ok so i bought a 94 Ranger. She has a 3.0L V6, a 5 speed stick . . . and 227,000 miles The truck is beat to hell but suprisingly runs really well. with one exception. It will idle perfectly for a couple minutes and then it starts to do this weird up and down idle thing. It will be at the normal idle just under 1000rpm then it will drop down to almost stalled, then back up then down . . . and so forth. I have changed all the usual tune up stuff, air filter, fuel filter, plugs and wires and an oil change. what should i clean or replace next to repair this idle issue ?

IAC? or CPS? Those seem to be the things that loved to go on those 3 liters. Im gonna say the IAC though..

does it need to be replaced or can it be cleaned ? i need to buy a repair manual i know ZIP about these motors. IAC i know, whats the CPS ?

You can try cleaning the IAC but with my experience on the 3 liter and even when Ive had my 5 liter it was just a temp fix...itd be easier to just buy a new one...just not from auto zone lol


CPS is camshaft positioning sensor...kind of a bitch to replace(at least it is on the taurus)...and im not 100% sure that is causing the idle issue.


Like i said go for the IAC and maybe bring it to the dealer(tasca flood etc) for a Fuel system cleaning. Find out what company they use. BG makes an awesome product and it does wonders to the 3 liters...just make sure they dont let it back fire haha

Get some throttle body cleaner and spray inside the tb good then start the car and watch the smoke

this thing is a 94' with 227,000 miles . . . dings/dents/scratches in every panel. guy who owned it smoked inside it . . .alot. smells like an ashtray shoved up a bums ass. Bottom line im spending as little as i can on it, its a truck for doing dump runs and home depot garden projects So throttle body cleaner and cleaning the IAC. How do i clean it after i take it off the truck ?

. . . and when that doesnt work where should i look for a good replacement IAC.

you spray it lol

Well if you are looking for a cheap replacement you could probably hit up a bone yard and get one that actually works for like 15 bucks. I dont trust autozone electrical items....theyve never worked for me.


And yeah you just take the IAC off and spray it with TB cleaner..

my 94 with a 2.3 did the same thing... i drove down powerline trails at about 40... when i got back it lost the tailgate and snapped all the shocks off... but no more idle issue

IAC valve or tubing (i need to search for one for my cobra), and also make sure the fuel pumps alright.

I'd put my money on the IAC but there is a chance the TPS could be gone too

id be worried about whatever goop is holding this thing together inside getting flushed out

Check for vacuum leaks too, with my mustang the idle was going up and down due to it.

thats just the naaaaasty cam lol
nah I'd agree IAC hows the timing

thing runs like a top other then the idle issue. I think i just need to buy an IAC. the cleaning thing doesnt seem to keep it going long.