Hi Everyone,

It's been a while since I've been here but here's my situation. I have a 2004 Disco 2, remaned engine about 17,000 miles ago. Disco is running fine but now will not go into overdrive because of p0741 code of "Torque Converter Clutch, Low Performance, Stuck Off"; and p0734 "Gear 4 Incorrect Ratio."

I've had the transmission drained (which didn't look bad) and refilled twice with Castrol recommended ATF and added Lucas Slip Fix to the mix. I've driven it for the past week and no change. I'm thinking it's the solenoid but can't find a replacement solenoid anywhere. On the p0734 code, some links and threads here are pointing to replacing the MAF sensor.

Any thoughts or suggestions are greatly appreciated.

 

Anyone?

 

No OD. TC will usually lockup in 3rd or 4th but often not that noticeable for those expecting an OD like experience. The codes don't cause issues but may point you towards the causes. If you do a forum or wed search for TC LU etc., there have been a few threads in the last year or two you may find helpful. If you do a web search you may find a couple of good LR ZF trans manuals with some good T/S info. The solenoid may or may not fix your issue and a good starting point. It's available but you'll need to search for ZF trans parts not LR specific.
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Thanks Number9, I am exploring the forums on the TC and LU, etc. and have already found some good points to follow up. And I think I've found the ZF solenoid that may be the culprit. I will continue and keep the forum posted on progress.

Coors, thank you! I will unplug my MAF and see if it makes a difference. I recently had it cleaned and by reading here, a few posts suggest cleaning is not good for Bosch MAFs. I've ordered a new MAF and we'll see if it makes a difference. I will keep you and the forum posted on progress.

 

Explore the possibility of not engaging overdrive because of wrong/missing temperature sensing. OD is enabled only above about 66C. What I do not know is if that obeys coolant or transmission fluid temperature.

 

Externet, thanks for the reply! So you're saying it could be the temp sensor?

 

You may have already found it by searching......2nd half of this manual is good for the D2s....http://rave.stringsandints.com/Land%...n%20System.pdf

About the temp.....the trans fluid temp sensor has noting to do with LU. If coolant temp working it won't prevent LU. Very unlikely unless the TCM tango uniform. Below is from another manual......https://www.google.com/url?sa=t&rct=...rqszmyafJEPRwh

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Thanks Number9 for some clarification. And just to clarify on my part, the "NO Overdrive" is a permanent fact right now. So while I can appreciate your explanation of coolant temps per say, I don't think that's the issue since OD doesn't happen at all. And this all happened kind of sudden. Otherwise, Rover was fine. I just took a 2-hour drive at freeway speeds of 60-70mph and my Overdrive did not kick in. Am I missing something other than MAF test (possible replacement) and replacing the solenoid? I am going to try the "stall test" suggested here.

 

I have a P0734 I'm also dealing with. In my research I've heard the MAF can cause the the P0734. I found another thread somewhere that stated the ECU uses the MAF to trigger the OD. I have some broken clips on my air box lid I'm going to try and replace that first.