the throttle body itself for a vacuum leaks if the hoses replace as nessasary if to check for throttle body get can of carb cleaner and spray around base of throttle body and sides not in it if idle raises you have a vacuum leak goto a good parts store and ask for a rebuild kit don't goto auto zone or advance they don't carry them