What exactly was tested? What was replaced and why?
idle problem
I have an 89 302 auto
in the morning when I first start it, it will jump up to around 2200 rpm and fall back down bogging itself out and back up around 2200 and down a few times and will idle high for a while. I know thats not normal and had it at a shop after I messed with it for 2 weeks. The tps, idle air control valve, and a few other parts have been replaced or tested and still does it. I do have a surge performance chip on it so that is the only thing I could think off that may be my problem but before I pull it is there anything else I am missing or suggestions.
in the morning when I first start it, it will jump up to around 2200 rpm and fall back down bogging itself out and back up around 2200 and down a few times and will idle high for a while. I know thats not normal and had it at a shop after I messed with it for 2 weeks. The tps, idle air control valve, and a few other parts have been replaced or tested and still does it. I do have a surge performance chip on it so that is the only thing I could think off that may be my problem but before I pull it is there anything else I am missing or suggestions.
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clean your maf, replace your o2's
i dont know much about bronco's, but these ford 5.0's can be moody if they dont have clean/new sensors
i dont know much about bronco's, but these ford 5.0's can be moody if they dont have clean/new sensors
nothing was replaced, everything was cleaned. It is hard to figure out because it will only do it in the morning and not any other time of the day. After that it runs fine without a problem.
No, and no.clean your maf, replace your o2's
i dont know much about bronco's, but these ford 5.0's can be moody if they dont have clean/new sensors
These aren't mustangs.
Read for a little while before you start trying to add information that is wrong.
These trucks didn't go MAF until 1994+, and the O2 sensors have absolutely no input until the motors go into closed loop, which won't happen for at least 5 minutes after he starts it. Also, these trucks, even the MAF trucks, some of them only had 1 HO2S. It wasn't guaranteed that they have two O2's until 1996, when they went OBDII, and you had two plus the downstream sensor.
Motoman, pull the chip. It's near worthless anyway on these trucks. Just bump your base timing a little, and do the sixlitre upgrade.
If it's only doing it cold, you could have an intake air temp (IAT) sensor freakin out your fuel mixture. I don't know if '89 has these, but I think most speed density systems have one.
I agree with the performance chip removal. Get that thing out of there and follow the sixlitre tuneup procedure (search for it here).
Karl
I agree with the performance chip removal. Get that thing out of there and follow the sixlitre tuneup procedure (search for it here).
Karl
The IAT/ACT sensor is mostly used for ignition timing trim and small adjustments in a/f factor, but it won't throw the a/f ratio off enough to cause huge problems. You're probably thinking of the ECT (engine coolant temperature). That's probably the most important sensor, right behind the PIP, your PCM relies on. When it malfunctions, it can make starting in cold weather a nightmare, mileage and power suffer, and it won't always trip a code when faulty.If it's only doing it cold, you could have an intake air temp (IAT) sensor freakin out your fuel mixture. I don't know if '89 has these, but I think most speed density systems have one.
And yes, every EEC-IV Ford I've seen has an ACT somewhere. #5 intake runner or air box on our rigs.
Totally. Chips are one of the first things to go when there are problems.I agree with the performance chip removal. Get that thing out of there and follow the sixlitre tuneup procedure (search for it here).
The tps, idle air control valve, and a few other parts have been replaced or tested and still does it.
Dude, that's confuzzled me to no end. Cleaning the IAC is a temporary fix at best, and there is no cleaning the TPS. Testing and replacement are the only real fixes.nothing was replaced, everything was cleaned.
1 - 7 of 7 Posts
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