Still havin some problems!

Ok so I posted on here a couple months ago about my wife sinking our xj in a river. I was just asking stupid typical questions on what everyone though I needed to replace or fix.

The jeep is a 2000 xj with a 4.0l, auto trans, 4 wheel drive and is right hand drive.

Well since then I have replaced the both O2 Sensors, all the sparkplugs (double checked the gap and made sure it was right), the TPS, every fluid in the jeep (still need to flush the trans one more time I think though) and checked the compression which looked great.

Ok so now im that I'm at this point the jeep still doesnt run great. It still misses on occasion, when you get on the throttle it takes a secone for it to register and start to accelerate, When you floor it from a stand still the trans shifts at 3000 rpm no matter how hard on the throttle, Whe you let of the throttle it either doesnt catch idle and dies or falls down to around 150 or 200 rpm, and the check engine light still is on.

So now what I'm trying to figure out is what do you guys think the next step is? The guy here at the shop on base told me I need to replace the computer, but trying to hold of on that till last if I dont have to. I think the trans shifting wrong might be cured be getting it flushed again to get ALL the water out since it still looks a little like milk. And hopefully I can just get the codes reset on the computer to get the light off.

Any help again on this stuff guys and girls would be such a huge help. Being over in Japan and owning a jeep is kinda a PITA, No one knows anything about them and I either have to order parts off line or pay stupid ungodly amounts for them! Thanks in advance!!!! :scottm:

Symptoms could be from bad TPS. Search for write-ups on checking that with an analog voltmeter. I see that you changed it, but it seems like the most likely candidate for your symptoms. Did you check for voltage going to the TPS? Maybe not the TPS, but wires/connections involved.

I haven't checked that but will maybe today, just gotta find a volt meter. Could it be from any other sensors? Or do you think maybe the computer could be bad?

Could be! You need to test. The 2000 also has the key recognition system built in. Do you have dealerships to burn in the computer for your key. Search to find more. You need to test more with a voltmeter. Only cost $10 max. Actually called multimeter because they do volts, ohms, amps.

Ok what other sensors should i be testing? And where would I get the voltages that they need to be at?

Most of the sensors run from the 5V supply coming from the computer. They are powered up on a common circuit. One bad one can pull the voltage to the others down.

I'm no expert on this topic but if you can, check to see if the engine control computer is throwing codes. Seeing that your in Japan, I'm not sure this is an option.

Well, one thing, rather than just guessing, why don't you simply pull the codes and see which one(s) is/are set ?
That'll go a long way towards telling you where/what to look at.



Fred

have you scanned the codes? the light is on for a reason and typically the computer will tell you why that is by scanning the codes. fix the codes... should run right.

I tried having the shop here run the codes, but they only have a japanese scanner which doesnt work very well IMO. But when he ran it thorough the chrysler setting it said it couldnt connect with the ecu, but when he just ran it through general OB2 setting it pulled a code for the TBS, replaced, and the 2nd bank O2 sensor, also replaced. Now im wondering if the computer is just bad???

Call around. maybe a motor pool person knows of someone with a U.S. scanner (made in China of course!)
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---Hopefully someone can verify it the below applies to your year Jeep----



On the older Jeeps you can disconnect the battery and hold the cable ends together 30 seconds or so and reconnect to battery and that resets the computer. It may run a little funny (just barely noticeable) while it is relearning (50 mi /few days). This clears old codes and throws "new" ones if any. Yours may not "know" there is a new TPS, etc.

Also I suggest - With the ignition OFF /Motor Off! operate the foot throttle full range, zero to max full throttle, about 20 times. (breaking in the TPS).
Do the battery "Reset"
Test run.

Is the fuel mileage way down? (Is it going into closed loop?)

Oh, the AW-4 takes about 12 qts to fully change.DEXRON 3 Only! (Do search on trans flush DIY)

Good Luck,
Orange

It is always best if you can post the exact code numbers here. The devil is in the details with OBD diagnostics and multiple codes relating to the same circuits and interpreting them is not always straight forward.

I'd concentrate on resolving the code/light and the driveability symptoms may very well disappear as well.

Replacing the computer is always a last ditch effort when EVERYTHING else has been ruled out. (a diagnosis of exclusion).

JohnXDoe said:

Ok so now im that I'm at this point the jeep still doesnt run great. It still misses on occasion, when you get on the throttle it takes a secone for it to register and start to accelerate, When you floor it from a stand still the trans shifts at 3000 rpm no matter how hard on the throttle, Whe you let of the throttle it either doesnt catch idle and dies or falls down to around 150 or 200 rpm, and the check engine light still is on.

:scottm:

Click to expand...

The lack of throttle response and poor shifting could simply be a cable adjustment. As a quick check, have somebody hold the skinny pedal on the floor and look at the throttle body to make sure the throttle plate is completly open. You can do a search on here for for the adjustment procedure. This has been discussed a few times over the years.

Let's see if this link works on adjusting the cable.

http://www.naxja.org/forum/showthread.php?t=1015963&highlight=cable+adjustment