Start up Idle

[Corolla Sound]

Just wondering if anybody elses car (mines a 97 Corolla sedan DX automatic) starts up with a high idle (around 2100 RPM) in park, then after like 2-3 minutes it drops down to around 1100 to 1500 approx. It seems to do it when its not warmed up...Is this normal?

What is the normal RPM when the car is idle in park?

[Kiwi-Corolla]

Yes, that's completely normal. The RPM at idle for the automatic models should be 750 RPM. If it's any higher than about 900 RPM then try cleaning your idle air control valve (IACV). To do it properly you will have to remove the throttle body and give the throttle body and IACV a good clean with carb cleaner. Alternatively, you can leave the throttle body fitted and spray some carb cleaner down the hole after you've removed the air intake hose. I recommend actually removing the TB however, as that way you'll be sure that there are no carbon deposits left to sit down the bottom of the IACV.

[Corolla Sound]

Thanks. I started it this morning and watched my RPM guage. It started up and ran at 900 RPM for about 5 seconds then it quickly rose to 1900 and ran steady at 1900 rpm for about 2 mins, then rose to 2100 rpm while at idle in park. Finally after 4 mins, it gradually dropped down to 1100 RPM and stayed at this idle for 10 minutes until i shut it off.

I am also doing like 3000 RPM (approx) just to maintain 100 km/hr, which seems like the engine is working to hard for that speed (or maybe thats just because my stock engine has absolutely no power lol)

I will look into cleaning my IACV and see if it improves. Thanks again

[Bitter]

It sounds like your coolant temp sensor may be failing, it's common for them to begin to read wrong as they age and act up in the cold. The two wire sensor isn't too expensive. Probably also a good time to replace the thermostat (with new gasket), since those wear out with time. If you have a 4 speed automatic the trans will not shift into 4th gear until the engine is warmed to a certain temperature, a faulty sensor or thermostat will keep you out of 4th which will give you only 3 shorter gears and a very high rpm at highway speed.

[Corolla Sound]

It still starts and runs at 2100-2200 rpm but after driving it and getting it well warmed up (+20 mins), the idle does go down to 650-800 rpm.

[Yodadex]

How do you guys read the RPMs? My little corolla doesnt have a gauge for the RPMs. I like to adjust the RPMs after it has reached optimum temperature. I feel like it needs to be lowered a little.

I just changed the Timing Belt, and drive belts a few days ago. My TDC marks are good. Today ill clean the throttle body and see if that makes a difference which I doubt.

Thanks

[Corolla Sound]

Oops, sorry. I had an RPM guage installed in my car.

http://www.cardomain.com/gallery/15473651

[Yodadex]

I found this tool. non contact laser http://www.ebay.com/itm/Digital-Phot...item256a98764e

[Yodadex]

actually this tool is better. http://www.ebay.com/itm/CORNWELL-AUT...item3cc005efa3 roughly these go for 25. You shouldnt have to pay more than 25 for this type of tool.

[speedy25]

This thread pops up EVERY fall. Maybe this subject needs to be a sticky every September to February.

-SP