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Rockridge 4WD IS Taking Zone Offroad Suspension Lift Kits OPTIC ARMOR WINDOWS all sale now !!!!!!!!2003-2004 Jeep Grand Cherokee Headlight Dark Background wi

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Unread 09-27-2013, 03:29 PM   #16
remmons
Senior moments member.
2002 KJ Liberty 
 
Join Date: Mar 2010
Location: Vernal, Utah
Posts: 1,228
Glad that the 4.0 swap is a success! Good luck with the AW4 problem.

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2002 Liberty Sport 3.7. 2.5" lift. Mostly all stock.
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Unread 09-28-2013, 02:35 AM   #17
ALFDMAX
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1989 YJ Wrangler 
 
Join Date: Aug 2013
Location: Bucharest, Romania
Posts: 16
A graphic update... sorry but yesterday I have not enought time to post pics

The XJ shifter adapted, needed to buid an specific support to put it into a comfortable position.





By the way Iīve installed a SYE because I didnīt like the shaft position, and also a Posi Lok disconecter for the front axle



And a new rear shaft done starting from a front XJ shaft





And the YJ ready to go

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Unread 10-05-2013, 04:47 AM   #18
ALFDMAX
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1989 YJ Wrangler 
 
Join Date: Aug 2013
Location: Bucharest, Romania
Posts: 16
Well, I continue having problems with the AW4....

Transmission is ok, shifts well on manual without the TCU connected, but if I connect the TCU it only shifts at redline....

I think Iīve already read all topics regarding this problem, i performed testing from the AW4 repair manual.... and finally I concluded that my TPS sensor was bad.... was the only one that doesnīt give me correct values... I read the TPS adjusmet procedure and it says that the output voltage on the B pin of the square connector maybe 83% of the input voltage, so if I have an input voltage of 4,6v, the otuput should be about 3,8v.... but my TPS give 0,63v output.... (understanding that the flat connector that sends info to ECU is giving corect values and engine runs fine)

Well... I called one friend and asked him to take of the TPS of his Renix and give it to me for a probe... I changed the TPS (that was working fine on his XJ) and... surprise!... I have the same output voltage, 0,63 v.

So... what Iīm doing wrong?.... My friend has put my TPS on his ride and works fine.... why on my ride two different TPS are given wrong values?

My grounding is ok, every sensor ground is under 0,1v, flat connector is giving corect values...

I mention that Iīve tested all solenoids and are good, VSS is good, NSS is good.... and if I power directly the solenoids I have corect shifts (powering solenoid 1 = I have 1st, Powering solenoids 1 & 2 = I have 2nd, powering just solenoid 2 = I have 3rd, no powering any solenoid = I have 4th, and if powering solenoid 3 converter locks up) I canīt understand where is the bug.... Iīm pretty sure that itīs a TPS problem, but not caused by a bad TPS...

Any help will be welcome, thanks!
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Unread 10-05-2013, 08:59 AM   #19
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 13,730
What fault codes do you get?
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Unread 10-05-2013, 01:49 PM   #20
ALFDMAX
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1989 YJ Wrangler 
 
Join Date: Aug 2013
Location: Bucharest, Romania
Posts: 16
I have no possibility of get codes, no DRBII tester is available around here (Iīm in Romania).

So I proceeded performing the repair manual tests, first of all I tested if transmission shfted ok manual (without TCU conneced) and yes, I have 1st gear at 1-2 position, 3rd at 3 position and 4th at D position, R also works fine and obviously I have no 2nd without the TCU connected.

Also I performed pressure test, stall test and lag test and it gave me normal values.

So the transmission is ok from the mechanical point of view.

After this I checked each input to TCU, sonenoids are ok, NSS gave me corect values, VSS also works fine, brake switch works, the only input I've checked with wrong values is the TPS, but after trying with another TPS that worked fine at its original vehicle and notice it gave me exact the same values I suspect another kind of problem... not TPS, on fact I have checked my TPS (that is a brand new Standard Motors) in my friendīs XJ and also works fine with his transmission......

Maybe a bad TCU??, I cannot check this without DRBII tester...

My question is how a TPS, that is a very simple sensor (just a resistance), works fine with another transmission in another car, and when I put it on my ride it fails?....

Problem is with the output voltage, it must be about 3.8v and I obtain 0.63v... input is ok I receive around 5v and ground is good (less than 0.1v on it)....
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Unread 10-05-2013, 04:43 PM   #21
Que89YJ
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1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 13,730
Three only way it is possible it's if your throttle plate isn't closing right.
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Unread 10-06-2013, 03:06 AM   #22
ALFDMAX
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1989 YJ Wrangler 
 
Join Date: Aug 2013
Location: Bucharest, Romania
Posts: 16
No problem with the throttle plate, I think... itīs closing right and TPS gives me the right values on the ECU connector (flat cnnector)...

Iīve taken some measures this morning and I observe that I have some kind of power at the output wire when ignition is on and the TPS unpluged.... thatīs wrong, that wire must not send any voltage, is an input line to the TCU not a outpu line....

So I think I have a derivation somewhere... or some kind of problem with the infamous C101 connector.... I mention that when I swapped the engine and transmission I used the old harmness from the donor that wasnīt in a very good condition

First of all I go to cut that wire and will put a direct wire to the TCU...

Keep you informed.

Thanks for the feedbacks
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Unread 10-24-2013, 12:42 PM   #23
ALFDMAX
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1989 YJ Wrangler 
 
Join Date: Aug 2013
Location: Bucharest, Romania
Posts: 16
Sorry I was several days without net access....

Finally I got it out, the transmission problem was solved just cleaning the NSS

It runs nice, now is time to start with suspension upgrades

A pic on the trail...

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