Bad maf

 

Look for a vacuum leak.

 

Nice looking ride!

maybe some of the coolant somehow got on the mass air meter sensor and is distorting the measured airflow... have you tried cleaning it.

could just be coincidental timing and your tuning chip crapped out

 

Mass Air

 

If it runs in limp mode with the maf unplugged, that's pretty much your answer right there. Doesn't take much to contaminate a maf sensor. Try spraying it clean with maf cleaner.

 

The intercooler piping/MAF is routed thru the fenderwells so its pretty well hidden. I did purchase a used BA2400 from a local (same MAF as I currently run), bolted it up and had the exact same result when I fired it up. The symptoms it has, it acts as if its a huge vacuum leak. I've gone over every line twice and found nothing.

 

Did you have to unplug/disconnect anything else while working the t'stat gasket? Distributor harness? If you hosed off excess coolant -- did you get the distributor/harness/sparkplug wires/boots (dizzy end) wet? Might want to dry all that out. With a fender well mounted maf, I'm having a hard time believing this is related to the mass air sensor.

If it ran fine before you sprayed water under the hood - the odds are that something got wet that doesn't like being wet.

 

After trying out the other MAF, I've pretty much ruled out that its the culprit. Like I've said before, the car fires up on a quick turn of the key, runs for about 1 full second then cuts out like I turn it back off?? If I try to feather the throttle to keep it running it boggs/sputters and eventually dies out. Could a bad TFI module cause this?

 

Anything is possible - but the typical failed TFI usually shows up with high temps. Car starts cold/drives fine and after 15 minutes or so - once everything warms up - it will die at idle or miss/break up under heavier throttle, etc.

Back to my question -- how liberal were you with your water hose? I'd go through looking to dry out connections, etc. They sell a 'drying' spray - I'd pick up a can and break down every connection that might've gotten wet (dizzy too) and see if you can be sure that everything is dry.

 

When the car was running, it had a similar issue after short drives. I'd go up to the corner store, come out and the car was dead. Give it a few minutes and it would fire up and drive as normal. Maybe a sign the TFI was on the way out? At the time I thought it was a bad ground as it would do it randomly. Also, the TFI is close to the thermostat neck and I could of got it wet and smoked it for good? I did pull the connector and spray electronics cleaner which did nothing. I hate to keep throwing parts at it in hopes I magically find the problem. Last resort will be taking back up to the tuner$$.

 

Normally when a TFI goes bad, it goes bad and thats it and doesnt work anymore. They normally dont go in and out.

 

I've had tfi modules act all sorts of ways when they were bad (or going bad).

One time I had one that would start sputtering when the engine wasn't fully warm and gradually have the rpm band in which the break-up happened shift upwards as it warmed up, then finally would run perfect once the engine was up to temp.

Another one would make the engine hard to start, but once warmed up would run perfect. The way I diagnosed that one was by pulling the warmed up tfi off the car and putting it in the freezer, then back on the car and have the hard starting return.

Most of the other bad tfi modules would make the engine cut out or break up when they warmed up.

 

I thought I read somewhere that they progressivly show symptoms of going out? I'll try and get a video uploaded this weekend.

 

just a thaught if u have a spare coil around throw it in. also put ur hand on the coil if its hot when it running fien like extremely hot it may be your coil i had a similar problem

 

added to the list. Thanks!

 

"Normally when a TFI goes bad, it goes bad and thats it and doesnt work anymore. They normally dont go in and out." If you use the word "normally" like I do --- then this statement isn't true. They do all sorts of crazy things when they go bad. That's why they're hard to diagnose. Mine came and went randomly and not acting bad very often for 6 months before I figured it out.

To the OP - the operating guts of the TFI are sealed in a gel-like substance. I doubt water could do any harm there -- although the electrical connections could be compromised, and water could get inside the distributor where the connection between the TFI and the dizzy is made.

If you were having those symptoms before -- sounds like it might be TFI time for you. Consider relocating it -- it was a poor choice by Ford putting it on the dizzy. They relocated it on everything else (including later Mustangs) and had to settle class action lawsuits over it.

 

Cool, sorry guys wasnt trying to pass along any bad info. Ive always been told when they go out they go out. To the OP, I had a 93 Cobra that acted somewhere along those lines and checked the fuel pressure and was only getting about 5psi. Fuel pump ended up going bad. Also have you thought about the PIP sensor?

 

So a gentlemen from the local car forums stopped by yesterday to take a look at a car that I have for sale. Turned out to be a pretty big Mustang guy so after talking for a few I told him about the issue I'm having and he immediately said it was the Secondary Fuel Pump Relay located in the P/S kick panel above the computer. I've replaced the relay under the seat but never knew about one in the kick panel above the computer. Can anyone verify that their is in fact another fuel pump relay in that location?

 

I had a run condition just like yours with a 92 . It would not idle with the mass air conected and if you pedaled it it would pop and miss fire in the intake . Tried everything from mass air to computor . Pulled a vac line and it ran better but still crappy . Turned out to be an injector problem . I think one or more were stuck open . When the mass air was pulled the limp mode would let it lean a bit an run . It might not be the problem but something else to look at .

 

Snapped a quick video to show what is going on..

 

Pull the two big connectors apart on the main harness at the firewall (aka salt + pepper shakers... boy do I dislike that description). Spray them out liberally with some good contact cleaner and take a close look at the pins on both sides. I like to use the Caig Deoxit DN5 spray cleaner - don't use WD40, as it doesn't have the deoxidizing capabiity and is basically just paraffin suspended in mineral solvent. You can use the radio shack stuff as an alternative.