Recently my 1990 F-150 started having idle issues, especially when coming to a stop in Drive. It got to the point to where it would actually die at stop signs. I eventually figured out that the MAP Sensor had gone bad, so I replaced it. I continued to have idle issues and the truck would still die when coming to a stop. I gave it a few days for the ECM to relearn how to idle correctly, still the same issue. I took it out on the highway and drove it at 60-65 m.p.h., and when I next stopped it was perfect. The point of this thread is to let folks know that it is apparently necessary to drive the truck at highway speeds for the required 10-15 miles for the ECM to reset the idle correctly. I hope this helps someone out.

 

It sounds like your truck had the same problem my 92 has. I thought about replacing my map sensor today but at 60.00 I have to wait. The guy at Orielly's said it could also be the coil. Well the coil is cheaper, so Idecided to try that first.
My truck seems to not die as often when it's cool or the engine's not real hot yet, was yours that way too?
I may have other questi.ns for ya, so please bear with me, My truck has been having this problem for at least a year, I've had the truck to several shops,and spent several hundreds of dollars, and everytime ithink it's fixed, it goes and starts the same old crap again.
Apparently no shop around here at least knws what the hell they are doing, except guess, throw parts at it, and rip me off.

 

I went through a few things before I discovered it was the MAP sensor. I cleaned both the IAC and the EGR, which can be causes of this problem too. This didn't fix the issue, so I disconnected the MAP, and the idle stayed the same, so I went and bought a new MAP sensor at that point. I got mine from Rockauto for $35.79. It is made by Standard Motor Products, and was made in the U.S.A.! Anyways when i put it on at first like I posted, no change. What I had learned from research is that for the ECM to reset, or relearn the idle and other functions, you had to drive it 10-15 miles after reconnecting the negative battery cable. Well, just driving it around FT Bliss wasn't enough. I ran it down the highway, the ECM reset, and she purrs once again. I did notice that the truck was worse about dying once it warmed up, probably because the idle was still higher from just being started. If I were you I would definitely look at the MAP as a probable cause for your idle/stalling problems.

As far as the problem being the coil, if yours acts like mine did, with the surging idle then stalling, I do not believe it would be the coil. A bad coil can cause misfiring and rough idle, but eventually it would get to the point where the truck would not run. I would expect this would have happened after a year of running poorly. I never trust the counter guys at parts stores, I may be being arrogant, but if they were good mechanics, why do they work at a parts store?

My truck did worse when it was warm, probably because when it is first started, they are still in high idle/cold running mode so they are less likely to die. When I would start to come to a stop, The truck would surge between 2-300 rpm and 1000-1200 rpm three or four times, then die. If you are experiencing the same issues, chances are good that your MAP Sensor is not functioning correctly. If you are on a budget as I am, remove and check your IAC and EGR for excessive carbon before going to more expense. It may be something as simple as that. Also check these parts for proper function as well. I hope this helps, feel free to ask anything. I am honest, and if I don't know the answer, I will say so!

 

I installed a new IAC, the 3 major compoents of the egr system, new temp sensor, 2 new TPSs and the fuel system professinally cleaned all of these were recommended by the various shops I took it to. One plce did "find that the rubber in my harmonic balancer was ripped and it was seperated. altho, I checked all the pullies and I didn't see that the balancer was pulled forward against the crank pulley.
If it was in fact seperated it had to have been caused by the shop that changed my timing set when they replaced the water pump. apparently they broke a bolt and had to drill it out, so they changed the timing set without asking me while they had it all apart.
I also installed new plugs wires, cap rotor fixed several broken vacuum lines. If there are anymore vacuum leaks, I sure can't find them.

Does rockauto take paypal?

 

Sounds like you have been through the wringer with yours. The MAP sensor was the fix for mine, I had issues finding the problem as well as I described. Once I did, and got the ECM to reset, Mine runs wonderfully. I read this article, and it seems like it is accurate on how to test your MAP sensor:

How to Test the MAP Sensor in a Ford Bronco | eHow

Give this process a try and see what results you get. Also I do not know if Rockauto takes Paypal, I always just pay with my credit card.