Hi Group,
>
> 1999 Ford Ranger 4 cyl., 5 speed man.,105,000 miles, I have put every mile
> on it. At 104,000 miles put in new plugs & plug wires (1st time), air
> filter, fuel filter, PVC valve (2nd time). I was beginning to have a very
> low idle RPM, which would cause the truck to stall, it was getting worse so
> figured it was due for a tune up. The truck ran smooth otherwise. Since
> tuning the truck up the very low idle RPM does not happen all the time only
> every once in awhile, very random. Some days it runs great all day, other
> days it idles poorly all day, some days it comes and goes. If there was a
> way to set the idle RPM I believe my problem would be solved, but the
> computer controls all that, the truck does not have a tach so I can't give
> you a RPM number. The truck passed emissions testing no problem after the
> tune-up, it was idling fine when I went for the test. It has never failed
> the test before. Anyways what could cause this very random idle RPM problem?
> If I took it to Auto Zone and had them hook their computer to it would that
> tell me anything? Thanks for any ideas.
>
> Ken
>
>
>
Hi Group,
Just wanted to let everyone know what I have found so far. On another discussion board someone suggested tapping on the IAC solenoid, which I did with the plastic end of a screw driver, started the truck up and everything was idling just fine. So does that mean the IAC is bad? Or do I just tap on it when it acts up again? The IAC is $111.00 from the Ford dealer. Also found someone suggesting cleaning the MAF sensor, helps with idling and pinging problems. The MAF is $187.00 from the Ford dealer, with a $75.00 core charge. I did notice that the MAF has a drop of glue or solder on one of the torx screw heads, and the other screw head has a small post sticking up so you can't use a regular torx screw driver, so I guess they don't want you opening this unit up. Wonder if they will still give you the $75.00 core charge back if you do open the MAF up?
Thanks, Ken