Hello everyone,

Looked long and far with no good answer. XJ won't start up without pumping the gas. It feels like a dead battery with slow cranks( if any) then once I start pumping the gas it cranks faster until it fires up. If I let my foot off the gas she dies. After a couple minutes of sitting on it at 1000rpm she will run fine. Hot it dies half the time. Cold it dies all the time. Checked the battery, cleaned the IAC valve, removed/cleaned the throttle body, and Seafoamed(gas and intake) it with no results. Looking for advice.

224,000 miles 1997

Thanks for reading!

 

I'd check the Throttle Position Sensor.. pumping the gas pedal doesn't do much good on a fuel injected system, but it does change the position of the throttle plate . If the TPS checks out, you might check the Crankshaft position sensor. They sometimes die slowly and can be affected by heat.

 

Check to see what fuel pressure is as as well.

 

The part I'm confused about is how it feels like the battery is dead unless I pump the gas. It runs fine and strong just doesn't start up. Pressure is good just need to check to see if the pressure is bleeding off or not. TPS has good voltage and CPS wouldn't effect how it cranks only how it runs(or doesn't). Still stuck. It isn't a huge deal since I figured out that if I pump the gas it starts, just an inconvenience...

Thanks for the help so far let me know if you have any other ideas!

 

How did "check" the battery? Was it load tested? Because that is indeed how a battery With a dead cell behaves.

IAC could be having problems staying open. You need to check the IAC's pintle movement and test the TPS properly. tjwalker has a great writeup that's been pasted many times on here. Basically the ouput needs to be consistent 0.5 to 4.9 V along the full sweep of the throttle.

 

Try hooking your battery up to a charger or go to autozone and get them to test it for you. They test it while it's in the car, so it's not a big deal for them. I was having slow cranks until I got a new battery. The old battery had been drained a few times when I was diagnosing my dead alternator.

If you have a multimeter, start testing those sensors on the throttle body, like salad said ^^^