Pajero Owners Club of South Africa

Am I an autobox killer?

Did a trip today with a rather heavy load and want to see if the limiits are beig pushed OR is there something else going on...?

Vehicle: Pajero Sport ...so 3.2 Diesel
Electronic auto box (gen ? equivalent?)?
Route: crappy hilly coastal road to Port Alfred from PE.
Trailer: double axle trailer with rails and expanded mesh 3m long x 1.6wide. same height as vehicle.(braked)
Load: 1300kg of pumps, sand and filters (GVM 2000kg)

General: Level towing not really a problem, obviously feel the trailer and takes a while longer to get to 120km/h. trailer wheels all ok, tyre pressures all adjusted for extra weight, trailer biased for 50-75kgs on ball.

Issues: as soon as ANY gradient is attempted, the experience deteriorates dramatically.
She started hunting like crazy, so I realized that she needed a bit of guidance and tipped her into 3RD and reduced speed to 110-100 km/h.
As hills presented greater challenges, went back to auto to let the gearbox decide what gear was best. worked ok, but certainly was wondering where the 120kW was hiding....

As the trip progressed, there would be hills where we flew up at 100km/h + and then only a few km later to be in 2nd, full taps and losing speed at 60 or 80km/hr!. I gave in very quickly with the full throttle sessions as i realised a boundry was reached.
I even tried using the cruise control to maintain 100km/h on some inclines, rationalising that the cruise control would only apply the required throttle as opposed to my trying to drive my right foot through the floor.... Apparently Jap engineers do not like it when engine requires full throttle in cruise control... it unceremoniously disengages and you get this sick feeling for a few seconds, checking the rear view mirror for expensive debris as you lurch forward. then you realise its just off and you need to get your foot back onto the accelerator.

Other observations: I hit a kudu two weeks after i got her amd part of the repairs was the replacement of the radiator, and coolers in the nose.
When I went to brakkeduine not long after, she exibited the same 'lack of drive' symptom.
The best way to describe it would be when ASC / traction control kicks in. ie. the engine revs / pull does not correspond to the accelerator pedal position.

So, poll time......
A) Is this just the engine and gearbox talking to each other, and keeping each other safe?
B) Is there perhaps a contamination problem ? (foaming???)
C) Am I an insensitive clown who should get a truck?

By no means a regular thing.
However, would like to guage if there is something deeper to be looked at.

Thanks

Alan

If you are getting indifferent behaviour at different times, I can only suspect the ecu is either keeping the engine or autobox cool.

Towing such a large load creates a lot of heat from the torque converter.

The pajero is a great tow vehicle but don't expect more than the. 120kw can give. Try and tow the same load with a 120kw petrol and you'll realise how competently the pajero can tow with what it has.

The sport does suffer slightly when towing due to the 4 gear box instead of the 5 gears like the gen 3/4.

Don't rush when towing. Sit back relax and enjoy the scenery. I drove that road yesterday...... Twice!

When an uphill approaches, gain a little extra speed before and as soon as it starts loosing speed, drop a gear so it slots at about 3000rpm and then use no more than 3/4 throttle to keep it there. If you need to use more throttle, rather slack of slightly and drop another cog.

I haven't towed much with mine but did tow a broken tractor and it's trailer out a muddy hill. It wasn't fast but slowly does it. That's the diesel way.

If you want to tow at speed, get a v10 touareg! But be careful, no amount of tech can slow momentum fast enough!

Happy towing and driving in your sport!

I had a similar problem, but not towing such a big load. (2002 3.2 Pajero) Spent a week in the Kruger, with cruise control set at just over 40 every day. No problems. Coming out of the park, my baby was sluggish and would not pull. Checked the trailer, temp, oil, water, tire pressure and what not, but no faults found. As soon as I found a long stretch of open road I floored it to see if the problem carried over to high speed driving. Billows of smoke! Kept it floored and suddenly she came alive! Seems that the low revs results in a carbon and or oil build up in the system, probably clogging the catalyser, as it needs higher temperatures to work. As soon as it had burned or blown out the deposits, the problem went away. I recommend a good run at 140+ (Wasn’t me Officer!) and try again.

A few thoughts:

• towing 2000kg at 120km/h? ...
• .... with a engine / transmission that possibly has a problem?

Wrong fuelling can ruin TD engine in 10kms!
Faults in the transmission could do the same to the transmission.

Maybe you should take it for a thorough check-up, diagnosis and dyno?

That has been the other thing bugging me.....
Saw on another thread where under light acceleration that there is this 'hesitation' from 2nd to 3rd.
Have asked my clevers to check if the firmware is up to date. I'm sure they just reset by removing power to ecu.

Towed with smaller trailer today.
Still not convinced it's just me.

the disconnect has to be at least 60 seconds long. 5 minutes without power is ideal to reset ecu.

4ePikanini wrote:the disconnect has to be at least 60 seconds long. 5 minutes without power is ideal to reset ecu.

I was taught that you should disconnect the battery and then switch on the lights and turn the ignition on and pretend to start the car. This will "drain" all the power from the wiring. Reset is achieved.

Starting this line of enquiry again.....

Just read Red Catspost on fuel regulator causing surging and slipping effects in auto box.

I wonder if this is also causing the power issues I've experienced?

In the sand outing when she was new, could not get her 'out of the blocks'
Refused to rev above 2200rpm when pulling away at an obstacle. 4H or 4L , auto or tip tonic , starting in 1, or 2.
Even an experienced Mitsubishi driver was surprised at lack of revs when he tried same obstacles.

Had her in for a service two weeks back. Agent says he check for codes and found none. Did reset.
Still , 22 hours in one week on a recent trip to Durbs and back from P.E I struggled with 2 nd gear lack of oomph when needed most : to pass trucks etc on inclines from 30 or 40km/ h. Refuses to rev above 2200rpm. She just holds at 2200 and 'slips' the converter till she's in 3 rd.
TOTALLY different story from 80 km/h in 3rd, pulls like a train, will rev to 4200 and holds 3rd until 150km/h if asked.

Tip tonic does not fool the arrangement either.
Still Slips and slides from 2nd to 3rd if not pushed

Maybe Mitsubishi trying to protect the box from too much torque?

However, looking through the shop manual troubleshooting methods for the other box(5 speed), I see lots of reference to the Accelerator Position Sensor. Seems that can confuse things too.
I wonder...?

Sorry for a stupid question. Have anyone checked the fuel filter? I had a Jetta 4 TDi doing alost the same. Dealer said it could not be the filter as it was replaced on prev service. After a LOOOONNGGG trail & error seeking (and costly) by the dealer, I suggested replacing the filter out of desperation. Voila, problem solved.

PS I've never gone back to that dealer.

Good point.

Can only hope that the filter has been changed at one of the 7 services at agent.
We at 73 000km now.
Will add to checklist though.