2002 Sienna stalls when engine is cold

Hi,

I have a 2002 Sienna. It runs great until recently. When the engine is cold, I need to pump the gas pedal and turn the key to start the engine. After the engine is ignited, I release both the key from START position and the gas pedal, then the idle drops to zero quickly and the engine stops.

The only way to start the engine is to turn the key to START, crank the engine, press on the gas pedal to maintain the idle speed (above 1000 rpm) to keep the engine running, release the key, until the temperature climbs up. At this point the idle speed is back to normal (about 750 rpm in neutral after releasing the gas pedal) and the engine won't stop.

What is causing this problem and how can it be fixed.

Thanks.

Joe

Reply to
Joe Wang
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I sounds like the engine is not getting cold start enrichment. I'd check the idle air control valve and ask qslm for his opinion ;-)

Reply to
Ray O

I've seen a handful of 02 siennas with idle air control valve problems. When the engine in cold the valve needs to open more as the engine needs more air during this period. If the valve is unable to go through its full range of motion and open completely then the engine will stall. Another thing that I have seen plenty of (still relating to the IAC) is squirrell or mouse nests in the air box. Lots of times these guys will store seeds and the like in there and debris will make its way down the intake tube and block the IAC valve.

Reply to
qslim

After having a mouse nest in my air cleaner box, I made a screen out of

1/4 inch hardware cloth to cover the intake port.

---MIKE---

Reply to
---MIKE---

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