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When initially starting my B2 2.9, it starts them stalls unless you give some gas quickly. This only happens when the engine is cold. After a few seconds of manually giving it gas it runs great. It's like a older carb that the choke doesn't work on. I have checked and all vac lines are in place. I have replaced the plugs and checked the timing. Plugs were worn but not real bad and timing was right on at 10BTDC. Idle is at about 1000 in park and about 800-850 in drive. I have checked my manuals and can't find anything on what might be causing this. It's not the end of the world but I'd rather it started and ran without having to hit the gas before it stalls out. What controls the starting idle speeds for cold starts?

Wish they had never depended on computers to opperate a vehicle. It was much easier with an engine, carb, points, plugs and none of electronic crap.

There is a IAC valve that controls the cold start. They tend to clog up with junk from the motor. take it off and clean the port going to it and the IAC motor itself. Unless the IAC failed, that probably should help. The IAC is a approx. 6 inch cylinder either mounted on the manifold by the throttle body or it is mounted on the air box. It should have electrical wires coming off of it.

Thanks. I checked the motor and the resistance was well withing the specs. Removed the body and it didn't look too bad. The shaft inside was free and only some carbon inside. I just put it back on and made sure it was sealed well at the gasket. Started the engine (has been sitting for about 8 hours) and it fired up and didn't stall. I'll check again in the morning. Maybe it was sucking air at the gasket?

LarryA,
I was just messing ith my IAC valve too and FWIW:

the Chilton book said it should have 1 volt at the wiring harness plug ... I think with the key on but not running. Also, with it on the car, not plugged into the harness, engine running, if you apply 12 volts to the solenoid the idle should raise about 1000 RPM. (If you apply that same 12 volts with the valve off the car you can see the plunger stroke about 1/4". I'm curious ... what ressistance value did your manual give you for the IAC? (My book gave nothing).

My idle is erratic at times... not consistantly a problem. Usually happens on warm start-ups, it sometimes idles so low it dies or when put back in PARK the idle falls off too far and it may stall.

I also pulled, cleaned and re-gasketed the throttle body... four 6mm bolts. I t does'nt really have any small orifices that could get clogged, but I didn't know that 'till I saw it. They can get some heavy black build-up in the throttle bore around the edges of the butterfly plate though.

Enough time hasen't passed to know if I cured anything. dave

Hi Bower100. My Chilton manual has the following for checking the IAC valve:
1. Turn inginition OFF
2. Unplug the harness from the IAC valve
3. Using an ohmmeter, measure the resistance between the terminals on the valve.
**Due to the diode in the selenoid, place the ohmmeter positive lead on the VPWR terminal and the negative lead on the ISC terminal.***

From the diagram in the book, it shows the VPWR terminal as the one that comes from the power relay. On my engine this was the pin to the left facing the engine. I take it that if you test backwards you can fry the diode.

4. Resitance should be between 7 - 13 ohms. If not then replace the valve.

Hope this helps.