Fluctuating idle and shutting off

Hi,

Do you mean the battery is too weak to start it requiring a jump start? Or, is the starter working properly and the engine won't run and ends up draining the battery?

If it is a crank no start condition, take a look through this link and see if anything helps:

https://www.2carpros.com/articles/car-cranks-but-wont-start

If it is something different, let me know. Also, feel free to ask questions you may have.

Take care,
Joe

Hi,

Based on which engine you have, it could be low. Here are the specifications based on the vehicle's VIN number (serial number). These pressure indicate an engine code by a letter (U, T, V, or Z). If you look at the VIN number on the vehicle, the 8th digit from the left is the engine code. Check that and compare it to this info

2002 Cadillac Truck Escalade V8-5.3L VIN T
Fuel Pump Pressure
Vehicle Power-train Management Fuel Delivery and Air Induction Fuel Pump Fuel Pressure Specifications Pressure, Vacuum and Temperature Fuel Pump Pressure
FUEL PUMP PRESSURE
Measure with the Key On Engine Off with the fuel pump commanded ON.

Vin (V,T,U)
Fuel Pressure (gasoline) .................... 55-62 psi

Vin (Z)
Fuel Pressure (ethanol) .................... 48-54 psi

________________________________

Based on your description with the idle, it could be something as simple as a vacuum leak or idle air control valve (IAC). The IAC is responsible for maintaining the engine's idle speed. A vacuum leak can also affect the idle and vehicle drivability.

Here is a link that explains how to check for a vacuum leak. Check this.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Also, let me know if the check engine light is on when the engine runs and if you had the computer scanned.

Take care and let me know if you have other questions.

Take care,
Joe