I've searched the forum and read about the 302 motor doing this. My truck has always done this but as of late its been different. I used to be able to hit the gas and it would idle down from the high idle position. Now it doesn't do that anymore and it idles high for close to a minute. I've been just waiting it out until it decides to idle down but a few times I've been in a hurry and just put it in gear. I don't like doing this because it jams it in gear at high idle and jerks and sounds bad on the trans. Could this be solved by cleaning out the IAC or is it somthing else? I'm not sure where the IAC is even located at or what it looks like to be honest.

Thanks in advance

 

On start-up right? They all do that. But you're saying that now the idle won't drop even if you blip the gas pedal? When it's warmed up what's the RPMs at idle? Should be around 650.

 

Check your throttle positioning sensor- this is what the computer uses to control the idle when its cold and makes it switch from higher to lower idle. If you have a service manual it can tell you the procedure for checking them.

 

yeah even when i blip the gas it won't idle down. I'm not sure what my RPM's are I can just tell from sound its idling high. It did this before but like I said not as long and with a blip of the gas it would go away. I'll have to look in my owners manual for that part that was mentioned

 

Your IAC is located on the TB facing the truck, it would be to the right of it. The TPS is located underneath the TB and the easiest way I've found to replace it is to take the TB off. There's nothing to it, just remember not to over tighten the bolts so you don't crack it.

 

I talked to my mechanic this morning and he assumed it was the IAC as well. I went out and replaced it on my own but it seems to do the same thing but it doesn't idle high as long. It still won't idle down when i blip the gas. It was warmed up I would say and I shut the truck off. I let it sit for 10 seconds and started it again, it idled high for 10 seconds then went down to a lower idle. Should I look into changing the TPS or how can I tell if it is bad? My mechanic also said somthing about setting the IAC after I install it, he mentioned driving it around 40 MPH for 5-10 minutes. I did this. Not sure if anyone else had heard of that or if there is anything else I should do

 

I would wait and let the IAC works itself in, have you cleaned out your TB yet.

 

I unplugged the IAC and then unhooked the battery. I hooked everything back up and it is running normal again. I did not clean out the TB, should I and why?

 

God you sound like Gordon ramsey on hells kitchen(1st nominee and why), you should clean it out to get rid of the crap that could be in there. It to could be part of the problem. Spray you some carb cleaner in there with the motor running while holding the throttle cable open a little and let that stuff blow right out the tailpipe.

 

Sounds like a plan lol and I'm not sure if that is a complement or not. I run some of the lucas injector cleaner through it once in awhile. The IAC was full of gunk and build up. Thanks for the advice about the TB. I'm thinking about replacing the radius arm brackets as well because they are rusted out. They have been replaced several years ago because they aren't rivited on they are bolted on. Is this a big project or simple as it appears. Only thing I could forsee a problem would be getting the arm out of the bracket. Anyone have experience with this?

 

I meant nothing bad by it, I just thought about it read your last post. Just sounded real direct. Hope that helps you with your truck though.

 

Since the RA brackets are bolted you can easily remove them from the frame in order to pull the RAs. Shouldn't be a big job at all, you got it good. Just do one side at a time.

 

Okay thanks alot. It should save me some money doing it myself. I had my mechanic order them from ford but I'll just tell him I'm going to replace them myself and just have him check out my front end. I like taking it in 2 times a year for a once over.