Check your Modulator valve.

Mine did it and it was just a tune up and tfi.

The wire harness just behind the bumper under the truck there is a wire that ALWAYS corrodes, or breaks.

You'll need a balljoint press in it is 2 wheel drive but not sure about 4 wheel drive though.

Funny.... When I bought my 86 f150 4.9 from an old lady that let it sit for a while, the same exact thing happened to me with the horrible stench. What the hell is it?

Sorry about that... Didn't notice you already mentioned it.

There is an inline fuse right behind the battery in the wire harness. Check it. The inline fuse will make the alternator not charge the battery if it blows, but if it is getting corroded it will slowly charge the battery, but not allow enough juice to keep it running on the alternator alone...

Well, I adjusted the IAC about 3/4 of a turn out and it is idleing great, and it's no longer stalling when I put it into gear. It seems that the new carb had to be adjusted to my engine. Thanks to you all for the great help, and god bless!

Fellro that is what the carb is doing, so I guess it is correct. The IAC is something that when I replaced the carb it did not come with a new one. I fealt it moving the throttle when the engine was starting to stall. The truck runs really good once warmed up, it just does not seem to have any...

Just as a side not though.... with the anti stall dashpot.... I closed the choke plate a little bit, I mean really little bit, and the idle straightened out great. I went a little further and it roughened up. But there is no adjustment so I don't know what I could do to change it.

I tried taking the dashpot out of the equation, but it just died. I took off the IAC and adjusted the stop screw 3/4 of a turn, and the idle is up a little. I won't really know if it fixed it until morning when it is cold again, but I will keep you guys informed. The little anti dust grommet was...

Awesome, thanks Amkatt. I probably have to adjust it by bending the rod that links it to the choke. It is bent, which seems unnecessary to me, so I was thinking it might be an adjustment. Otherwise why would the link not be just straight?

B.T.W Doug.... Love that truck in your profile pic!

So if it can be eliminated, then I will unhook the vacuum line and see if that makes any difference. I will let you guys know what happens. Thanks to you both for your replies by the way. I have been on other ford truck forums and there is nobody that post any answers except this one guy who...

My choke pull off is only a year old. I bought a rebuilt carb from national carburetors about a year ago, and it was part of it. But I don't know if mine is adjustable. I know that there is no screw on it. The only possibility would be to bend the arm connected from it to the choke. My choke has...

Fatherdoug please don't think I'm dumb but is that the solenoid that moves the throttle when it is about to stall, that is mounted on the carb behind the throttle? If so, then no I did not replace that and I am not sure if it works, or how to test it. Rock auto has it listed as a idle air...

I have a 1986 F-150 2wd with a 4.9 automatic c6 transmission, and the feedback carb system. For the past several months I am having rough idle issues when the truck is starting cold, or cooled down. When I put the truck into reverse, or drive for the first time after cold starts, it wants to...

Well I screwed up. I took the carb off today to try to see if I had the adjustments correct and upon bolting it back together, I stripped a bolt. Now gas is pouring out of the bowl vent, and leaking out of the upper gasket so I guess its time to buy a new carb from rock auto. It seems the carb...

The IAC also was not showing any voltage with the key on engine not running. Is this normal?

I was testing the tps and no matter how I put the wires for testing it is staying at 5 volts. No changes when I open the throttle. I am thinking that means it is bad, but also I was wondering what the PIP means. Does anyone know?

I do have a digital meter. I was going to try testing it today. I was looking under the cap and rotor yesterday, and there was a small broken piece of metal in there. I replaced the cap, rotor, and coil, and it did not help. I really looked because of the (pip) code. See a long time ago I was...

yeah I agree I think I will order a tps thank you for responding so quickly and god bless

bump bump bump bump

ok so I ran the test, and I got the following codes. Engine off, Key on 23, 10, 14, 51, 63, 13. 23 TPS out of range 10 Nothing 14 Ignition Profile Pickup (PIP) circuit Failure 51 ECT Sensor out of range 63 TPS Circuit fail 13 RPM Idle out of range idle to lowJust want to say I have ran the...

Yeah unfortunately I don't have a test light, or analog meter. I have a digital, and I did the hook up, but I was unable to decipher the flashes that way. So I found a pretty nice reader on amazon INNOVA 3145 Ford Digital Code Reader for this truck for just over $25 and it is arriving today. I...

I truly appreciate the ideas. It has been a while since I looked at this post because nobody has responded to it in a while, but I found out that I have OBD1 on this truck which I was unaware of. I ordered a scan tool for it which will be here tomorrow and I am going to scan for the codes, and...

I unscrewed them and soaked them then reinstalled them. I don't remember if there was 2 or one. I think just one. Also the idle tube. Its a Carter YFA 1bbl

Thank you for the advise. I did set the mixture and it still is doing the same thing. Thing is, I don't know where to look. The gasket under the egr spacer probably should be changed, but there is a big tube running from it to the exhaust and I cannot seem to break it loose so I can lift the...

bump bumpbump bumpbump bump

I also have very little power going up hills. I had it floored and only hit 35 going up a moderately steep hill. About 35 degree angle or so. But for some reason it also was not kicking down to second gear, so this was in 3rd gear. Please someone help.