Diesel engine loses power after low gear descent

[Yellowdog Lurker Find all posts View Profile Close Yellowdog]

Today I locked into low gear (high range 1st and 2nd) for a long bush road descent (Border Ranges Nat Park) to save on the brake pads. I used manual 1st and 2nd for maybe 15 minutes. Not steep enough for descent control.

At the bottom, I put it back into drive and it wouldn't accelerate beyond about 80kph. It made a noise like a petrol engine pinging, and felt rough like a diesel running on 3 cylinders instead of 4.

I turned the engine off and restarted it to reboot everything. Didn't fix it. Then I turned it off for a couple of minutes and restarted. This time it was back to normal - accelerating fine and no unusual noises.

The Prado is 3.0litre diesel GXL delivered in June 2015. Done about 9000 kms with no problems.

Anyone had anything similar happen after a descent holding high-range 1st and 2nd? Or any suggestions about the cause of the problem?

Mike

[Corigator Avid PP Poster! Find all posts View Profile Close Corigator]

Its intresting you raised that, Yellowdog. I have felt mine (08 GXL D4D) is doing the same thing. I haven't noticed the powerloss, but it does seem noisy after a long stint downhill, where presumably the injectors haven't been working for a while. It seems to quieten down after a few k's

Mine are new Denso injectors.

[nanbar Senior Member Find all posts View Profile Close nanbar]

I recently noticed that mine after a decent where I was braking an it geared down to help engine brake, after the decent and the road flattened out, it hung on to low gear extra long. Didn't shift like it does on the flat, it really revved out. No noises or loss of power though.

[Poppy Joe Member Find all posts View Profile Close Poppy Joe]

Mine does exactly that. I found if it won't change up come of the gas pedal then back on and it changes up. Seems to be the way to unlock it.

[Goggo Member Find all posts View Profile Close Goggo]

also I you knock into sports mode then back into drive it changes up then too.

[retroenduro Member Find all posts View Profile Close retroenduro]

Check out my thread in the knackered gearbox section as i had this but thought it was the gearbox slipping (towing a light trailer but descending into Adelaide in 3rd gear). I thought i read somewhere that its to do with the boost on the turbo and tripping it into a safe mode? Someone speculated it was due to larger diameter dump pipes on 3 inch exhausts fooling sensors etc and happened especially when towing? (i have one of these exhausts) Basically pulled away at the lights at the bottom and the car had nothing...limped home, turned it off and on again and all OK...threw 28 codes apparently tho...

[Greasemonkey Lurker Find all posts View Profile Close Greasemonkey]

Have had something similar happen now twice and I'm searching all over for an explanation, see post:

https://www.pradopoint.com.au/forum/...engine-braking

I'm wondering whether there have been any discoveries made in regards to this.