trhs75

My '99 seems to have developed a rough idle which also feels a little slow, and the normal auto-trans "creep" isn't present on level ground. I checked for codes; none present. The idle feels rough both in neutral and in drive. It seems to smooth out when the RPM's are higher. Someone may have an idea. Thanks for reading!

salimshah

You did not mention how many miles. Also you did not mention the idle rpm.

Has the IACV ever been cleaned? 65-70k it needs cleaning. We have a DIY on it.


Salim

trhs75

Hi, Salim!
It dawned on me as I was typing that up that I didn't pay attention to the RPM -- it seems to me it was about 800 or so. This one has about 82,000 miles. I had cleaned the IACV on our other one with about twice the miles, but not on this one. I'll have to give that a try. I always appreciate your perspective, Salim -- thanks for your help!

salimshah

Once the engine has warmed up the idle should 750~800 and cold around 1100. These numbers are in Park. In drive with foot on the brake tend to drop about 50 (delta).

Other things to check would be spark plugs (misfire would generate CEL but a weak spark can cause loss of energy.
Air filter.
Fuel ... has the tank been filled recently ... stale gas also gives problems. Worst is when water gets in the fuel.

Salim

trhs75

You were right again, Salim! I had forgotten what an easy fix that was. It seems to have solved the problem. It's garaged and out of the weather for now, but I'll see how it does out on the road. Thank you!