Jeep died while driving tonight

That appears to be the oil pressure sender connector though it seems further to the rear than it should be. Could be that I'm having a little trouble getting oriented from the photo. Can you get a photo looking down onto it from the top?

The engine would not stop with the oil pressure sender connector disconnecting though it would cause a red Check Gauges light together with a zero oil pressure indication if it came unplugged.
 
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Jerry Bransford said:
That appears to be the oil pressure sender connector though it seems further to the rear than it should be. Could be that I'm having a little trouble getting oriented from the photo. Can you get a photo looking down onto it from the top?

The engine would not stop with the oil pressure sender connector disconnecting though it would cause a red Check Gauges light together with a zero oil pressure indication if it came unplugged.
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Good info!
I can get you an above photo too.
 
On second thought, you can more simply verify if that connector is for the oil pressure sender by leaving it disconnected and starting the engine to see what the oil pressure gauge does and if you get the red Check Gauges light.
 
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Ok, so where I stand now is I have to go to work to be able to buy more Jeep parts! Lol.

I've thoroughly cleaned the connections of the Crankshaft Position Sensor...and I still stalled out when I left my driveway for a test run, it started right up again though. I made it to the main road and it stalled out again, while idling and waiting to be able to turn. Also fired right back up today.

I drove to the gas station and filled up the tank as I had less than a 1/4 tank and I needed gas to attempt to drive to work tonight in it. Fingers crossed that I make it!

Also today I replaced all 4 O2 sensors in the midst of this crazy day, and ordered the new Crankshaft Position Sensor. Should be here this saturday. We'll take it from there to see IF swapping that does anything.

My stepdad really seems to think its the Fuel Pump though...might also be looking into one of those as I do not believe it has ever been changed out.
 
Had you told your stepdad that someone already checked your fuel pressure at the pressure test port right after the engine stalled and pronounced it ok before he said he thinks the fuel pump needs replacement?
 
I've had several fuel pumps go bad while driving and it was LIGHTS OUT, no restarts, like braking a timing belt.
Maybe I'm wrong here but was under the impression that fuel pumps weren't intermittent issues.
 
Jerry Bransford said:
Had you told your stepdad that someone already checked your fuel pressure at the pressure test port right after the engine stalled and pronounced it ok before he said he thinks the fuel pump needs replacement?
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I did, and I think he said something like you might be getting only 10psi when the specs could be between 40-50psi.

PS: The guy who checked it just pressed the valve with his fingers and fuel sprayed out, and not with a "gauge" to actually check the psi.
 
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The pressure is supposed to be very close to 49 psi. Borrow a fuel pressure gauge from Autozone (they're free to borrow after a making a refundable deposit) and verify what it is before buying a fuel pump.
 
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Jerry Bransford said:
The pressure is supposed to be very close to 49 psi. Borrow a fuel pressure gauge from Autozone (they're free to borrow after a making a refundable deposit) and verify what it is before buying a fuel pump.
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I just bought one off of Amazon, anyhow I hooked it up to the Schrader Valve and fired it up and its right at 50psi. When I turn the key to run, the psi jumps from 0 to 49 and after 5 minutes its at 22psi.

I also replaced the Crankshaft Position Sensor, the Camshaft Position Sensor, and the fuel pump relay...and while it hasn't died on me while driving yet, it has stalled out when I came to a sharp stop at a light once. It has stalled out on my climbing up a a short incline, and it always stalls out going from reverse to drive on a cold start. That reverse to drive thing really bugs me because its every time.

I have no clue what to do next...
Does this sound like a Fuel Pressure Regulator failing?
 
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A fuel pressure regulator only limits the pressure to no more than about 50 psi. It would not be the cause of low fuel pressure which would be caused by a weak fuel pump.

Did you install a Bosch fuel pump as is recommended or was it a store brand or aftermarket like an Airtex or Spectre?
 
Jerry Bransford said:
A fuel pressure regulator only limits the pressure to no more than about 50 psi. It would not be the cause of low fuel pressure which would be caused by a weak fuel pump.

Did you install a Bosch fuel pump as is recommended or was it a store brand or aftermarket like an Airtex or Spectre?
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I bought the Bosch Fuel Pump but have not installed it yet. Those readings were with the existing situation.

Does that sound like its the issue then?
Turn key to Run, pressure hits 49psi, then slowly drops to 25psi over 5 minutes = bad fuel pump?
 
EJD said:
I bought the Bosch Fuel Pump but have not installed it yet. Those readings were with the existing situation.

Does that sound like its the issue then?
Turn key to Run, pressure hits 49psi, then slowly drops to 25psi over 5 minutes = bad fuel pump?
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Sounds like it to me. Make sure your gas tank is as close to empty as possible before dropping it. Also be aware some of the plastic fittings on top of the gas tank will be brittle by now so be careful so nothing breaks.
 
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Jerry Bransford said:
Sounds like it to me. Make sure your gas tank is as close to empty as possible before dropping it. Also be aware some of the plastic fittings on top of the gas tank will be brittle by now so be careful so nothing breaks.
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OK so little update here,

First off...Jerry let me just say Thanks man you are awesome! I love these little tips and fun facts you toss into every conversation.
Secondly, my issue has gotten better but is not eliminated yet...

I dropped the gas tank and successfully installed the new fuel pump assembly. Since I was careful with those fittings, I did not break any and was able to reuse them! I did the old chisel & hammer trick on the retention ring too, and that worked perfectly, so no strap wrench needed. The only thing that gave me any trouble at all was 1 nut on the side with 3 bolts, the one near the exhaust was rusted and the bolt actually broke free from its weld and was just spinning. (That took some patients and improv to get off).

The Jeep actually does feel like it accelerates better and feels good with the new fuel pump on there! And while it has not stalled out on my while driving, it did stall out on me once at a red light while idling but fired right back up no probs. It kind of felt like it was idling good at 500-750rpms steady...and then just choked out.

I just ran a fuel pressure test through the Schrader Valve and heres where were at:

With key turned to Run, pressure hits 46psi then after 2 minutes it drops to 44-43psi and does not go lower than that.
With key turned to On, pressure hits 49psi and holds strong there while running.

What exactly does that translate to? Is there a cracking hose with a bad fitting or bad connection? Bad vacuum lines? Know of any good areas to inspect for wear and tear?
 
EJD said:
With key turned to Run, pressure hits 46psi then after 2 minutes it drops to 44-43psi and does not go lower than that.
With key turned to On, pressure hits 49psi and holds strong there while running.
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That confused me, there is no run position on the ignition switch. And when does it drop to 44-43, when the engine is not running?

But it holds steady at 49 psi when the engine is running? If that 44-43 psi is even after it sits over night, that sounds ok.

Still can't say why the engine stalled at the stop light, not sure where to go next with this.
 
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Jerry Bransford said:
That confused me, there is no run position on the ignition switch. And when does it drop to 44-43, when the engine is not running?

But it holds steady at 49 psi when the engine is running? If that 44-43 psi is even after it sits over night, that sounds ok.

Still can't say why the engine stalled at the stop light, not sure where to go next with this.
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Oh "run" I was told was the notch right before starting it, with not starting the Jeep I can hear the fuel pump start and the psi jumps to 46 then slowly drops to 43ish.

While engine running its right at 49.
 
EJD said:
Oh "run" I was told was the notch right before starting it, with not starting the Jeep I can hear the fuel pump start and the psi jumps to 46 then slowly drops to 43ish.

While engine running its right at 49.
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That all sounds fine so long as it doesn't drop much below that 43 psi after it sits overnight.
 
EJD said:
Ok "hoping" someone might have a suggestion or direction to go with this.

We were driving to the store tonight, hit 40something mph and the engine cuts off. We are now coasting down the road towards a stop light, I have no power steering, brakes are hard to depress, but still have all electric in the cab so I throw the hazards on. I shut the Jeep off, and try to restart it, and it just cranks and never turns over. I repeat this a few times waiting a couple minutes in-between attempts.

Just then, another TJ rolls up next to me and the guy says, "you alright over there?", so I tell the guy it just won't turn over and we stalled while driving. So he pulls over in front of us and gets out, then one of his buddies tools up across the street, and seriously asks if he can check the fuel pressure, like they were familiar with things like this, and he says there is good pressure up there on top of the engine through this little valve. The friend also actually had a scan tool so he plugs it in, thanks the Jeep for having the spot to plug it in being so conveniently located, and says its not throwing up any codes at all. The check engine light has never came on, so he says to me that usually when theres no codes and the Jeep dies, "its something stupid" causing it.

I have no idea where to go with this info besides calling a friend or posting up here in the hopes someone might have an idea or if this has ever happened to anyone before.

Any insight is greatly appreciated!
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Did you ever find the solution to your issue?? CPS or fuel pump? @tomtaylz seems to have the same problem.
 
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Alex01 said:
Did you ever find the solution to your issue?? CPS or fuel pump? @tomtaylz seems to have the same problem.
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Are we talking of the problem that I had when I started this thread or the problem that was still present at the end of the thread?
I only ask this because there was multiple issues that have all been resolved and i'de like to give you or @tomtaylz the best info.
 
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