cold start

i have 1998 buick riviera in the morring first start runs and shuts off replaced sparks plugs and wires pcv fuel filter just replaced mass air flo w senor have good driveablity does anyone know if ther any adjustments to the idle speed control or wht needs to be done car has 56.000 miles on it first winter this year live in buffalo ny i have to say hello to everyone and my 98 riviera is so nice i love it this is the right club people here know what to drive

Welcome to the club! Need a better description of your problem. Can you keep it running with the gas pedal? If so could be IAC motor.

deekster_caddy wrote:

Welcome to the club! Need a better description of your problem. Can you keep it running with the gas pedal? If so could be IAC motor.

thanks for the answer to possiable problem the car will run without placeing foot on the gas pedel problem is first start in the morring on the second attempt car will start and run normal if you can tell me what a iac motor is thank you

Idle Air Control motor.

What is the idle speed right after the succesful cold start? It should be in the 1200 range and come down to 750 or so as the engine warms up. That's done by the IAC...

Welcome

[h i again after the car starts rpm only goes to 900 or 1000 after engine warms up rpm i about 550 to 6oo should rpm be at 750 to 800 after warm up note some times car will not idle down if i touch gas pedel then it will idle down is the ica motor easy to place in as the mass air flow was

idle speed is 900 ater start up and 500 after warm up

Welcome. Please use punctuation from now on.

Start with the basics. Do you have any error codes ?

There are some cases of cars losing fuel px. Make sure when you start to leave turn the key to the on position for 3 secs, then start. Run nothing but 91+ octane.

Sticky throttle may be caused by several things. A sticky throttle cable, the IAC or worn throttle body shaft. At your mileage, you can probably discard the latter as a potential problem, but your TB may be all gummed up. Follow the throttle body cleaning procedure that is on this forum.

Remove the IAC and give it a good cleaning with carb cleaner. I'm away from my riviera and my FSM, but I'm sure someone can chime in and tell you if there is a reset procedure for the IAC valve that needs to be done after adjustment. Also, if the IAC valve is the pintle kind, do NOT push on the pintle.

You may also be getting erratic maf readings

clean :
- IAC
- MAF : procedure on forum. Be sure to use maf sensor cleaner or contact cleaner. Do NOT poke the filaments.
- Throttle body (don't forget to get a NEW gasket) : procedure on forum

replace:
- TB gasket
- PCV valve. Don't forget to reinstall the O-rings (provided they aren't damaged)

If the condition persists, tell us if the car idles better with the MAF unplugged. This will force your car into what is called "VE" mode. Basically, if it idles better, you will know you've got air sneaking in AFTER the maf.

report back with what you find.