jordan96xj

Typically, the best way is to upload the video to youtube then post a link to it here.

Brian Day

Awesome here is the video so you can better see what I'm dealing by with.

jordan96xj

That has the hallmarks of a major electrical failure. I would start by thoroughly cleaning and inspecting every major connection and ground location under your hood. Not taking any for granted. I would then search the major harness portions for any type of chaffing against metal brackets and such. I would also do a harness shake test in the driveway at idle to see if I could get the engine to cut out while wiggling the harness.

Particularly inspect the main cable from the battery positive to the PDC (fuse box under the hood).

Here is some visual information on the ground locations:

Brian Day

[QUOTE=jordan96xj;3423558]That has the hallmarks of a major electrical failure. I would start by thoroughly cleaning and inspecting every major connection and ground location under your hood. Not taking any for granted. I would then search the major harness portions for any type of chaffing against metal brackets and such. I would also do a harness shake test in the driveway at idle to see if I could get the engine to cut out while wiggling the harness.

Particularly inspect the main cable from the battery positive to the PDC (fuse box under the hood).

Thank very much! That video is extremely helpful I didn't know about a couple of those grounds, I'll definitely pull them off and check them out I seriously hope this is the end of my issues...

Brian Day

After spending most of the morning meticulously gowing over all the grounds in the previously posted video and double checking all of the plugs I could find. My jeep seems to be running a lot smoother at idle, the throttle response even seems better this may be my imagination though lol however I just drove it on the freeway about 7-8 exits and she was running like a top, I stopped on the off ramp to turn around and head home happy as can be because I figured my issue was gone when it just flat out dies... won't fire for the first 3-4 attempts to restart then on the 5th crank I held it a bit longer and she started to spit and sputter as if it was trying to fire then finally the 6 crank she's alive and running smooth I got it back home with out a hitch. Turn it off and same thing hard to start... could it be the ground cleaning was only one of my issues could a bad ground caused the fuel pump to start to fail (no idea what brand fuel pump is in it, I know it was changed a little over two years ago by the previous owner) I'm leaning toward the fact I may have had more than one issue going on. Any thoughts would be much appreciated.

jordan96xj

Although the driveability symptoms you are observing (transient stalls) could be caused by a failing fuel pump, I don't think that would explain what is going on with the dash cluster. A total dropout of the speedometer and tachometer signals.

Does this -ever- happen at idle in the driveway?

Brian Day

No ive been unable to recreate the issue at idle, even when doing a harness shake test nothing, I've driven it a few times now today and the dash cluster hasn't done it since I cleaned all the grounds and checked electrical connectors.

jordan96xj

The symptoms seem like what would happen if the PCM disconnected the ground from the ASD relay. Which is what it would do if it went without signal from the engine timing sensors for a few seconds. I assume the 99 still has a distributor and rotor/cap. If so, I would either be suspecting that a poor quality CPS was installed the last time around (what brand was it?). Or perhaps the Camshaft Position Sensor (under the distributor cap) is not providing a good signal.

Was the last crankshaft position sensor that went in a Mopar OEM sensor?

You mentioned that it was oem, but there is also a company called "oem" that makes sensors (Original Engine Management is the name). So did you personally get a Chrysler/Mopar sensor and have it installed? Or did someone say that they put in a "oem" sensor?

Maybe a better way to ask the question, is how much did you pay for the sensor?

Brian Day

It's a moparparts.com cps sensor, the distributor is new all internals are new as well, ecm was replaced also less than a year ago. I swapped out the ASD relay with fuel pump relay to see if that was the issue and no change. But like I said since I've cleaned the engine grounds the problem has not reoccurred. Because of it quitting on me I've only driven it a few times since though.

jordan96xj

And this time when it quit on you did the dash stay active? Or did the needles fall like the video?

Brian Day

It just quit as if I it ran out of fuel, all the lights on the dash came on as if you had just turned the key on normally

jamurrin

Well, most auto parts stores will lend you a fuel pressure gauge. (They make you buy it to a credit card, then when you return it, they credit your card back.) Connect it to the Schaeder valve (under the black plastic dust cover) on the fuel rail to test.

I can imagine your original issue being a combination of weak battery and weak fuel pump. No gas -> engine stall -> alternator slows -> alternator voltage dips. Whatever the cause the electrrical is better, but maybe another issue is still there. Either way, testing the fuel pressure is relatively easy and free.


Oh, and just for good practice, when I clean my ground connections, I also like to check/clean the (+) terminal at the battery, the starter, and the alternator.

Brian Day

I did a fuel pressure test, when I turned the key on the fuel pressure did not come up then cycled the key tell I got fuel pressure it came up to about 40psi then drops right back down to 0psi then I started it. It held pressure at about 47-48psi while running it drops a to about 44-45psi when I run the throttle up to about 2500rpm when I shut it off the pressure drops to 0psi immediately.

wk jeep

Just put fuel pump on 05 Cherokee 4.7 because of lack of pedal response and starting issues. It ran fine for 45 miles now want start people are telling me crankshaft position sensor trying to get some info from your guys it'll only turn over will not crank NEED HELP ASAP ONLY VEHICLE

Brian Day

I think you'll have better luck starting your own thread, still haven't figured out the entire situation here plus your rig is a completely different animal then this one.