high idle problem

SOMETIMES,when i startthe beast ,it will high idle to ~2000 rpms and will stay there untill i A turn it off and wait about 10 seconds and restart it,then its normal idle) B(put it in gear)

and if that was not enough.....when i get it to idle fine sometimes whil driving the idle will go up all by itself! In gear its ! 1200 rpms;which isnt too bad,but i figure if i fix the high idle at start up i might fix the high idle while driving problem at the same time.


ive replaced the tps with a napa unit and i adjusted it per my F.S.M



89 auto 4.0 non H.O.


anyone have any suggestions?

You would have better luck with this on the OEM Tech board

mine did the same thing. I tore my throttle body off and cleaned it. replaced the TPS from the stealership. Haven't had a problem and that was 4-5yrs ago. '87 with over 230k on it. poor girl needs some TLC.

where is this oem forum?

There is more to than the local forum:

OEM: http://www.naxja.org/bbs/oem.cgi

Modified Tech: http://www.naxja.org/bbs/tech.cgi?

Non-tech: http://www.naxja.org/bbs/nt.cgi

CRASH

disconnect the battery, pull the plug apart from the firewall and clean it, put back together with dielectric silicone grease

high idle

I had the same prob.. changed everything... finally found I had a small crack
in the exhaust manifold by the sensor. changed the manifold fixed the prob.
hope it helps.