My 97 Grand Marquis dies when running or idle. Happens with warm or cold weather. Just change the gas pump for a brand new one, the gas presure got from 38 to 43, felt better for one week only since pump installation.

Now the car feels the same before pump change (heavy and no powerful). It still has the same nasty problem...it dies anytimes.

Need help...it's driving me crazy.

Cumputer monitors says all sensors are ok. Disconnected the original alarm system and the custom Clifford immobilizer: does the same.

Could be a bad IAC, computer ???

Any ideas?

Thx

Most likely your problem is your IAC valve. These will cause sputtering, sluggish idle, extremely high idle when first starting up, and also could cause the car to die after being cranked. You can get IACs a lot cheaper than you used to...less than $80 bucks all day long at NAPA.

But just for kicks, disconnect your positive battery cable first for about 20 minutes or so to allow the computer to reset itself. I've seen it cure everything from check engine lights to rough running.

Good luck!

Could IAC stop the engine while running too??

YES.

If you are hearing a "hooting" sound or if the only way you can keep the engine running is to step on the accelerator AT IDLE, it's probably the IAC.

Something else it could be and this is a cheaper fix. There is a fuel pressure regulator on the fuel rail, single vacuum hose to the top. I'd replace that first unless YOU ARE experiencing the above symptoms for a bad IAC.

Best wishes.

Interesting!

Something I forgot to mention is that when it dies, I can't start the engine again instantly, sometimes 1 to 5 minutes later it starts as nothing really happend.

IAC

Thank you!!!