please can anyone figure this problem out for me

my jeep is really causing my a lot of problems ... since I bought it I made alot of repairement for it .... but what to do I like it and I try to solve it's problems without thinking of selling it

the problem this time is that the check engine light would come on after 2 minutes for the first time and after it runs and turn it off and on immediatelt the light will come on , but if I leave it off for mre than 5 minutes it will not come till I wait for 2 minutes ...

can anyone please tell me about the fault ?

Thank you

What year is the jeep.

Extract the codes and post them...

to extract the codes:
Turn the key ON, OFF, ON, OFF, ON
The CHECK ENGINE light will begin to flash out the codes, if your jeep is equipped with digital odometer the code will appear in the odometer (P????), The codes are in double digit form with a short pause between digits and a long pause between each separate code.

ex. | pause | | = 1 pause 2 - code 12
| | | | | pause | | | | | - 5 pause 5 - code 55

| = Check engine light flash.

thank you ...

I will post the number of flashes soon ... but my problem is that the engine light now takes longer time than before to come one >>>>

sometimes 1 minute to flah for the first time and then disapear so the engine will run .... so what can be the problem????

well if the CE light isn't coming on as soon as you turn the key to the ON position then it is either a bad CPS or PCM.

Profile says it's a 93. :rolleyes:

Profile says it's a 93. :rolleyes:

Well I didn't read the profile. And this could have been a different jeep that wasn't added to the profile.

What year is the jeep.

Extract the codes and post them...
ex. | pause | | = 1 pause 2 - code 12
| | | | | pause | | | | | - 5 pause 5 - code 55

| = Check engine light flash.


The codes are :

| pause | |
| | | | | pause | | | | |

Mye be the codes show no problem but why does the Engline Light takes long only for the first turn on??? or if I leave the truck off for more than 5 minutes

The truck is running smoothly when it is ON .... the only problem is that I need to turn the key on the ON position and wait for about 1-2 minutes till the engine light comes .....then only the fuel pump and the spark (coil) will work so the engine can start ...

| <p> | | = 12; Battery disconnected w/in the last 50 starts
||||| <p> ||||| = 55; End of codes

Now, I'm paraphrasing the Hayne's Manual I have, but the gist of it is that the computer doesn't seem to think there's a problem. As dskob81 has mentioned, that coupled w/ the slow/non-existant lighting of the CE light @ startup would indicate either a dud PCM (computer) or the CPS (crank position sensor) is dying.

If it is the CPS, fredjacksonsan has already posted how do do an r&r of the cps on another thread here (http://www.automotiveforums.com/vbulletin/showthread.php?t=579517) for a 2000 I6 and the manual I have (dated for 93 JGC's thru 2004) seems to indicate the position of the sensor has remained fairly static & that walkthrough should at least give you a heads-up on how to get this fixed.

If you plan on doing this yourself, I'd invest in some form of manual, personally recommending either the FSM or a Hayne's manual before going too much further.

If when you turn the vehicle on you aren't hearing that fuel pump right away I'm going to say it's PCM.

If the CE light doesn't come on, then the FUEL PUMP won't kick on, the Ignition Coil won't fire and the Injectors won't open.

This is all caused by the PCM not getting a response from the CPS = bad CPS or thinking it's not getting a response from the CPS = bad PCM....

If when you turn the vehicle on you aren't hearing that fuel pump right away I'm going to say it's PCM.

that's right everything is not working till the engine light comes ON

by the way my jeep is simillar to yours ....

but when stop the engine and restart it immediately the light comes immediately .... it doesn't come on only if I leave it off for more then 10 ms

I have changed the CPS 1 and a half years ago ... it is still new ... and replced the disterbuter 6 months ago

Thanks to every one

It could still be the CPS, especially if it was an aftermarket brand (WELLS from autozone or BORG WARNER from pepboys and other part stores), if it is a mopar brand, then it is less likely to be an issue, but si still possible. The only other cause would be the PCM...

It could still be the CPS, especially if it was an aftermarket brand (WELLS from autozone or BORG WARNER from pepboys and other part stores), if it is a mopar brand, then it is less likely to be an issue, but si still possible. The only other cause would be the PCM...

I have unpluged the CPS WIRE but it still comes late ... I can hear some noise comes from the computer ....

I can hear some noise comes from the computer ....

Like a very high pitched squealing sound?

but when stop the engine and restart it immediately the light comes immediately .... it doesn't come on only if I leave it off for more then 10 ms

Exactly what my PCM did before replacement. Once I got it going I could drive anywhere, but if I shut it off for longer than a quick errand I had to wait to get it going again. And as it got worse it took longer and longer before it would work. You can tell when it's ready to work, just sit quietly in the Jeep and wait to hear the fuel pump noise. Once you hear it then crank the starter and you will start up.

Like a very high pitched squealing sound?



Exactly what my PCM did before replacement. Once I got it going I could drive anywhere, but if I shut it off for longer than a quick errand I had to wait to get it going again. And as it got worse it took longer and longer before it would work. You can tell when it's ready to work, just sit quietly in the Jeep and wait to hear the fuel pump noise. Once you hear it then crank the starter and you will start up.

Yes, this is what is going on with me ... it is ok till I shut it down... I need to wait for till the engine light comes on ....

anyway from where can I get a second hand PCM ...? and how much is it??
Can this PCM be repaired???


Thank you bringselpup

You need to get the part number and look for that number computer.

My number was on a sticker on the top of the PCM covered by a lot of road dust. It was so covered up I couldn't even tell there was a sticker there.

They are easy to get here in the US you can order them online or go to an auto parts store but I don't know how things are where you are. You might get lucky and find a used one at a salvage place. If you can buy stuff from Ebay you can look there but remember you need the same number as the one in you have.

Swapping it for a new one takes only 15 minutes.

Yes, this is what is going on with me ... it is ok till I shut it down... I need to wait for till the engine light comes on ....

anyway from where can I get a second hand PCM ...? and how much is it??
Can this PCM be repaired???


Thank you bringselpup


Friends is there anyway to repair the PCM ...

Now the problem seems to get worse ...

Thank you

It will continue to get worse until it won't work anymore. 3 months for me.

They are sealed units, this is not a fix you can do yourself. All you can do is get another and swap it.

What's the number on yours?

It will continue to get worse until it won't work anymore. 3 months for me.

They are sealed units, this is not a fix you can do yourself. All you can do is get another and swap it.

What's the number on yours?

I really thank you friend for your cooperation ....

I got the PCM out of the truck ...

I got the following numbers:

- THE BAR CODE :
MROD0099S1 either S1 or SI because it is not clear enough
56027 813
12/30/92


the following number was inside the PCM
I5E40280M01
On the cover
I5E40282M01

5602 7813 is the number you will need to know.

http://www.autopart.com/ecc/ECC1993JEEPGRANDCHEROKEE.htm

AT after the number on these items means Anti Theft NOT auto transmission.

But I found many brands e.g.
L6 93 model
Laredo L6 93/94 model
Limited L6 93/94 model
SE 94 model

having the same number 56027813
Are they all ok for my jeep??

And how to know if my Jeep has a Factory installed Anti Theft unit or not... because the PCM mighr differ or it does not matter if I fix anti Theft PCM or the other type?

Now I have fixed another PCM ....
The Engine light comes immediately...
The Engine runs but not that much good

the following flashes come

F short Pause
FF long Pause
FFF short Pause
FFFFF long Pause
FFFFF short Pause
FFFFF

So, can any one tell me what still wrong with my jeep, please?

Looks like 12 35 and 55

12 is battery recently disconnected, which would happen changing the PCM.
35 is open or shorted condition in the fan relay circuit
55 is end of sequence, you always get this


http://www.jedi.com/obiwan/jeep/dtc.html

Looks like 12 35 and 55

12 is battery recently disconnected, which would happen changing the PCM.
35 is open or shorted condition in the fan relay circuit
55 is end of sequence, you always get this


http://www.jedi.com/obiwan/jeep/dtc.html

I think there is no serious problem form what you said
Thanks friend ... you were always helpful...