Idling & Dying

[pekin22]

When I start my 93'automatic (when engine is cold), the rpms rise to about 1500 for about 20secs. then settle down to under 1000. When I put it in gear it wants to die. If it dies and I start it again it runs fine. Any ideas?

 

[Vazcular]

Originally posted by pekin22:
When I start my 93'automatic (when engine is cold), the rpms rise to about 1500 for about 20secs. then settle down to under 1000. When I put it in gear it wants to die. If it dies and I start it again it runs fine. Any ideas?

Sounds very similar to my 94 ATX bro. I'm still trying to figure it out after four years of the same problem!

 

[sdpatt]

You may want to try to reset the idle range program settings. Disconnect the battery and leave the headlight switch ON for 15 minutes to drain RAM from EEC. Turn off headlight switch, reconnect the battery and start the engine. Allow the idle to settle down to near 1000 rpms. Within 70 seconds from the start, engage all loads that the engine will seeat idle: Transmission in DRIVE, A/C to AUTO, Headlights ON, turn steering wheel from side to side, press brake pedal.

It sounds as if your idle air control (IAC aka IAB for idle air bypass) valve is not moving enough to allow the engine to carry the extra load of the torque converter. If the memory reset does not correct it, you may have to remove and clean the IAC valve.


------------------
Scott

1991, 253K miles, glass hood, police grill, SVO shifter, Catz fogs,
K&N, 73mm MAF, Superchip, PP Y-pipe, Borla cat-back, 190 lph pump
Eibach/Tokico/polyurethane, SHO Shop front & rear strut braces,
16x7.5" Moda R1, 225/55ZR16 Bridgestone RE730, -1 deg camber x 4,
Class II hitch, Silver award at the SHOklahoma Car Show

 

[pekin22]

Thanks for the help sdpatt! It runs great now, do you have any idea how the idling could have gotten messed up? Vazcular you should try this, it may help.

Originally posted by pekin22:
When I start my 93'automatic (when engine is cold), the rpms rise to about 1500 for about 20secs. then settle down to under 1000. When I put it in gear it wants to die. If it dies and I start it again it runs fine. Any ideas?

 

[sdpatt]

The idle program settings are stored in RAM which means that each time the battery is disconnected the settings are lost.

Scott

 

[pekin22]

I'm still having idling problems. The first time I reset the RAM my car it ran great. I had to disconnect the battery about a week later, and now after trying to reset it about 3 or 4 times it's back to the same problem. I installed a new IAB about a year ago, I removed it last night and it was very clean. I sprayed it down anyway with C&C cleaner, but it didn't seem to make much difference this morning when I started it. How much travel should the piston in the IAB have? Mine moves about 1/8". Any ideas?

Thanks,
Chad

Originally posted by sdpatt:
The idle program settings are stored in RAM which means that each time the battery is disconnected the settings are lost.

Scott

 

[sdpatt]

When you reset the idle settings the later times, did you also apply the loads to the engine within 70 seconds after starting (shifter in "D", A/C ON, lights ON, turn wheel side to side)? If it worked properly the first time and not later times, it sounds like something different in the procedure.

Scott

 

[pekin22]

I'm trying to do the same procedure. The only thing I can't remember is if the rpms dropped to about 1000 before I applied the loads; when it worked the first time. Now the rpms set at about 1500 and don't drop.

Originally posted by sdpatt:
When you reset the idle settings the later times, did you also apply the loads to the engine within 70 seconds after starting (shifter in "D", A/C ON, lights ON, turn wheel side to side)? If it worked properly the first time and not later times, it sounds like something different in the procedure.

Scott

 

[High Plains Drifter]

Does the car have to be up to temp to reset the computer? ie...thermostat is open? If not, why not just leave the battery cable off with the lights on overnight, then you'll for sure know the computer is drained.