TJ Johnson

Howdy all,
I had asked for help last week about high oil pressure at idle after changing out CPS.(Dave was Very Helpful)
Had SIL come over with his scan tool to set the CPS if necessary and when I started the jewel up I had a horrible spark/ark from under the coil pack that wasn't there when I changed the CPS!(it gets better folks, just hang in there!) Son-In -Law's scan tool couldn't find any fault with CPS(I got that part right!) and while running the scan the radiator which was leaking badly from the passenger side core to tank seam BLEW out the tank!!!!
Okay, I knew I was going to replace the rad anyways, so I got a replacement and replaced bombed out radiator and fixed the arcing under the coil pack(there's a whole story on the ***** you got to remove to replace the radiator)and every thing is good= holds temp as it should and the oil pressure is now reading normally (I did nothing to the oil sensor)
Checked and topped off tranny, got in and went for test drive....
NOW the thing won't come out of first gear! It wasn't having any issues before this. ( All this work was because of a bad PCS)
What's up?
Am I missing something?
TJ

TJ Johnson

Okay Folks,
I really wasn't expecting the internet to do a diagnostic and then fix it for me, my lead off post was more of a rant and vent.............
But seriously, it has me puzzled. I am not up to speed with my Jeep. I have worked and maintained my F150 4x4, Explorer, fox body 'stang and my family's cars and trucks.
The one repair guide I have right now says "take it to a specialist"for this problem. I would really like to do what can be done BEFORE paying some one.
"Can You Help A Brother Out?"lol
Where is test point for the tranny, I think it may be electrical more than linkage as it will go into reverse and drive, the gear selector will shift to all OD,2,1 with any effort.
What ever drive selection is used it starts off in 1st and stays there. It pulls off like a Jeep, torque to beat the band.

Bustedback

Check engine light on? Check the fluid level, if that checks out you may have a governor pressure sensor issue.

czettlera

There are hydraulic test ports on the transmission, where you can connect a pressure gauge to diagnose it. If you need it I can post the procedure for you.

TJ Johnson

Thanks for the replies Bustedback, czettlera.
SIL came over yesterday with his MAC Mentor scan tool. While the Jeep is displaying NO faults NOW, it did earlier when I had the spark arcing. Reseated the coil pack which took care of the arcing and the oil pressure gauge readout went back to normal as well the ABS indicator.
The Mentor tool found no hard faults in the memory, took the jeep for test drive. When letting off the gas he said the Mentor saw a shift to 2nd and briefly 3rd, but as soon a the throttle was moved right back to 1st. While this was going on we could feel no change other then deceleration you would feel from being in 1st.
We did find the CPS needed to be tweaked to get it in range, now the crank and camshaft sensors agree and engine wise everything is good, so we went deeper into the subsystems and the Mentor found 2 faults= a P1762 and P1753.
P1762="Sensor input greater or less than calibration for 3 consecutive Neutral/Park occurrences"
We could not find any info on the P1753. I'm getting under it to give it a look over to check all the wiring there and get a better look at the TV cable.
Oh and the TCM is good.
Thanks guys, I really appreciate it.
TJ

TJ Johnson

Got under my 2001 GC and was soooo hoping for a "ah-ha-that's what the problem is!" Nope, no dice. All connecters, linkages and the like appear to be okay.

Bustedback

I still leaning toward the governor pressure sensor and solenoid.

TJ Johnson

bustedback I think you are right, being a newbie to Jeeps I just this morning found out the self diagnostic feature on the Grand Cherokee.
While the CEL isn't lit, I did get "P 1762 " from the dash readout and followed by "dONE" which I suppose means that was the only code it had stored.
I imagine you are wanting to have the ability to reach through the screen and choke the living chit out of me now.......
Now to find the parts,hoping my SIL can get me some sort of discount with him being a certified mechanic.
TJ

Bustedback

That code is for the governor pressure sensor.

TJ Johnson

Yes it is, got me some wrenchin' to do.