I just registered to get help with this problem.

I just finished putting a newly rebuilt engine in a 1992 F150. It is a 302 (5.0) and it runs great, at least when it is NOT idling.

When you first start the truck it runs great for about 30 seconds or so, and then the “surging” begins. It will idle up and down constantly and start choking itself. One the surging starts, it will black smoke out of the exhaust. The truck can be driven and then parked back to let idle and it will start it all over again. You can shut it off, and then start it back (with the engine still hot) and for 30 seconds it will be fine…then it will start surging again. So being hot or cold seems to make no difference.

I’ve scanned the truck and have had no success finding any fault codes. I cleaned the throttle body and various components on it (throttle position sensor and the idle compensator). I even put a new MAP sensor on it with no luck.

This is NOT the first engine I have put into a Ford like this. Just last week I did a 1995 F150, identical to the 1992, and had no problems whatsoever with it, and now this happens.

Any information will be greatly appreciated!

(and this is why I prefer Chevy’s!!!!!!!!)

 

bump to start this....

 

hey my truck does this to im thinking its a bad wire somewhere on one off the secors or throutle body..hope to here more???

 

bump...........

 

Try checking the Idle Air Ctrl Valve, its on the throttle body. Its shaped like a tube and has a sensor on it. Take it off, remove the sensor(VERY IMPORTANT) and clean the valve itself. It has a plunger and is kinda like a needle valve, it ctrls the amt of air at idle. If it is dirty and scummy the idle will be screwy. Do not get any cleaner in the valve position sensor, It could screw it up. If the cleaning dont work, ck the sensor. I had the same prob on my 92, cleaning the valve made a great change in the idle.

 

I think I figured out what the problem is...the number 2 plug had water on it so I pulled the head (thinking it was a blown gasket or cracked head). Turned out the #2 cylinder had a small pin hole in it allowing water into the cylinder.

Needless to say I had to pull the motor out again.

Damn fords!!! This is the LAST ford I will ever overhaul.

Another thing, the only good thing a ford has is the ability to completely remove the wiring harness, other than that I ****in hate fords.
just thought i'd share

 

This is the wrong place to go bad mouthing Fords...

on top of all that, it doesn't even sound like the problem is related to the thing even being a Ford.

 

True...could have happened to anything. But being as I just registered here and it's all about Fords, seemed like a good place to "vent" my anger.

Anyway...great forum guys, it seemed like a lot of the tips I read for similiar problems were exactly what I have already tried, so it seems like everyone here knows what they're talking about. Could be because you have so much experience working on your Fords (had to throw that in there!).

 

People here are very knowledgeable and for the most part well mannered. I could probably spend just as much time reading on a Chevy forum, too. Just had to throw that in there.

 

bump...any other suggestions??? I still have a "surging" problem!!! I cleaned the IAC, the throttle body and have checked all vacuum connections. I replaced the 02 sensor, knock sensor, map sensor and checked teh fuel pressure (seems like it was around 35).

What else is there?

 

Try the simple stuff, fuel filter, also check to see that your fuel lines are not stopped up with crap.

I had an '84 F-150 that had sat for 3 years when we got it. Put fresh gas in it and jumper cables and she fired right up, no problems whatsoever, until the sludge in the gas tank got in the lines and stopped it up and it wouldn't run worth a darn. Had to flush the lines twice and put a new tank on but that fixed it and that truck was driven from here to Baltimore the next week with no problems.

Actually your problem sounds like the problem we're having on our Silverado, except in my opinion it has a bunch of vacuum leaks that we can't find.

I feel just like you with that truck, that's why I hate working on Chevys, almost impossible to figure them out with out a rocket scientist beside me.