truck idles weird

[Ranger4657]

not sure whats causing this, ill jump on the highway and as i apparoch a stoplight and stop the idle sticks at 2500 and some times even at 3500, and then jumps down to 1000 then back up, any one have any suggestions on places to start?

 

[bigcountry]

check EGR,plugs,wires fuel filter might even help if a bit and i see on ur profile that u have a 1000rms if u have a stock alternator u might want to check to see if the truck isnt tryin to over compensate by keepin the idle up to keep everything goin and keep the truck from diein. i could be wrong on that but hey hahaha it never hurts to throw it out there. but with all kiddin aside check the common problems like i said before my little ramble and see if that makes a difference and i forgot to say the maf might be dirty

 

[michowski]

Does your throttle cable bind at all? I know when I purchased my 93 ranger I had issues like you described. Ended up on mine being the throttle cable casing being really rusted and causing the cable to stick on the inside.

 

[Ranger4657]

well i changed plugs, wires, coil, dist cap and rotor like 3 months ago and it never fixed the problem, ive changed the rabs sensor, and the fuel filter about 5 months ago, the problem has been there sence i got the truck, the high output sound system doesnt make a difference, ive got 0 ga. wires throughout the charging system to compensate for the load and a cap killer and audio battery.... so i doubt its that...
and on top of all that ive cleaned the maf several times sence ive owned it.

the only thing that comes to mind is a temp idol switch? im not sure if our trucks have them but maybe? i had a probem with the truck over heating and a bad water pump when i first got it, maybe that tripped something?

 

[Ranger4657]

Does your throttle cable bind at all? I know when I purchased my 93 ranger I had issues like you described. Ended up on mine being the throttle cable casing being really rusted and causing the cable to stick on the inside.

im not sure how to test to see if its binding, ive done the zip tie trick on the linkage at the gas pedel and never noticed any binding, ive also tried to pull the gas peddle up with my foot when it happens but never have any luck getting it to idol correctly again,

only solution is to shut it off and wait about 30 secs then start it up again and it runs right.

 

[bigcountry]

im pretty sure that it could be the temp sensor

 

[Ranger4657]

wheres the tmp sensor located on our 3.0's ? is it the sender that feeds the temp gauge? also i was looking at the chiltons book and the IAC valve on the throttle body seems like it could be a potential suspect for this, not to sure though

 

[Ranger4657]

yeah ill run the tests to check the resistance on it and go from there tommrow, it sure wil be nice to fix this, been buggin the crap outta me lately

 

[Ranger4657]

well i tested the iac valve and it had a resistance of 13.3 ohms, the chiltons spec's it between 7-13 ohms... what can i clean the valve with (not the contacts)? im wondering if i clean it ill get a better reading and perhaps solve the problem... the inside looks like it has quite a bit of carbon build up... im reluctant to buy the part sence its like 60 or so bucks...