Stalling Problem

[Mad Steez]

Could it be my NSS?

 

[Mad Steez]

Another Update:

I got a new code today using this method http://www.naxja.org/forum/showthread.php?t=54095
The code was 25, looking at that chart it says Automatic Idle Speed (AIS) motor driver circuit shorted or target idle not reached. When i typed the code into Google, it took me to this web site http://www.obd-codes.com/trouble_codes/
I looked up the code, and it said P0025 "B" Camshaft Position - Timing Over-Retarded (Bank 2) - See Trouble Code P0022. i looked at the description and it fits how my xj is acting.

EDIT:

Upon further reading of this thread http://www.naxja.org/forum/showthread.php?t=54095 a post lead me to a site (http://www.kelleyswip.com/obd2.html)that gave me a list of codes using the key ignition trick. i looked for the code number and it says MAP sensor voltage too low/high


Whats going on?

 

[joe_peters]

Yeah, about the "key trick"--after sometime during 1997 that no longer works.

You need a code reader or scanner, or drop into a chain parts store and they will usually read your codes for free. Be sure to post up the full code number.

And the NSS won't stall the engine.

 

[Mad Steez]

Yeah, about the "key trick"--after sometime during 1997 that no longer works.

You need a code reader or scanner, or drop into a chain parts store and they will usually read your codes for free. Be sure to post up the full code number.

And the NSS won't stall the engine.

I did use a scanner and it gave me P0700-transmission control system malfunction. I was unable to get other readings because i had just disconnected the battery a few days prior to testing.

When i used the key trick i got a couple of numbers. Then when i would find out what that code means, the symptoms would state exactly how my car is running....
It seams to work for me

 

[Mad Steez]

Bump.

 

[Mad Steez]

Could this be causing my problems?

The rubber "L" grommet is cracked, brittle, and is lose once it is pushed back on that nipple. It will work its way lose after awhile.

 

[joe_peters]

Looks like an intake leak source--try plugging it and see what you get.

Looked in the FSM 00 to see what I could see, but the diagrams leave a bit to be desired. That "L" grommet and hose--can you tell where it runs? To the valve cover or the EVAP system?

 

[Mad Steez]

Looks like an intake leak source--try plugging it and see what you get.

Plugged it back in and my xj runs alot better, however, i still have the problem where if i hit a bump or turn just right the engine and the shut on and off repeatedly for about 2 seconds.

I used a OBDll scanner and pulled the code P0700-Trans Control System Malfunction.

 

[joe_peters]

Here is a list of trouble codes: http://www.obd-codes.com/trouble_codes/

Not a very specific code, the PCM is not getting data from the TCU within its pre-programmed parameters so it is throwing a fairly vague code.

Now, these late model beasts aren't my strong point, but I don't know of a condition where the lack of data from the TCU will kill the engine. I state this because you can unplug the TCU and drive your XJ from coast to coast and back, shifting manually.

However, for grinz and giggles, clear the code, unplug the TCU, and see how it drives.

I'm fairly certain that you have something causing an open or shorted circuit in the engine management and that is killing things.

 

[Mad Steez]

Here is a list of trouble codes: http://www.obd-codes.com/trouble_codes/

Not a very specific code, the PCM is not getting data from the TCU within its pre-programmed parameters so it is throwing a fairly vague code.

Now, these late model beasts aren't my strong point, but I don't know of a condition where the lack of data from the TCU will kill the engine. I state this because you can unplug the TCU and drive your XJ from coast to coast and back, shifting manually.

However, for grinz and giggles, clear the code, unplug the TCU, and see how it drives.

I'm fairly certain that you have something causing an open or shorted circuit in the engine management and that is killing things.

Ill try doing what you said tomorrow and ill post up.

What would cause this open/shorted circuit?

Im a noob when comes to electrical stuff.

 

[Mad Steez]

Looks like an intake leak source--try plugging it and see what you get.

Looked in the FSM 00 to see what I could see, but the diagrams leave a bit to be desired. That "L" grommet and hose--can you tell where it runs? To the valve cover or the EVAP system?

I just noticed this.

it runs along the fire wall over to the AC area, which would make it the EVAP system?

 

[joe_peters]

That's what I'm thinking.

 

[Mad Steez]

Would my EVAP system cause those stalling/cutting problems? If so how?

Also, could I have some info about that FSM you have for my 2000

 

[joe_peters]

You can purchase LICENSED reprints of Factory Service Manuals from: http://www.autobooksbishko.com/search.cgi?year=2000&make=Jeep&category=Shop+Manual

Unfortunately, the later model XJ manuals aren't on CD yet ($37); the hard bound body, chassis, and electrical manual set will run you $110 plus s/h. You can search on eBay for Bishko reprints, a couple dealers carry them and they run a little cheaper than direct from Bishko.

You can watch Craigslist and eBay for original shop manuals, but you will usually have to bid on them, and waiting for your year to become available on an auction can be frustrating.

I have had some success picking up various FSMs at local yard sales.

I can't remember the ORIGINAL OEM printer's website, maybe somebody will pop up with that info for you.

Please avoid pirated copies or "aftermarket" manuals. Most of the "aftermarket" manuals are crap or are really repackaged pirated materials.

The EVAP system captures fuel vapors from the tank, then "adds" those vapors into the intake manifold at appropriate times so they are burned as fuel, and the PCM adjusts the injector firming impulse duration to balance everything out.

Now, that looks to me like a vacuum source to the EVAP system, rather than the vapor inlet to the intake, but I could be wrong. Like any part of the fuel system, if it isn't functioning correctly the PCM will take steps to get things back into its pre-programmed ranges. A vacuum leak into the intake is going to swing the o2 sensor readings, the PCM will react trying to force things like the injector pulse, idle speed, and ignition timing until it things start to become a lot like a dog chasing its own tail.

 

[Mad Steez]

Now, that looks to me like a vacuum source to the EVAP system, rather than the vapor inlet to the intake, but I could be wrong. Like any part of the fuel system, if it isn't functioning correctly the PCM will take steps to get things back into its pre-programmed ranges. A vacuum leak into the intake is going to swing the o2 sensor readings, the PCM will react trying to force things like the injector pulse, idle speed, and ignition timing until it things start to become a lot like a dog chasing its own tail.

What should i do at this point? I did the TCU thing you told me to do. Before i disconnected the TCU my check engine light wasn't on. Now that i drove the jeep with out the TCU connected (and its connected now) the check engine light comes on and stays on.

If its something to do with the EVAP (or vapor inlet to the intake) were should i start?

 

[Mad Steez]

Now, that looks to me like a vacuum source to the EVAP system, rather than the vapor inlet to the intake, but I could be wrong.

I traced the lines and it goes all the way back to the gas tank. well to that black box just before the gas tank then another line goes to the gas tank.

 

[joe_peters]

yep, the EVAP system.

Fix that and see what you get.

 

[Leonkruger7]

I had the exact same problem. The engine wiring harness was chaffing against the head bolt at the back and opened the wires, that shorted the system.atriot: