Yj dies while driving

Raeverd

New Member
Joined
Jun 22, 2022
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7
Location
Effingham illinois
I have a 95 2.5 yj. A couple weeks ago it died while driving down the highway. It would not start back up at first but after a few minutes it started. Drove about a half mile and it died again. Waited a few minutes and it started. After that it ran just fine for a couple of weeks. Then 2 days ago it started doing the same thing. Dying while driving down the highway. I was pretty far from home so I tried getting as close as possible and all together it died 16 times. It seemed like the longer I waited to start it back up the further I could go before it would die. Then the last time it died it just wouldn’t start back up. So I had it towed home. I can hear the fuel pump kick on when I turn the key on and check the pressure at the rail and it was good. I checked the cps with a multimeter and it was bad so I replaced it today. Before I replaced it I tried starting it a few times with no luck. After I replaced it it started up no problem. Took it for a test drive and about 10 minutes into it it died. And I started the procedure all over again. This time it died 3 times on my way back home. There are no lights on on the dash and I did the code thing with the key and just got 33 and 55. Which I don’t have an ac so nothing is showing up. I’m at a loss. Anyone have any idea why it would start after changing the sensor then start doing the same thing all over again?
 
I bought my CPS from Napa after mine went bad. I had no problems after. Do you have an automatic or a manual? The automatic CPS needs a spacer on the head of the sensor before putting it in the hole. I am not sure if the manual CPS needs a spacer.

If you didn't put the spacer I would believe the sensor is not at the right distance from the flywheel/driveplate and it is causing an intermittent signal. Though, the CPS should throw a code.
 
I bought my CPS from Napa after mine went bad. I had no problems after. Do you have an automatic or a manual? The automatic CPS needs a spacer on the head of the sensor before putting it in the hole. I am not sure if the manual CPS needs a spacer.

If you didn't put the spacer I would believe the sensor is not at the right distance from the flywheel/driveplate and it is causing an intermittent signal. Though, the CPS should throw a code.
Manuals do not need the spacers, luckily. Just bolt on and go.
 
I bought my CPS from Napa after mine went bad. I had no problems after. Do you have an automatic or a manual? The automatic CPS needs a spacer on the head of the sensor before putting it in the hole. I am not sure if the manual CPS needs a spacer.

If you didn't put the spacer I would believe the sensor is not at the right distance from the flywheel/driveplate and it is causing an intermittent signal. Though, the CPS should throw a code.
Do you mean a grommet like the one in the link or something else? I have an auto and no spacer. Part number of link of where to buy one?

 
Do you mean a grommet like the one in the link or something else? I have an auto and no spacer. Part number of link of where to buy one?

No, I am not sure what that is.

What I am talking about is this:

It is a sticker that goes on the tip of the CPS. It will allow you to place the CPS close, but not too close to the drive plate. When you start the vehicle, the drive plate will rip the spacer off and your sensor will be in the correct position from the drive plate. It is about a mm of a distance.

Now, the NAPA link I posted, do not be fooled thinking you will be receiving a box of spacers for $8.00. You only get one spacer for $8.00. There are a few alternatives you can find online to use, I can't remember the alternative. Packaging stickers I believe.
 
It’s a manual. I thought I had it fixed. Unhooked the battery overnight and tried driving it this morning. Did great with no dying until about noon. Then started dying and wheat would restart it would only go about a quarter mile before shutting down again.
 
Just guessing that it's maybe temperature related and a poor electrical connection. It's worth your time to remove and clean every relay and electrical connector you can find. Get a good spray contact cleaner to help. 20+ years of being a Jeep adds up and I've found corrosion on every connector.
 
Ok guys after replacing the cps twice it needed up not being a faulty sensor. After putting the new one in it wouldn’t even start and had to be towed home. Again. Checked the fuel pressure on the rail and there really wasn’t any this time and I could not hear the fuel pump kick on. So I replaced the pump. Started right up. Took it for a test drive and got about 3 miles and it died. Then the 3 miles back home it died 6 more times. But this time the engine had a rough idle to it. So I got a new fuel filter and just replaced it. Pulled out of the drive way and it died. Took it down the road a bit and it did fine. Now I’m on another test run with it and about 5 miles into it it has died 2 times already. Each time it won’t start I’ve replaced the map sensor, cps, fuel pump and fuel filter and after each one it starts right up and drives for a bit. Sometimes it will go less then a half mile sometimes it will go 20 miles. I’m at a loss. I don’t know what I should check next. I don’t have any codes and my check engine light doesn’t come on. But after changing the fuel filter the rough idle went away.
 
Disconnect the fuel line from the fuel rail at the engine, put the open end in a big bucket or gas can, and run a jumper across the fuel pump relay socket to make the pump run continuously while pumping fuel into the gas can. Do it until a few gallons have passed through to make absolute certain the line or filter isn't getting clogged over time.

I've read about globs of junk in the tank which block the fuel flow at random times.

Just be extra careful when dealing with raw gas and fumes.

When it dies can you put a spare sparkplug on a plug wire and see if it is sparking? Just lean the plug against the engine somewhere.
 
Latest update. Jeep starts up after waiting a minute or so after dying. However, it does not die if I go in reverse and has now started to die as soon as I try to drive forward. It also is making a whining noise when I turn my steering wheel which I suspect is the power steering and when I let go it almost dies. I checked the power steering fluid and it’s full but was hot and had a lot of little bubbles on the top. After letting it sit with the battery cable off, I started it and let it idle for about 5 minutes and it just seemed a little too hot under the hood for only idling for a few minutes. I have checked and my oil is good and my reservoir tank is at the full mark. I’m not quite sure what temp it’s running at cause my gauge hasn’t worked for the last couple of years. I’ve checked my relays and they all are working. I read on here somewhere to check fuse #5 cause it is for the fuel pump and auto shutdown relays and it was good.
Tomorrow I will do what Flyer58 suggested with the fuel line at the fuel rail. Along with cleaning the relays and connectors. Thanks for all the advice so far.
 
Disconnect the fuel line from the fuel rail at the engine, put the open end in a big bucket or gas can, and run a jumper across the fuel pump relay socket to make the pump run continuously while pumping fuel into the gas can. Do it until a few gallons have passed through to make absolute certain the line or filter isn't getting clogged over time.

I've read about globs of junk in the tank which block the fuel flow at random times.

Just be extra careful when dealing with raw gas and fumes.

When it dies can you put a spare sparkplug on a plug wire and see if it is sparking? Just lean the plug against the engine somewhere.
I pinched my fuel line between the frame and a rock. The engine ran fine for 2 miles and would die. I would sit for 5 minutes. and the pump pressure would force fuel past the pinch point and refill the fuel line past the pinch. drive 2 miles set 5 minutes. do it over and over. also remove your coil, shake it, if it rattles buy a new one
 
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Hello did you find out what was the issue in your YJ Jeep? I have a Laredo wrangler 87 and it is also dying. My mechanic replaced fuel pump and at this point he told me he hasn’t found the reason of my jeep dying suddenly. Please let me know if you have a clue. Tks!
 
When was the last time the battery and ground cables were replaced? Too many times, owners chase their tails and throw parts at running issues when the battery and ground cables have never been replaced. I've cut apart cables that looked good on the outside, but the inside of the cable was a tube of corrosion. Battery cables are a consumable item. They need to be replaced periodically. All the sensors on the Jeep work on a 5 volt reference signal and are very ground sensitive.

On top of that, we need a full set of "vitals" for your Jeep.

Fuel pressure, which has been asked for a few times and we still haven't seen any numbers.

Compression Test

What do your plugs look like?

You're going to have to use a more systematic approach, or you're just going to be throwing part$ at the problem until you get lucky.
 
Latest update. Jeep starts up after waiting a minute or so after dying. However, it does not die if I go in reverse and has now started to die as soon as I try to drive forward. It also is making a whining noise when I turn my steering wheel which I suspect is the power steering and when I let go it almost dies. I checked the power steering fluid and it’s full but was hot and had a lot of little bubbles on the top. After letting it sit with the battery cable off, I started it and let it idle for about 5 minutes and it just seemed a little too hot under the hood for only idling for a few minutes. I have checked and my oil is good and my reservoir tank is at the full mark. I’m not quite sure what temp it’s running at cause my gauge hasn’t worked for the last couple of years. I’ve checked my relays and they all are working. I read on here somewhere to check fuse #5 cause it is for the fuel pump and auto shutdown relays and it was good.
Tomorrow I will do what Flyer58 suggested with the fuel line at the fuel rail. Along with cleaning the relays and connectors. Thanks for all the advice so far.
Hello did you find out what was the issue in your YJ Jeep? I have a Laredo wrangler 87 and it is also dying. My mechanic replaced fuel pump and at this point he told me he hasn’t found the reason of my jeep dying suddenly. Please let me know if you have a clue. Tks!