OK omniscient ones, what do you think?

[Dmb408]

I am getting a really rough idle starts (lasts about 30 seconds) on VERY cold starts only. These are when my car has been sitting in the teens or lower (read 15 F or below) temps for the entire work day (read 9-10 hours) and then I go out to start it. It goes away once the car warms. I was able to catch it doing it today with just my basic code reader in the car and pre-hooked up for this reason and it basically went away when coolant reached 90 F (again, after about 30 seconds). That is just an extra data point I have to add; don't believe coolant temp necessarily has something to do with it. For contrast, our at-home garage is attached but we keep the hvac duct shut, so it has been getting into the 40s overnight and the car doesn't have this issue starting at that temp.

The MAF data looked fine on my basic reader, degrees of advance maybe looked low? What should those be in a cold start in simple degrees?

What could it be? I have done timing belt, with thermostat, and ECT sensor recently. Car has new battery and new voltage regulator. I am running Redline 5w-40. This is really annoying me because I have done so much premptive preventative maintenance this year, and this really gets me on this "why do I own this car" band wagon as opposed to the "man this car is awesome" band wagon.

As always, thanks for the two cents.

[4everRS]

Not sure. The only thing I'm thinking is when the car first starts up, the sai runs for 30 seconds to a minute. If water is somehow getting in the pump and freezing?

Otherwise it some kind of fuel delivery problem.

[lswing]

Funny, I thought either sai or fuel....older fuel filter freezing up some? Condensation freezing in air filters causing flow issues?

Just go run the car for 10 during lunch.

[Dmb408]

I know i have tried to go out for lunch more, and actually drive somewhere. I have doen air filters recently and i always wipe out the air box when i have it off or when i did the air filters. I think it might be fuel too, i tried to do the filter last time it was in the shop (tack it on to what was getting done) but I think i might just do it myself.

[905084]

The car will run fine with or without SAI when cold. I have one with and one without, but I think SAI is the right track. How about vacuum leak from the SAI vacuum solenoid? Both of mine had SAI vacuum lines that were no good. Plug the output of the SAI solenoid and see what happens.

[alrightroad]

sai. mine has exact symptoms. started about 3 weeks ago. Finally got code bank 2 sai intermittent (or whatever the wording is) a few days ago. cleared code and it hasn't come back but sai is a little louder than it has been in past on cold mornings.

[Dmb408]

905084, so by output of the SAI solenoid, do you mean the output of the valves on each cylinder bank or the main output run from the SAI pump itself?

[905084]

905084, so by output of the SAI solenoid, do you mean the output of the valves on each cylinder bank or the main output run from the SAI pump itself?

The SAI has a solenoid on the top of the intake that activates and pulls both the SAI valves on the back of the heads open the first time the cold motor is started. If you pull the carbon fiber intake you should see it.