Danielsmustang

Whatsup guys. Havent been on the forums for a while but I got my stang. Her name os sandy. Shes been sweet but I have been ioing crazy trying to figure her out. So I have been having this small misfire since day one. I bought it and he said it could be a rich misfire. The car had 24lb injectors with a 19lb maf. It only misfired on idle and low throttle. So I went home, changed the plugs. It stayed the same. So I bought a used c&l 80mm maf. It ran like crap. When I fully gas it it goes away. So I said, maybe vacuum leak? Checked and I had one between upper and lower. So I replaced it. It stayed the same. So then I went back to the old maf. It drove better but the same as before. Only on idle and low throttle. Then I bought new wires and ignition coil. Same. New cap and rotor, same. then I put 19lb injectors. Same. Now when I drive it, as it warms up it gets worse. If I fully gas the car it goes away. I just bought a new tfi. As I was installing it, I took out dizzy. Now its out of timing and got to fix it. But I thought maybe, since it has roller rockers, the previous owner didnt tighten them correctly. Could that affect? Or floating valve? What do you guys think? I also cleaned the salt and pepper.

dawson1112

I think valve float would manifest itself at wot or very high rpm .
Have you tried a different dizzy or replacing the pip in side the dizzy? Pretty common for the pip when it starts going bad to cause misfiring.

Danielsmustang

What is the pip inside dizzy?

dawson1112

PIP or Profile Ignition Pickup sensor is responsible for telling the ignition coil to start firing. If the pip is not working at all you will achieve a no start condition , however they have been known to intermittently cause problems creating a miss fire.

This is fords name for crankshaft position sensor and is located inside the distributor.. A complete tear down of the dizzy is required to replace it, most times pple opt to replace the distributor completely rather than just tear it down and replace the pip.

Danielsmustang

Hmm. Okay havent thought of that. Now, how would i be able to diagnose that? Any test i can do to see if it working properly or not? And mind you, it only misfires on idle and low throttle. not under wot. I can be cruising in 4th gear going like 50mph and if i slowly gas it, it will start misfiring, but if i step on it, it misfires for a sec then goes away.

dawson1112

If the pip is working but intermittently cutting out you have no real way to check it, but this page has a lot of very useful tests you can perform NOTE: This test is assuming you have a no start condition.

http://easyautodiagnostics.com/ford_...d_module_1.php

dawson1112

You will have to scroll down a bit to find the pip section

mattdel

That's an EGR misfire. Probably a bit lean, given your conundrum with the inj/maf combo.

Gagestang

Alright, so I start the car up , car idles and runs good, so I drive down the road and shift at 3000rmp and its fine, then if I rev the car over 4000 when I shift the car will start to over heat after about 5 mins after being ran hard and stay hot , it has a 180degree thermostat in it , so to sum it all up, when I run the car hard the car will over heat pretty much immediately

dawson1112

Lol how did you get in this thread