Stalling on hot days

[helrazr]

I recently bought a 1988 Mustang coupe with 155,000 kms on it and on hot days sitting at a traffic light it will start to run rough and then stall. Attempting to restart it doesn't work for a few times but after a few minutes it will start and work fine for a few minutes then I get the same problem. The temperature guage reads below the halfway point and the fuel pump always works (audibly) when attempting to restart. I haven't had chance to check the TPS setting or the timing or anything but I believe It's either the coil getting too hot or vapour lock in the fuel lines. Any help is appreciated.

 

[Michael Yount]

Vapor lock is unlikely with an efi car - the system is running up around 40 psig - hard to vaporize it with that much pressure (one of the benefits to always placing a fuel pump at the REAR of the system near the tank by the way).

I'd start by pulling the diagnostic codes out of the computer. WalMart sells code readers for about $30US and the port is part of the wiring harness behind the driver's side strut tower.

 

[stangbear427]

I wouldn't trust the stock gauge either- they are notorious for being radically in-acurate. My wife's gauge never goes past half way either, but that didn't stop it from over heating. Your well over the 100K mark, invest in some good gauges like Autometers and don't get taken by surprise. Good luck

 

[AUBURN1111]

I had the exact same thing happen and it got worse and worse until I had to get it towed, turned out to be computer that was on its way out.