G-Funk

So I am having some issues with my 2000 XJ. It is hard to get started up. Usually takes a couple key turns to fire up. Once started it drives fine...until I turn on the AC. Then it dies and won't fire up again unless it sits for a little while. Is that the crankshaft position sensor? MAP sensor?

bender32

The symptoms do not match a bad cps... I would rule that out

G-Funk

Now I can't get it started at all. Checked the fuel pressure and it was good. Battery is new and was good. It tries to crank over but it just doesn't. Any thoughts?

foreveryoung001

What is the fuel pressure? Are you getting spark? Have you done any other trouble shooting?

G-Funk

Fuel pressure was around 45. Those are the only test I have done. Don't know what else to do.

foreveryoung001

Next thing I would check, is if you have spark. There's a bunch of detailed write ups on how to do it, so you can just search the forum or google or something, but basically you want to take one of the plug wires off one of the plugs, stick something metal in there... I use a screw driver... then have someone crank the engine while the screw driver is sitting close to the block, and see if you have a strong, snappy, blue spark.

If you have a spark but it not strong, that could keep it from starting. Not having spark would certainly keep it from starting.

If you have good fuel pressure and good spark, then next I would check compression.

TheGreatGazoo

When you say "It tries to crank over but it just doesn't." you mean it cranks over slowly? not at all? or cranks over fast but doesn't fire up.

tjwalker

Any check engine light? If so, you must retrieve codes for guidance.

G-Funk

It cranks over normal like it did when it ran perfect. I don't know if that is fast or slow. There is no check engine light on. I read some tests on checking the spark on Jeeps without coil packs, but I haven't seen anything for a 2000 or 2001.
Thanks for your help!

TheGreatGazoo

Then I would get a can of starting fluid remove the air filter hose going into the throttle body, spray a 2-3 second blast directly into the throttle body put the hose back on and see if it fires up for a few seconds. this determines if it is a ignition problem or fuel problem.


I will have to say, you are having the Exact same problem as I did when my CPS went bad. it started every time when cold but it had to crank over a few times before it would start . this went on for a week or so then one morning it just would not fire up anymore. I replaced the CPS and no more problems

G-Funk

I will try the spray to help eliminate that. I just want to figure this out. It would suck to have it towed to a shop. Thanks again! If anyone thinks of anything else let me know. Kinda desperate here.