Puma lack of power

[Peaklander]

Hi all

A mate has a 61 plate 2.4 Puma swb and tootles about in it pulling a small trailer. Recently though he needed to tow a heavy load. This was a double axle trailer with very long steel and ali poles. Now he says it was heavy but I don't think it was a heavy as more typical loads such as @reb78 towing his Disco or @Arjan towing massive roof parts!

On a very long drive he was unable to reach any sort of cruising speed on the motorway. I think 30mph was the maximum. When he told me I was only able to say that it must be some sort of turbo boost issue that might have been there for the twelve months he's has the vehicle, only becoming apparent with a proper load to pull.

I called in at a local garage and the disconnected the waste-gate and checked it operates. It was stiff but I can't find out if it was stuck open or not.

For some reason he is hesitating taking it to a dealer but I don't know anything about these engines. Can I ask a few questions?

1. Do diagnostics reveal the cause of issues like this?

2. Is turbo boost pressure controlled by an ecu and therefore is the waste-gate also control-led by electronics?

3. Is the FIP also ecu controlled rather than receiving a boost signal from air pressure as on my 300TDi.

4. Would a boost gauge show really what's happening and if so what sort of input would one use? Presumably there's still a boost pressure that can be tapped into?

 

Thanks guys for any help and yes, I think he should probably take it to a LR specialist.

[Arjan]

Without seeing the vehicle etc. there is only one thing to suggest and that is going to a specialist and have it talk to a computer.

 

[Tanuki]

My first step would be to get it to someone with a code-reader and see what faults are logged. 20 quid spent on this can save a lot of time and money over randomly replacing parts in the hope of fixing the fault.


There is no "FIP" as such on a Puma - it's a "common rail" Diesel with each injector fired individually under ECU control.


The timing and duration of the firing being controlled by the ECU which takes into account things like throttle position, engine temperature, Manifold Air Pressure [same as boost level] and Mass Air Flow [volume of air being sucked in]. These engines don't have a "wastegate" as such, they use a variable-geometry turbo nozzle controlled by the ECU.


Buggering about fitting a temporary boost gauge is a lot of effort to go to when you can read the boost-pressure electronically.


You say it's only ever been driven gently for a year or so - my suspicion would be either that the VNT has stuck in the 'low boost' position [same as wastegate stuck open] or that the Diesel Particulate Filter [DPF] that sits immediately below the turbo in the exhaust-pipe has become clogged with soot and is restricting exhaust flow. DPF blockage is a well-known and common problem on Transits which share the Puma engine. "DPF Differential pressure too high" being the symptomatic fault code. If it's not *too* bunged-up they can sometimes be 'regenerated' by way of an ~Italian Tune-Up~ where you drive down the motorway at full-throttle at 60 in 3rd gear with the engine running on the limiter for 10 minutes or so! if not, the DPF can need replacing [not uncommon in vehicles only driven gently].

Edited September 17, 2017 by Tanuki

[Peaklander]

Tanuki that's a great help, thanks. He'd said that he had seen the local garage remove a clip and check movement of something - and he had done the same later too. I thought it would be some mechanical actuator hence the wastegate reference.

So we are talking about a vnt - I can at least read-up on that for interest.

I'll go and see him and explain your advice. 

[Thon]

On 9/17/2017 at 10:26 AM, Tanuki said:

You say it's only ever been driven gently for a year or so - my suspicion would be either that the VNT has stuck in the 'low boost' position [same as wastegate stuck open] or that the Diesel Particulate Filter [DPF] that sits immediately below the turbo in the exhaust-pipe has become clogged with soot and is restricting exhaust flow. DPF blockage is a well-known and common problem on Transits which share the Puma engine. "DPF Differential pressure too high" being the symptomatic fault code. If it's not *too* bunged-up they can sometimes be 'regenerated' by way of an ~Italian Tune-Up~ where you drive down the motorway at full-throttle at 60 in 3rd gear with the engine running on the limiter for 10 minutes or so! if not, the DPF can need replacing [not uncommon in vehicles only driven gently].

I don't believe any of the 2.4 Pumas were fitted with a DPF - I think it was only fitted on the 2.2s. VNT certainly an option, and probably a myriad of other things too ...

Edited September 24, 2017 by Thon
Incompetence.