Gearbox not shifting properly

[nobber]

Dear all,

I have recently been having issues with our auto gearbox shifting correctly, when cold it performs fine but once warmed up it will change but only at 4000+rpm or if you de-accelerate and then it lurches into the next gear, once in top gear and cruising it now tends to kick down on any kind of incline.

this is intermittent but 85% of the time is like this, we have recently had the Rad and the fuel sensor earth replaced, it started soon after this, it went back to the garage for a service and to investigate this problem, the gearbox fluid was leaking and empty, this was repaired and new fluid was put in (this did not improve the shifting), this is still fully toped up, but we were advised that there was a small diesel leak causing the turbo to not work correctly, could any of this be related?

Thanks

Julian.

[Alacrity]

If the engine is down on power then you can have late shifting due to the fact you have to put your foot down further to get the same vehicle performance. The transmission ECU thinks you want to go faster because your foot is down so it shifts the transmission later. I would think you would notice the poor performance though (though plenty of Mercedes owners don't when their MAF sensor fails ). If the diesel leak isn't enough to effect overall performance then I would expect you to have a TPS problem, the TPS (throttle position sensor) sends the signal to the trans ECU as to (as its name implies) how much throttle is being used.

[nobber]

No the engine seems to have plenty of power, although you wouldn't know it as when you need it the gearbox kicks down so it all revs and no speed, I have spoken to the garage and the leak is from the fuel pump this is very minimal and require new seals so a non related issue.

I will look into the TPS sensor, thanks.

[mikeonb4c]

small diesel leak causing the turbo to not work correctly

Never heard that tale before from any others with (the usual) small leak from the diesel pump area. And if hte turbo wasn't working properly then you'd think you'd have to be down on power (but you aren't ).

Do these guys know their Bongos or are they just winging it?

There is a good Bongo mechanic in South Croydon if you can limp that far. Maybe get their name off the recommended list in members area and give 'em a call?

[dandywarhol]

If it isn't the TPS I'd have the gearbox sump dropped and the metal filter cleaned out

[nobber]

small diesel leak causing the turbo to not work correctly

Never heard that tale before from any others with (the usual) small leak from the diesel pump area. And if hte turbo wasn't working properly then you'd think you'd have to be down on power (but you aren't ).

Do these guys know their Bongos or are they just winging it?:

That comment was incorrect, Chinese whisper between the garage and my wife, the leak is just that and the turbo seems fine! the Garage is 'County Cars' in Portslade and have been very good so far, but I am trying to pre empt the problem.

[Alacrity]

I bought my first Bongo from them. I shall not comment further on an open forum.

I am just down the road from you in Hailsham, just north of Eastbourne & would be happy to look at your Bongo for you - at least I will be able to confirm any gearbox issues or not. Mind you I would think you are not going anywhere far with the coolant leak, that needs sorting before you drive it. Remember all the wise words here regarding bleeding the cooling system correctly, it is so critical on these beasts. I will send you a PM.

[nobber]

I bought my first Bongo from them. I shall not comment further on an open forum.

I am just down the road from you in Hailsham, just north of Eastbourne & would be happy to look at your Bongo for you - at least I will be able to confirm any gearbox issues or not. Mind you I would think you are not going anywhere far with the coolant leak, that needs sorting before you drive it. Remember all the wise words here regarding bleeding the cooling system correctly, it is so critical on these beasts. I will send you a PM.

it is a fuel leak not coolant thankfully, I have good experience of the perils of leaking cooling systems