the car: 1989 LX 5.0 AOD
the problem: it dies if you take your foot off the gas. it wont idle or nuthin.
when you start it, it fires right up, but once you take your foot off the gas, it dies imediately. doesnt stumble - just cuts out.
the problem has gotten worse because it used to idle but the idle was way low - like around 5-600 RPM. it used to run reliably, but you'd have to give it gas for about 3 minutes after a cold start up and it would occasionally die at a stop light. now it dies as soon as you take your foot off the gas no matter how long you give it gas.
it runs great and runs strong, but as soon as you take your foot off the gas - say to make a turn or at a stop light, it dies.
furthermore, i filled the tank
50 miles ago, and it is already
down three eighths (five eighths left in the tank).
the car sat for a year because the trans was down, but it was doing this before, just not to this extent.
i purchased the car in May of '09.
tuned up? yes. new cap and rotor, and wires. new fuel filter. cleaned the throttle body.
replaced Throttle Position Sensor in June of '09. it shoulnt be the TPS, even though the car acts like it has a bad TPS. that helped back in June of 09, but the problem is back, and has gotten worse. and this ultra low gas mileage leads me to believe it is something else or at least something else additionally.
replaced the Idle Air Control
module or whatever yesterday. that did nothing.
put the stock MAF sensor back on (it has a GMS unit). that did nothing.
any help would be appreciated.
btw, i havnt posted here for a while, here is a pic and my mods in case anyone is interested.
1989 Mustang LX Hatchback 5.0
BBK CAI, Pulleys, BBK equal length Shorties, ORHP, Flowmaster Force II cat back, GMS MAF, BBK subframe connectors, 3.55 gears, SSBC brakes-front, SSBC drum to disc conversion - rear, B&M 2000 stall, B&M console Hammer...more to follow.