Buzzard

I have an 86 Mustang GT with and 87 front clip and a (what i believe is) 87 5.0 HO slight modifications like shorty headers, pro dump exhaut, underdrive pulleys, alum rad/w electric fan, not that theyd have anything to do with my problem. but my issue is, the car just likes to just shut off. no stutters, jumps, or hoo ha's, it just turns off like i was turning the key. Sometimes it will drop in rpms first like its goin to turn off and "catch" itself, regain idle and then just turn off. ive had the car in and out of the garage and they cant seem to fix the problem. they have no idea whats wrong with it. theyve given it back to me saying its fix and everytime its the same thing, sometimes ill drive it for an hour and it'll be fine other times all day but eventually it just shuts off now it just plain wont start(as of this afternoon).if anyone else has this issue or knows what the deal is i'd appreciate any info into the situation. thanks.

ttoppedaerocoupe

do the electronics still work when the car dies, can you just restart it? is it an auto or a 5-spd? notice anything odd before or after it happens (the "like it is going to turn ott but then catches itself again" almost sounds like IAC, but that doesnt make sense after an hour). Now will it turn over but just not fire? kind of sounds like an ignition issue, do you have an aftermarket ignition? Little more details and I am sure someone on here will be able to point you in the right direction.

gbtrout

Does the car just die or does it completely shut off, i.e. dash, headlights lights go off? if it just dies might be a fuel pump problem.

tuff5liter

mine did that come to find out it was the TFI Module thats on the side of the distribuor. I replaced everything in the world before i headed that direction.

Buzzard

ok a little more info. its a 5-speed, and the lights, radio, etc all work when it shuts off, no power brakes or steering and the fuel pump shuts off. theres nothing strange before it shuts off besides when the rpms dive comeback then it shuts off, but it doesnt do that everytime most of the time it just turns off. the car will try and start, its tryin to turn over. no aftermarket ignition, anything that was replaced was replaced stock as far as ignition. it totally seems random, sometimes when i first start it, sometimes after ive been driving it awhile. sometimes it'll start right up other ttimes it wont start at all(like today). damn things possesed.

Buzzard

not exactly sure with everything the garage has done i know they were checking all the grounds, vacum lines and replaced a few things around the distributor.

Buzzard

anyone else have any ideas on whats wrong, this is getting to be extremly frustrating.

Woodard2589

my friend had a problem like this. when he would hit a bump his car would shut off because i believe he said the starter or something like that was loose. have you noticed it happening going over bumps? if its something loose it could be why it shuts off when you start it up, the vibration of the motor could shake it loose again. He also would have problems with it starting back up, sometimes it would other times it wouldnt

fourfivefour

When the problem occurs does the fuel pump run?
I had a car that was jumping spark out of the lower distributor cap and shorting out the ignition keeping the car from starting. Replaced the lower cap the problem was fixed.
You need to figure out what is happening when you are having the problem if it is fuel or ignition related. Check your fuel pressure and check for spark at the plugs when the car dies.

vristang

Have the codes been pulled?
This should be step 1

Exactly, what did the shop do?
This is step 2
It is critical that we know what has been tried already.

Once you know these 2 things you are ready to move on with diagnosing the problem.

Anything else is going to lead to more frustration, as you will be guessing what the problem is.


Good Luck and let us know what you find out,
jason