Author Topic: 88 mustang stalls in heat (Read 4872 times)

roldy · « **on:** May 22, 2008, 05:02:20 PM »

I have a 8 cylinder 88 gt mustang and a problem that i can't seem to find what the cause is. Every so often whenever it is hot out my car dies. After waiting a good 30-45 minutes, it'll start up. I've read on some forums about the TFI module not working when it gets hot. I relocated it to a place where it gets some air flow instead of it sitting on the hot engine. I have an MSD ignition module with MSD coil. The MSD ignition module is located underneath the dash on the passenger. What could be the problem here?

Soaring · « **Reply #1 on:** May 22, 2008, 06:07:48 PM »

First off, you double posted, so I removed one of them. Not a problem...it happens all the time. On your stalling when she gets hot, it sounds like a classic case of vapor lock. That's when the gas in the line or carb gets so hot that it turns into vapor so won't burn. Since 1988 was the first year for Ford to use fuel injection instead of a carburetor, I don't know what to tell you about keeping heat away from the EFI, but double check your fuel lines to make sure they are not near the exhaust manifolds. The guys with the 5.0's will be along here sooner or later so hang tight.

rmodel65 · « **Reply #2 on:** May 26, 2008, 12:39:31 AM »

you say you relocated the tfi(thick film ignition module) but did you replace it? if not my bet is that it is still bad. they arent to expensive about $45 id put my money on the tfi hands down

roldy · « **Reply #3 on:** June 03, 2008, 06:46:46 PM »

Sorry about the long over due reply. I did replace the tfi with a new one. I took the car to a shop and they said to replace the ignition coil because it was leaking it's oil (I now have a msd blaster 3) and also replaced the tfi (which is now located back on the distributor). Even though I hear my fuel pump working, could it still be causing vapor lock? I looked for pinched lines and sharp bends. Fixed one line but still have a problem. I'll take pics of my engine bay so you can see where the lines are. Also, could old cats be a problem when they get hot?

mike2150 · « **Reply #4 on:** March 09, 2010, 12:24:31 PM »

i have the same prob... identical setup w a '89 fuel-injected TFI ignition w/msd digi-6 msd blaster coil, & msd pro billet distributor... timing advance was 14 degrees... car ran fine for a year... then i put too much oil in it... and had this SAME issue... runs great, but ....

after warming up... it idles rough and stalls at idle (tried adjusting idle speed at TB doesn't stop it from happening...) it also runs very rough after this... almost feeling like running on 6 or 7 cyls, giving a 'bucking bronco' feeling... but at WOT it goes away... (i'd imagine the inertia from the cam and tranny stop any timing or fuel probs.)

where should i begin?? replaced fouled spark plugs... changed oil(so theres not too much) ... have new 02 sensors (maybe they were damaged causing it to run rich/lean)

oil pressure is consistantly HIGHER than usual... used to fluctuate from 30-50... now its more like 45-55PSI and never goes lower...

changed fuel filter last year... doing it again...

all this happened AFTER i added lots of fuel additives (alcohol-based) to pass emissions it CT... AND after i replaced cats w straight pipes (which involved removing 02 sensors)... AND after oil was high...

so 3 variables... where should i start?? vacuum...? fuel? spark?

thx

FASTBACK65GT · « **Reply #5 on:** March 09, 2010, 05:41:15 PM »

You might check your fuel line if it sits close to the intake or other hot parts. It needs to be up and away to get plenty of airflow around it. A good 2" or more above anything hot. Some guys will even run header wrap around the fuel line to keep it from getting hot. It looks like hell, but it works.