2002 xj8 base. Car was running great until I came out one morning after it had been sitting about a week had to jump start her and cranking won't start it.
Fuel pressure is 43psi cranking. Give a squirt of ether and she fires right off and runs perfect as long as I don't shut it off. When I do the pattern repeats- crank w/o start (and I believe no injector pulse,) pressure goes up when cranking but won't even spit or burp. Give it a shot of starting fluid on she fires and runs fine. I checked all the fuses under they hood and they're all good. Can feel fuel injection relay "clicking when the key is switched on.

 

btw- no codes, live data reads engine RPMs. Even though I feel the FI relay "clicking" I was going to swap it if I can ever get it out without destroying the harness.

 

Just verified no injector pulse when cranking....when it fires on ether and key is released to "run" injector pulse is normal and car runs perfect.

 

How old is the fuel?

 

You may have a very weak battery. If the voltage is too low the ECU will not enable the injectors.

 

also thought maybe low amps even though it doesn't crank slow...so added the big jump box w/o change..

 

Anyone know if it should start with TPS unplugged? It appears (on live data) to be working but was thinking of the feature that kills injector pulse while cranking at WOT

 

I am out of ideas and ready to punt to the ***********...it just seems that the car is turning the injectors off when the key is in cranking positon but in run they work fine. Compression, spark, TPS, MAF all seem perfect on live data. I have a better generic (Bosch)reader but I think its going to take factory type software

 

Use a smart phone with the Torque app to connect to the vehicle PCM through the OBD port via a Bluetooth interface.

What is the fuel pressure with the ignition in the ON position, without engaging the starter motor?

What is the battery voltage across the terminals when checked with a voltmeter?

The Crankshaft Position Sensor sends a signal to the PCM when the starter engages to energise the fuel injectors. If the CPK is faulty, the PCM shuts down the fuel pump.

 

Just throwing in a thought, in case you run out of other ideas: the inertia switch has been playing up with some other people over the years, and it is controlling / cutting off the FI. Maybe related?

 

Agree with Eric: my first thought was the immobolizer needs to be reset. Cuts of injector pulse to keep car from being stolen or gas from flowing after an accident: sometimes by being bumped in a parking lot.

 

I will check that immobilizer. Thanks!

Fuel pressure is 43 before cranking.

12.5v in the battery. Just to be sure it doesn't drain I have had it on the jump box anytime I crank it.

I'll look into getting that app and OBD plug

I ran it for an extended time yesterday hoping for a CPS code....I assume the ECU gets the cranking rpm's I see on live data from the crank sensor?