Just got a 2002 XJ8 4.0 Motor will turn over (Slowly) but will not start. Two weeks later I got another one and it has the exact same problem. I want to get them both on the road. What could possibly be the common problem. I am hopeful it is not the fuel pump because neither will crank even if fuel is poured in the throttle body.

Can anyone help me trouble shoot both to find answers?

What is the best OBD2 scanner for them?

 

I've moved your question from General Tech Help to X308 forum. This is the place to post technical questions about the XJ8.

Graham

 

OBDII Recommended are the ELM 327 units, along with the Torque app if you use a smart phone.
I suggest downloading an electrical guide (in the stickies) for your model year - it helps no end.

 

I use an iCarSoft 930, works well for mine. Did you use the same starter motor with each engine you tried? Seems to me that the only common denominators between 2 different engines are the starter and the wiring systems to it? There's a lot on here about the affects of bad earthing cables, did all the earths go back on clean and tight?

Paul

 

Starter is probably not getting enough voltage. Check your battery, then check the voltage your starter is getting. If your battery is good and just not charging, then it could be wiring issues or your alternator.