Hi fellas,
I got a problem that maybe one of you might have some insight on. It started a couple of weeks ago when I think I got some bad gas. A few days after putting said gas in my truck ('94 5.0w/auto) it started idling really high, probibly around 2000- 2500rpm (no tach) and wouldn't settle down for a long time. Even once it did it was still pretty high. But no "check engine" light. So I ran most of the gas out of it, which was easy because the mpg has went to crap since this condition started, re-filled with good gas and added some Iso-HEET and inj. cleaner for good measure.
No better
So I figured maybe the O2 sensor got messed up by the bad gas, and it was old anyway so I replaced that. After that it would eventually idle down and seemed ok. Notice I said seemed.
Anyway I got the truck packed up for deer huntin last weekend, right away the truck felt good if not better than before. Once I got on the highway it was a differant story. Now the check engine light comes on and off and the truck hesitates and stumbles bad. The only time it feels right is when you floor it, and even then it takes a few seconds to kick down. Rapping the gas seemed to help, and was the only way I was able to limp home. The truck will idle just fine now, but then something happens and it will idle so rough it almost dies, then usually pops back to life.
I tried code scanning it but my scanner is on the fritz so I was only able to do a KOEO test once and it came up 111 (no codes) on both the current an continuous memories. I don't understand that either seeing as the check engine light did go on and off a bunch of times.
Anyways I will hopefully get a good scanner tomarrow, buut anyone have any thoughts for now?
Worst part of this story I had to drive my buddies Buick to go huntin'. Man, I hope noone saw me!!

 

Hello!!!????

 

Well I had the computer scammed by a parts store and their fancy schmancy reader was unable to read any code too. I guess my scanner doesn't have any problems it is the computer on the truck.
Anyone have any idea as to why the computer won't send it's codes? With my reader it will only read a portion of the code and then it quits. Sometimes it won't read at all.

 

Like I stated in my other post, pull the codes yourself. Visit www.fordfuelinjection.com and it will tell you how to do it yourself. All you need is a jumper wire and a pad of paper.

My personal opinion is probably a failing throttle position sensor, failing IAC valve, and or the fuel pressure regulator.

I also have a feeling it might be a bad computer. See if you can swap one in from a buddies truck or somethin.

 

Thats what I amthinking it is too. My brother said he was able to have his computer "reflashed" on his Dodge. Is this possible on the Ford system?

 

Are their any performance ECU's out their?

 

Now that i dont know. I do know that the newer super dutys were able to get flashed due to a problem with their diesels, but I'm not sure about these trucks.

Main thing is, don't freak out. Whenever somethin goes wrong with a vehicle people automatically think its the computer and replace it and guess what? Problem is still there. Start with the basic things and move your way up.

 

I broke down and brought it to a mech. He seems to think it is the mass air flow sensor. My question to him was, why would my computer only send half of a code sequence or none at all? He didn't have a very good explination but he was going to try swappin it out in the morning with a good one and see what happens. I still think it is computer related.
Another question I have was if it is possible to put a computer out of a Lightning in for performance gains? This might be a stupid question, but I thought I heard once that you could do this with Mustangs to up your hp.

 

I am 99% sure it is your TPS. I had the same problem and the TPS was bad.

 

I just experienced this on my pops 87 F150 5.0 high idle and stubble when placed into gear no codes on the computer... Turned out he had a dead spot in the tps and the ECT was not reading correct temp thus placing the system into cold start loop..A bad MAF sensor would throw a code out replaced both the ECT and the TPS and problem solved

 

Well the problem has been solved, but I won't be able to tell ya what it was until tommorow. The reason i wasn't able to retrieve codes was due to a bad wire on the test connector. The mechanic wasn't 100% that he figured out the problem and I needed the truck for huntin so he told me to drive it for the weekend, check it out, then come back on Mon. square up on the bill and he would tell me what was wrong. So I'll let yaas know tomorrow... ... or maybe I'll skip paying the bill and just wonder as to what it was. Only Kidding