Fuel Pump...or CPS??

Hi,

I'm new to this forum, and am having a problem with my 97 Cherokee(4WD 4.0) that started up 4 days ago. I was driving down the road, 5 minutes into going to work, and it stalled. I pulled over put it in park, and started up. Later in the day, it stalled, and didn't restart for about 3 minutes. Then that evening, it start hesitating and coughing, then stalled, and restarted after about 1 minute. So I changed the fuel filter that night. It ran fine for about 24 hours, though I didn't drive it as much. The next evening I was out. As I got in to go home, it stalled less then 10 seconds of being started. It wouldn't restart. After about 45 minutes of trying to restart it every few minutes, I called a tow truck(12am). So I figured the fuel pump had died. I bought a pump($95), and planned to try and install it today. I hadn't touch the car in 24 hours. Before I started the install today, I put the key in the ignition, and it started right up. So I decided to do some surfing, and see what else might be the problem. After finding this forum, it sounds more like the CPS is bad. I tried the "3-key turn trick"(thanks GregA), but only got code "12", not the "11" I was expecting.
(11 - No Crank Reference Signal Detected During Engine Cranking)

So, could it still be the CPS?

Do electric fuel pumps die immediately, or to the slowly stop working? Installing a new fuel pumps looks like a REAL pain!

Any info wold be greatly appreciated.
Thanks!

Hi,

I'm new to this forum, and am having a problem with my 97 Cherokee(4WD 4.0) that started up 4 days ago. I was driving down the road, 5 minutes into going to work, and it stalled. I pulled over put it in park, and started up. Later in the day, it stalled, and didn't restart for about 3 minutes. Then that evening, it start hesitating and coughing, then stalled, and restarted after about 1 minute. So I changed the fuel filter that night. It ran fine for about 24 hours, though I didn't drive it as much. The next evening I was out. As I got in to go home, it stalled less then 10 seconds of being started. It wouldn't restart. After about 45 minutes of trying to restart it every few minutes, I called a tow truck(12am). So I figured the fuel pump had died. I bought a pump($95), and planned to try and install it today. I hadn't touch the car in 24 hours. Before I started the install today, I put the key in the ignition, and it started right up. So I decided to do some surfing, and see what else might be the problem. After finding this forum, it sounds more like the CPS is bad. I tried the "3-key turn trick"(thanks GregA), but only got code "12", not the "11" I was expecting.
(11 - No Crank Reference Signal Detected During Engine Cranking)

So, could it still be the CPS?

Do electric fuel pumps die immediately, or to the slowly stop working? Installing a new fuel pumps looks like a REAL pain!

Any info wold be greatly appreciated.
Thanks!


Welcome to your first post on AF.
I have saw many problems with both. 95 $ sounds way to cheap for a fuel pump for one.

When no start check for lose of spark or fuel or both.
The best way to test fuel pump is with a fuel pump pressure gauge.
Also on codes you will need a scanner to get codes.
It should be OBD11.
Drop by your local auto parts place like auto zone. A lot of them give free scanner checks.
But a word of caution on free code checks.

Use Caution when getting the free code checks please.
Some parts places do offer free code checks. And also free repair advice. But beware. Just get the code no and post it back here and someone will help you.
They offer the free code checks in the hope of increasing there parts sales.
Almost all of them will also offer mechanical advice and some know what they are doing.
But just remember most of them are parts people pulling codes for free.
Not trained professional tech/mechanics. Even if they pull a 02-sensor code or another sensor related code it does always mean to replace that sensor and your problem will be fixed.
Please just get the code no and post it back here and we will help you.

MT

Agree with MT that they'll sometimes pump up what you need....so watch for the codes and write them down yourself. Sometimes it'll be good to get the codes twice to make sure, since you're unfamiliar with it.

That said, my gut thinks it's the Crankshaft Position Sensor. (Since I just replaced mine and had similar symptoms). You can always test for the fuel pump working, by turning the key to the "on" position....you can hear the fuel pump charge the system for a second.

Thanks for the information. I actually got the fuel pump at Auto Zone. I think I know someone with a scanner. Hopefully I can get the info tomorrow.

I would install a CPS first...it cheaper and you don't have to drain the tank.
My 97 has 131K on it, same fuel pump but they recalled the tank sender early in its life.

Thanks for the information. I actually got the fuel pump at Auto Zone. I think I know someone with a scanner. Hopefully I can get the info tomorrow.

You are welcome.
Proper testing will point you in the right direction.
If you find the fuel pump bad I would go the hole fuel pump module instead of just the pump. They had some problems with the factory seal rings in module.
If you get any codes post back code no.
Good Luck MT

Thanks for the information. I actually got the fuel pump at Auto Zone. I think I know someone with a scanner. Hopefully I can get the info tomorrow.


The code 12 means the batttery has been disconnected recently. Crank senser doesn't always trip a code. First check for spark and fuel before replacing parts,cheaper. When it stalls turn key back on see if you can hear fuel pump turn on should run about 3-5 seconds. Dale:2cents:

Just for sake of things.2000 Cherokee Sport. When my CPS went it would just crank--never heard the fuel pump activate--changed the CPS and when I turned the key to ignition U could hear the fuel pump come on---My mechanic wanted to change the pump before this (it was bad he said)---the cps when bad cuts off the fuel pump on this year some how.Just what I found out. So for an $80 CPS I saved $300 on a fuel pump--no problems since.

if the crank or cam sensor acts up, and the computer doesn't recieve a spark signal, the auto shut down relay or b+ latch relay will not let power go to the fuel pump, however, the pump will still come on for two seconds when you turn the key even if the crank sensor is toast depending on the year.