Engine straining when starting

[gladis]

Hey all,

I've noticed for the last couple weeks, whenever I start the car after 2-3 days of non-usage (summer's here, I don't drive my DD as much), the engine strains a bit after about 5 seconds before coming back to normal.

The sequence goes something like this:

1. Start
2. Shift into gear 5 seconds later
3. Tiny bit of gas
3. RPMs dip, abnormally, not just down to 750 like normal, it feels like it could stall, but recovers.
4. Goes to normal.

I'm not sure if steps 2 and 3 are important, as I haven't just started and waited to see if it drops in RPM anyway.

This only happens after at least 2 days of not using it, and it's not cold here, 50-60F is as low as it gets.

[Kep]

Does this only happen when the car is cold or would it also happen if you drove it, stopped it and restarted it right away?

My initial thought was that your throttle body might be gumming up or your EGR valve may be clogging up. It wouldn't hurt to clean these yourself (not extrememly hard). If you take it into a mechanic they will probably clean the throttebody and replace the EGR valve (kind of expensive).

Kep

[toyomoho]

Might be the IAC valve sticking or Park/Neutral switch.

The ECU should increase idle when the selector is shifted out of P or N to compensate for the load of the trans.

[gladis]

It only happens when the car is cold, actually, when it hasn't been driven for at least two days. I'll try to start it tomorrow if it happens in less than a day (may be intermittent)

I know definitely it doesn't happen if I stop, and start, since I went shopping today, and when I restarted it was fine.

I'll take a look at the things you mentioned and get back to you. The TB should be fine, I had the mechanic clean it a few months ago.

Could old oil be a cause? My oil needs a changing (about 4,500 miles old now)