How many 3FE'rs with Rough Idle? What are the fixes?

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Well you could pull the computer and check each terminal with a meter before checking it hooked up. At least you would know if the computer itself might be bad. Just a thought? Maybe a little easy on the old back:D.
 
On mine it is usually fouled plugs. I usually have to change them every 6-9 months or so, at least 6, 5, and 2 they seem to foul up faster.

I changed the plugs a little over a month ago and the idle was rough again, so last weekend I had some time to mess with it. Noticed that the air intake attached to the throttle body was not seated right, like someone or something pressed down on rubber intake hose causing the top to tilt up away from the throttle body. Figured I might as well take it off and look in the throttle body while I had it loose. Sprayed some carb cleaner and wiped all the gunk I could with a rag, and put the hose back on tight and seems to have solved that bout of rough idle.

At least until the plugs foul up again.
 
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euclid, air intake tubes are less than 3 months old. Plugs looked great when I pulled the head, almost no corrosion or build up.
 
Ya i know I just read part of the tech section of Toyota trails anyway there was a really good read on 62 fuel injection problem one guy had. If you get the mag. read it;).
 
Not trying to be a smart ass, but have you considered that you may have f-ed up the MAF dicking around with it so much? I know that it is adjustable, but its a pretty delicate peice you know?

Also, what kind of parts did you use for your tune up? 2 year old autozone wires and cheapy plugs could very well be acting like crap by now. Also, did you change the cap and rotor? Could have an excessive gap in there.
 
Not trying to be a smart ass, but have you considered that you may have f-ed up the MAF dicking around with it so much? I know that it is adjustable, but its a pretty delicate peice you know?

Also, what kind of parts did you use for your tune up? 2 year old autozone wires and cheapy plugs could very well be acting like crap by now. Also, did you change the cap and rotor? Could have an excessive gap in there.
I think he bought a new MAF?
 
I have 4 used AFMs, 2 have been opened, two haven't. All of them have the same s***ty idle.

All parts on my cruiser are OEM except for the alternator.
 
I have 4 used AFMs, 2 have been opened, two haven't. All of them have the same s***ty idle.

All parts on my cruiser are OEM except for the alternator.
What about the yellow(my 62 has the yellow color) on the battery for the efi It is tyed in with the fuseable link, red wire for the headlights and white for the alt. I have seen that wire slowly go to crap also?
 
Not turning down your suggestions 88, when I get the opportunity to I'm going to re-check everything, just acknowledging the remark and stating my experience (didn't want my responses to seem jackassish or anything).
 
Not turning down your suggestions 88, when I get the opportunity to I'm going to re-check everything, just acknowledging the remark and stating my experience (didn't want my responses to seem jackassish or anything).
No your good man. I have been following your threads for a year now on this problem and honestly it is bugging the s*** out of me whats wrong. I am normally fairly good with dc stuff but i think i would have to see this one up close and personal.
 
Well, I may want to arrange that sometime soon. It was idling fine before the head problem though, so I'm at a loss. But it does drive me to think it is electrical, and that there is possibly a short somewhere on the PS of the engine. I need to check the plug wires and make sure they are all contacting the plugs properly, but other than that...what could be failing?
 
Well, I may want to arrange that sometime soon. It was idling fine before the head problem though, so I'm at a loss. But it does drive me to think it is electrical, and that there is possibly a short somewhere on the PS of the engine. I need to check the plug wires and make sure they are all contacting the plugs properly, but other than that...what could be failing?
I am 100% sure it is a grounding issue but i would have to see it for myself. I think when you get back sadly you must run a check on the computer to narrow down where the bad or problem circut is at.
 
Tell yea what i will be in Monroe co. in dec. if you dont get the ghost out of it by then i will swing by and give it my best shot. I know its something so simple that you will smack yourself later for:).
 
If you don't already have one, get yourself a timing light and while the engine is idling, hook it up to each of the plug wires for a while in turn and the light will tell you if the stumble is based on a plug not firing (ie that you've got and electrical, not a mixture problem). If you find one is a problem, try pulling the plug wire an holding it close enough the the plug that it arcs across. If the idle smooths out/speeds up you got a fouled plug (which can easily happen if you've messed with the AFM).

HIH,
Bill

--sorry in advance if you've already done this
 
If the test is in the regular FSM, I've got it in the truck in the parking lot 20 minutes away. If it doesn't get solved over thanksgiving, then sure I'd make a trek to let you look at it.

Don't have a timing light, but do have access to one. Plugs aren't fouled, I am running it only as rich as it has to be. Fully desmogging the rig put it where it was running WAY too lean even with the AFM richened 2 clicks, I am now at 5 clicks and could actually go with 6 but economy would start to go down.
 
poor idle

Has anyone checked the condition of the EFI relay and the electrical contacts that the relay plugs into? My 80 series was having the famed EFI relay problem (wont start when hot). I did find that the socket contacts that the relay plugs into were quite loose. I tweeked them to provide a better contact between the relay and the terminal and found that the idle seemed to improve. At least it seemd to. Did nothing for the flakey relay when hot problem though.

HTH...Don
 

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