unknown engine problem

Ok I know I have posted a few times, and my BF and I have figured out the problems with my car before, but this one has us both stumped. We had a problem with an injector bleeding off causing my car in the summer to chug and putter before it would start. So I went out and got the last for freakin OEM ford injectors for that car(took me 3 months for them to find them and close $400 dollars later), well that fixed about a tenth of the problem. They cylender no longer loads up on it but it still chuggs every now and then. We thought well maybe I have a wire going bad. We pulled the wires and they were COOKED, don't buy autolites they suck, It seriously roasted the wires, but my plugs were all normal, so I got Ford Motor Craft wires back on them and motor craft plugs thinking that would solve the problem. Cleaned it up alittle bit. It was pingging so we switched the switch to reg but I'm still running 93 octane in it. Cleaned up the pinging. So the deal is now that when I start the car and its been sitting for atleast 3 hours it fires up first time, it will run alittle rough then start chugging and do this around 200-500 RPMs till it catchs itself..it almost seams like its not firing on all the cylenders..the car shakes, but after about 20 seconds the car itself takes the idle up to about 1500 to 2000rpms and cleans itself up and drops the idle back to around 1k runs fine, except for usually one major miss(as in the car feels like its gonna shut off but catches itself, loses all power for a second then catches itself like it never happened) when I take it out when it's still cold, then once it's warmed up and I start it takes alot of encouragement and giving it gas to make it fire. AND LOL once it's running and warm it has little fluxuations in the idle. Like if I stop at a stop light the idle will bobble ever so slightly. It's got power, it'll still cook tires and boosts just fine. I've replaced every freakin sensor on it, egr, IAC, TPS, my bf thinks maybe my Vane air is messed up..it's the last thing to check. We cleaned the door from sticking, but he's gonna see if he can rip the entire thing apart and clean it all out for a temp fix, cause we are probably gonna convert to mass air this winter. We have run a tester on it and it's not pullin up a single code to even give us an idea. We checked the coil and thinking it wasn't sending enough juice to one of the plugs and its right on the limit as to where it should be. I've replaced the almost every damn thing on the car, and I know its now got 142k on it, but most of the parts are lucky if they have a few thousand on it. I paid 1800 for the car and have put about 4k into it so far and I have quite a few things planned for it before Carlisle next year. You would think the least it could do is run right. If anyone has this problem or knows has to possibly fix my goofed up car I would really appreciate it. LOL or if you can think of something that we didn't think of I mean we are down to either the vane air or the computer is wacked. If you need anymore information about what's wrong with it, I know I don't know as many of the terms I should but I'll do my best to answer or get the answers to help anyone help me. It's been doing this for about 3 months now and I'm just sooooooooo tired of it. Thanks everyone

Hello.. I've been to Altoona before, I'm about an hour away in Cumberland MD.

The IAC and TPS usually are the root of idle problems. Did you unplug the IAC and set the base idle speed to 750 rpm? What about adjusting the TPS to around 0.9 - 0.95 volts at idle? If you haven't, these procedures are outlined in the tech articles.

Also, I had a bad replacement TFI module do something similar to what you're experiencing. It would start right up when the car was cold, then 10 seconds later it wouldn't want to run, the engine would shake and miss terribly, and I had to keep my foot on the gas or else it would stall. It also had NO power, I couldn't go over 10 mph or so. After 30 seconds of that, it would smooth out and run perfectly as if nothing was wrong at all. I drove it for a few days like that, put a new TFI on, and it hasn't acted up since. That's a rather unusual failure mode though, so I wouldn't suspect the TFI just yet.

BTW, slight idle fluctuations and the occasional miss are perfectly normal. They all seem to do that.

Also, your vane air sensor could cause problems like this. Check out the FAQs/tech articles for making sure there are no "dead spots" in the door's travel. You might want to pick up another one at a junkyard. Regarding a MAF conversion, I've never heard of a successful MAF setup on these cars, and there are people here with engines putting out some serious power with the stock vane air setup.

Also have you changed the cap and rotor? These cars have VERY picky ignition systems as you are finding out. [Image: smile.gif]