Please help re 99 D2 not going into 4th

[lifestyler]

Hi Everyone

It's a bit late but I thought I'd let everybody know that the heater throttle body connection was leaking coolant and this ran down the back of the engine and onto the O2 sensor harness. This resulted in a short of some sort and screwed things up. I fixed the coolant leak onto the O2 sensor and all was resolved.

I think that if your D2 has issues shifting into fourth and is idling OK, then look for this leak and if there isn't a leak then look at the O2 sensor/s rather than the MAF...but who knows with Disco's

Cheers

Erron

 

[gmookher]

note to self:

order TB gasket kit

 

[KyleT]

You can re-baseline your TCM (trans control module) by having someone with t4, handheld or the like reset the adaptions. it "learns" your driving style and changes shift patterns a little.

 

[JohnB]

4th gear is also temp related. I don't know where the tranny gets it's temp signal from but it needs to be warmed up for overdrive to kick in. This may be only on basic under 40 mph conditions. Highway may be speed related.

 

[I HATE PONIES]

Hi Everyone

It's a bit late

3 Years isn't that late. Glad you got it sorted.

 

[hafaday]

4th gear is also temp related. I don't know where the tranny gets it's temp signal from but it needs to be warmed up for overdrive to kick in. This may be only on basic under 40 mph conditions. Highway may be speed related.

the trans cooler has a temp sender in it, also the transfer case has a temp sender (on my d2). i do not know if they report independent or together. but i will say, during the winter, if i hop in the truck with out letting it warm up. it will take a few miles (no more 5) at 40-45 before shifting into 4th gear. if already warm or the summer time, no problem.

i would love to have a wiring schematic for this vehicle. any one have a link or know where i can get one?

 

[p m]

i would love to have a wiring schematic for this vehicle. any one have a link or know where i can get one?

search for Rave CD

 

[JohnB]

Hi Everyone

It's a bit late but I thought I'd let everybody know that the heater throttle body connection was leaking coolant and this ran down the back of the engine and onto the O2 sensor harness. This resulted in a short of some sort and screwed things up. I fixed the coolant leak onto the O2 sensor and all was resolved.

I think that if your D2 has issues shifting into fourth and is idling OK, then look for this leak and if there isn't a leak then look at the O2 sensor/s rather than the MAF...but who knows with Disco's

Cheers

Erron

I should have looked at the post dates on this. Glad you got it shifting better. That throttle gasket is a real POS. I replaced mine with an updated kit from Rover. Which then leaked within 6 months.

O2 sensor tied to the tranny only on a Rover. I would think that even with a shorted O2 the system would go into a base setting.