start then stall when cold after vacuum leak fixed-HELPQUICK

[AaronB]

I just had the intake man. gasket replaced which fixed a major vacuum leak. No more hissing, coolant leaking, or rough idle, it did wonders. The only problem is now when I start the thing when it is cold, it cranks for a couple seconds, catches and then immediately shuts down. If I keep my foot on the gas for a little bit, it will eventually idle on its own. Once warm, the problem goes away and runs fine.

The mechanic who fixed the vacuum leak said the computer may be recalibrating the mixture since it has had to compensate for a big leak. He scanned it, no codes came back.

Other than the vacuum leak, I have recently changed the fuel filter, plugs and wires, dist. rotor, TPS. I need help ASAP. Any ideas? Thanks in advance for the help.

 

[XJNick]

Hi,

What model year and engine type is this Jeep?
In general, make sure there aren't any disconnected electrical sensors or vacuum lines in that area.
I can't really give any further advice without knowing the model, year, and engine :mrgreen:

-Nick :!:

 

[AaronB]

Yeah, I guess that would help. It's a 94GrandCherokee 5.2L V8. Thanks Nick

 

[XJNick]

Hi,

I don't know a lot about sensors on the V8, but random stalling is often caused by the Crankshaft Position Sensor (CPS).

Since you say it only happens when cold, though, I'd first check the Coolant Temp Sensor (CTS), Manifold absolute pressure sensor (MAP), and Mass air temperature sensor (MAT) for proper operation.

Another thing you may want to look into is if the TPS is adjusted properly, and if the throttle body and Idle air control motor (IAC) passages are clean.

-Nick :!: