1999 XJ Sport, I6, etc.

Installed a new alternator after intermittent failures of the old one. Had tons of issues for weeks with the old alternator not fully able to charge the battery and fluctuating between 13 - 13.98 volts while idling. Regardless, pulled it out and it looked like something dug out of a WW 1 bunker. Put the new one in and all seemed well. There was a bit of noise I thought might be coming from the pulley. Before I had a chance to do even consider looking at it as I'm in the first test drive going around the block, the Jeep just decides to die. Battery is very strong, lights don't dim. Strong crank but nothing grabs (crank is definitely turning). Will not start. Has fuel pressure. I can't figure out what's broken other than possibly the new alternator. I'm currently stranded so any ideas would be very appreciated right now.

 

Even if the alternator failed, if the crank and lights are strong, a sudden ignition failure would seem strange. (Unless the battery was very low and the vehicle was running primarily off of alternator output, but then crank and lights would likely be weak).

Given the location of the alternator, double check that the ignition coil right behind it is well connected and not damaged from the alt install.

 

I did check the coil, the distributor, all wires and grounds in the area. Everything appears good. I had started to suspect timing but the engine rocks on it's mounts too much which tells me the crank is turning. It's definitely getting fuel considering I'm wearing some of it now. I'll have to test for spark once I'm able. Side note: the entire ignition system was replaced this summer. Changed the cps as well. It also has a new MAP and idle air sensor. I think the only thing i haven't replaced is fuel rail and injectors. :/

 

MOPAR brand sensors or aftermarket? The general concensus around here is MOPAR or await failure.

 

I"m not entirely sure. I would have to check receipts. It was only a few months ago. that would be a short wait. any sensor or one in particular?

 

Typically CPS on a no start. Have you checked for a spark? And if so, does it look strong and consistent?

 

Well, I'm alone, wet and limited with tools. I've been trying by recording it via phone but it falls over every single time. I don't want to destroy the phone as well. I'm open to suggestions though.

 

Not a great situation to be in.

All I could suggest would be to pull the negative terminal, unplug and replug each of the items you have changed, give it a few minutes and see if it helps. Just keep connectors covered if its raining as you disconnect them and reconnect.

There's not really a great deal I can think of that you could do on the side of the road.

 

Finally found it. Had to get a tow back. Lost light, battery charge, everything. Tested the alternator, cps, etc. Through all of that over analysis, I didn't look closely enough at the fuses in the PDC. Sure enough the one I thought was good wasn't. It was obviously when you turn it a certain way, which I did not do apparently. So new alternator then the fuse blew which I assume is the one that supplies voltage to the ECU (I don't have a diagram on hand). I appreciate the help. Sometimes troubleshooting these things I forget the easy obvious ones. :/

 

Good to hear it turned out to be simple. I didn't even consider fuses.