1994 Cherokee stalling

I know this questions has been asked in here before, but I've run out
of ideas. I have a '94 Jeep Cherokee with a 4.0 engine. It's got
151,000 miles and its stalling at random times. Mostly when just
driving along on the highway.

Here is a list of things I've already done ...

1. Replaced the crank sensor
2. Replaced the MAP sensor
3. Replaced the computer
4. Cleaned throttle body, Idle Air Controller, crank sensor connector
5. Bypassed wiring harness from computer to crank sensor
6. Replaced the fuel pump and fuel filter
7. checked ground wire from block to firewall
8. checked ground from battery

The computer is still showing codes 11 and 12 when it stalls. If
anyone has any suggestions I would really appreciate it. Thanks.

Rob

First u must determine if the fuel system or ignition system
is causing the problem.
In the meantime it appears you have become very proficient at fixing things
that are not broke.
Sounds like the ignition module is failing when it heats up,
The module is nothing more than a transducer that
converts a magnetic signal into a electrical signal
which triggers the coil.
You say that the crank trigger (magnetic switch)
has already been changed so let's rule that out.
The module or transducer may be mounted integrally inside a ignition box
(similar to older fords)
I am not that familiar with your particular ignition system,
but I'm sure you have some type of control unit or
"little black box".
What do those codes that are stored in RAM tranlate into:
I'm sure 1 of them is probably VSS (vehicle speed sensor), but what is the
other one translated.........
--
Mad-Dog
'79 Chevy K-10
Slightly modified
--
"themophead" <[email protected]> wrote in message
news:[email protected]...
> I know this questions has been asked in here before, but I've run out
> of ideas. I have a '94 Jeep Cherokee with a 4.0 engine. It's got
> 151,000 miles and its stalling at random times. Mostly when just
> driving along on the highway.
>
> Here is a list of things I've already done ...
>
> 1. Replaced the crank sensor
> 2. Replaced the MAP sensor
> 3. Replaced the computer
> 4. Cleaned throttle body, Idle Air Controller, crank sensor connector
> 5. Bypassed wiring harness from computer to crank sensor
> 6. Replaced the fuel pump and fuel filter
> 7. checked ground wire from block to firewall
> 8. checked ground from battery
>
> The computer is still showing codes 11 and 12 when it stalls. If
> anyone has any suggestions I would really appreciate it. Thanks.
>
> Rob

10 to 1 it's a bad ignition module. I had the same problem, replaced it with
one from a junkyard for $50, and it has run fine ever since.


"themophead" <[email protected]> wrote in message
news:[email protected]...
> I know this questions has been asked in here before, but I've run out
> of ideas. I have a '94 Jeep Cherokee with a 4.0 engine. It's got
> 151,000 miles and its stalling at random times. Mostly when just
> driving along on the highway.
>
> Here is a list of things I've already done ...
>
> 1. Replaced the crank sensor
> 2. Replaced the MAP sensor
> 3. Replaced the computer
> 4. Cleaned throttle body, Idle Air Controller, crank sensor connector
> 5. Bypassed wiring harness from computer to crank sensor
> 6. Replaced the fuel pump and fuel filter
> 7. checked ground wire from block to firewall
> 8. checked ground from battery
>
> The computer is still showing codes 11 and 12 when it stalls. If
> anyone has any suggestions I would really appreciate it. Thanks.
>
> Rob

> "themophead" wrote ...
>> I know this questions has been asked in here before, but I've run out
>> of ideas. I have a '94 Jeep Cherokee with a 4.0 engine. It's got
>> 151,000 miles and its stalling at random times. Mostly when just
>> driving along on the highway.
>>
>> Here is a list of things I've already done ...
>>
>> 1. Replaced the crank sensor
>> 2. Replaced the MAP sensor
>> 3. Replaced the computer
>> 4. Cleaned throttle body, Idle Air Controller, crank sensor connector
>> 5. Bypassed wiring harness from computer to crank sensor
>> 6. Replaced the fuel pump and fuel filter
>> 7. checked ground wire from block to firewall
>> 8. checked ground from battery
>>
>> The computer is still showing codes 11 and 12 when it stalls. If
>> anyone has any suggestions I would really appreciate it. Thanks.

11 = No crank reference signal detected during engine cranking.
Intermittent loss of either camshaft or crankshaft position sensor.
CKP sensor target windows have too much variation.

12 = possible loose battery terminal, connection, or the battery
has been disconnected within the last fifty engine starts.

that leaves the camshaft position sensor in the distributor
or its connector.

Checked the distributor for oil/crud?
http://members.cox.net/wilsond/distributor/


--
-- DougW -- 93 ZJ 4.0 http://members.cox.net/wilsond
HESCO Supercharger - 300W IASCA Stereo - Edelbrock IAS Shocks
Gibson Exhaust - rear DCpower - custom gauge install - Stillen Rotors
Banks Header - and BEER, in the fridge!

"DougW" <[email protected]> wrote in message news:<l5lIc.46538$Lh.25620@okepread01>...

> 11 = No crank reference signal detected during engine cranking.
> Intermittent loss of either camshaft or crankshaft position sensor.
> CKP sensor target windows have too much variation.
>
> 12 = possible loose battery terminal, connection, or the battery
> has been disconnected within the last fifty engine starts.
>
> that leaves the camshaft position sensor in the distributor
> or its connector.
>
> Checked the distributor for oil/crud?
> http://members.cox.net/wilsond/distributor/

After reading the message from MadDog, I took off the distributor cap
and cleaned the contacts and the button. I also checked the connector
and cleaned that up. It seems to be running a bit better but it's
still stalling. I was stalling every 500 feet or so, and after I did
that I was able to drive about 100 miles in the last 2 days without a
stall. I will look into getting a new/used ignition module. Thanks so
much for your help.

Rob

[email protected] (themophead) wrote in message news:<[email protected]>...
> I know this questions has been asked in here before, but I've run out
> of ideas. I have a '94 Jeep Cherokee with a 4.0 engine. It's got
> 151,000 miles and its stalling at random times. Mostly when just
> driving along on the highway.
>
> Here is a list of things I've already done ...
>
> 1. Replaced the crank sensor
> 2. Replaced the MAP sensor
> 3. Replaced the computer
> 4. Cleaned throttle body, Idle Air Controller, crank sensor connector
> 5. Bypassed wiring harness from computer to crank sensor
> 6. Replaced the fuel pump and fuel filter
> 7. checked ground wire from block to firewall
> 8. checked ground from battery
>
> The computer is still showing codes 11 and 12 when it stalls. If
> anyone has any suggestions I would really appreciate it. Thanks.
>
> Rob


I don't want to speak to soon, but I think I may have figured out the
problem. It seems that it was either the fuel pump relay or the Auto
Shutdown relay that was the problem. I wish the dealer would have
thought of that before I bought a new computer. Either way though, it
seems to be working. Thanks for your help guys.

Rob