Transmission Woes

The other day my "Check Engine" light fipped on-- I assumed it was an emissions issue (i.e. bad 02 sensors, cat. converter) as that was the last time I've had the warning light trip 10 years ago. While on the highway this morning my transmission started skipping, searching for gears.

I limped home keeping my speed to 55... Seemed to shift fine at lower speeds off the highway. I've had flex plate & bad torque converter issues (as diagnosed by 2 shops) had it re-tightened & lived w/ TC noise for several years.

Any folks dealing w/ this? Any estimates for repair? TIA

First, always state your basic information--it saves time for all concerned.

Second, get the codes read, then post up the actual numbers.

What TC noises have you been living with for 2 years?

What TC are you talking about? TC can be a transfer case or torque converter.

Sorry guys, here's more info--torque converter has been loud for years... was quoted $900 fix @ local Jeep dealership. I'm having the codes read later today.

1997 XJ Sport

Can you describe the sound, now that we know the volume? LOL

I just went through similar problems with my '96. Tranny didn't know what gear it wanted, TC would lock/unlock for no reason. Thankfully, it threw a code, and it was for the Throttle Position Sensor! It's taken out three of them since I had the 're-flash' recall for the '96s done in June of '09. I've asked the dealer what was involved in the re-flash, and of course they didn't know. I think, if it ever warms up, I'm off to Harry's to find an un-flashed computer (which the service manager didn't disagree with, wink wink!).

Just had XJ scanned-- threw codes PO700 & PO705 (sensor?) Going for estimate Monday...

Heyhar, That sounds like bad TPS sensors off the shelf, not a reflash computer issue!

For the OP, Tia, sounds like the NSS, Neutral safety switch may need to be removed and contacts cleaned. 705 codes inidcates it is having a data problem detecting the gear shifter position, which is the NSS!

http://www.obd-codes.com/trouble_codes/

P0705 Transmission Range Sensor Circuit malfunction (PRNDL Input)

P0700 is a general transmission code, not specific

Mike-The original went in December of '09, six months after the re-flash. I replaced it with a JY piece, and it was starting to act up in Oct. '10. Bought a new one from RockAuto, Standard's better of two, it immediately went nuts. Back to the JY, came home with three-the lowest mileage ones I could find-and all was well, and last week it's acting up again. Driving and shifting OK, but after an Interstate blast, it wants to idle at 2k for about 10-15 seconds, then comes down, idles smooth as glass. It's a weak high idle, as if it's only air and no fuel, as it won't overcome any braking, more an annoyance than a safety hazard. I'm the only one that drives it, anyway, so I don't worry about it catching my wife off-guard. I've also installed a NEW IAC, and the TB is spotless, as is the IAC chamber. It's not a strictly mechanical problem with the high idle, as I think the IAC is doing what it's told, by a confused TPS, which may or may not be getting erroneous signals from the computer. Like I said, it wouldn't hurt to have a 'virgin' unit to compare it to.

Townie said:

Just had XJ scanned-- threw codes PO700 & PO705 (sensor?) Going for estimate Monday...

Click to expand...

A good percentage of the time, as Mike mentioned, both of these codes are related to the neutral safety switch.

They can often be "refurbished" and returned to full function. As they are kind of expensive to replace, refurbishing is always recommended here.

Here is a link to a great article on fixing your NSS. Good luck!

http://bc4x4.com/tech/2010/jeep-neutral-safety-switch-nss/

birchlakeXJ said:

Here is a link to a great article on fixing your NSS. Good luck!

http://bc4x4.com/tech/2010/jeep-neutral-safety-switch-nss/

Click to expand...

That is a nice writeup. Go easy prying on the nut as the threads are soft aluminum. Take it apart inside a plastic bag just in case pieces start flying. Those little springs can get some distance!