Power Questions

[pos]

Good evening,

For those of you who haven't seen my thread in the newbie section, I would just like to say hello! I am the happy owner of a 1995 KZN130, which replaced my 300tdi 110.

I have had a read through some of the material on the site and it is all exceptionally useful but I still have a couple of questions which I am hoping someone may be able to shed a little light on.

First things first...

On a recent trip to Guernsey from Leeds, my Surf was pulling like a train until I noticed at one point that it seemed particularly limp. It started loosing momentum and the throttle had no effect, with revs sitting at about 2500. I was crushing at around 75mph, with the temperature gauge sat at about 1/4. I noticed the temperature started to increase to just over 1/2 so I let it hang around 60mph until it cooled and then everything seemed to pull fine again.

When I got to Guernsey, I swapped the radiator cap, changed the fuel & air filters and also checked the vacuum pipe between the boost pressure sensor and the intake manifold. Cleaned the little filter out too so all seemed good.

On the way back from Guernsey the same thing happened again, only this time when sat at 75MPH, I noticed a sudden loss in power as if a boost pipe had failed but with no overheating. Pressing the accelerator again had no effect and the revs were stuck at around 2500. When I stopped, the vacuum hose from the boost pressure sensor had popped off, so I re-connected and the Surf pulled like a train again, even up big hills with absolutely no loss of acceleration.

Now however, the problem seems to have reoccurred. The boost pressure sensor tubing has been replaced, the small filter has been cleaned and there are no obvious issues. The problem is that it just doesn't want to pull up hills as well as it sometimes does. Once the torque converter locks up at about 55-60, it will not accelerate beyond 2500 revs and pull up the hill, meaning I slow down. If I press the throttle to the floor, the gearbox kicks down but then the engine is revving outside its power band and it doesn't pull away.

Is there anything else I can check? Any sensors / vacuum lines that could also cause this issue?

Thanks in advance for any help

-Tom

[woodwarm]

Hi Tom

Have you checked for fault codes?

If no code disconnect battery (or both) 1/2 hour or overnight to reset ecu.

Robert

[tashtego]

Welcome!
Have you checked the ATF level and colour?

[pos]

Hi Tom

Have you checked for fault codes?

If no code disconnect battery (or both) 1/2 hour or overnight to reset ecu.

Robert

Hi Robert,

I haven't as yet. Am I right in thinking that the Check engine light will flash if there are any fault codes present, or is that not always the case?

Thanks,

-Tom

[pos]

Welcome!
Have you checked the ATF level and colour?

I checked the ATF level about a month ago and it did require topping up maybe 500ml although it is still relatively red in colour. I checked with the engine hot and idling. There does appear to be a slight ATF leak somewhere around the auto box and the box does seem to make a rattly / hydraulic sound when in 'D' but sat stationary. Putting the box into 'N' or 'P' stops the noise. Also, when first setting off from cold, I can hear only what I can describe as a fluid transfer sort of sound when accelerating or when blipping the throttle with the box in 'D'. I'm sure this is related to the gearbox and it is definitely a new sound.

I should also mention that at certain throttle positions regardless of engine speed / load, there seems to be an electronic high pitch buzz that I can hear which stops as the throttle is lifted or pressed further down. I'm sure the sound is coming from the footwell / drivers side of the engine bay although I am not sure if this is related.

Thanks,

-Tom

[woodwarm]

My 2.4 had fault codes stored in ecu, no check light on.

Not sure about 3litre.
Someone more modern be along soon



Re your further post auto box noise. Think you've found the problem

[pos]

My 2.4 had fault codes stored in ecu, no check light on.

Not sure about 3litre.
Someone more modern be along soon



Re your further post auto box noise. Think you've found the problem

Hmm, I will give it a check then. I guess an ATF and gearbox oil filter change is a good idea although I can't believe there isn't a drain plug on the sump! Surely if the gearbox were at fault I'd be seeing the overdrive light flashing on the dash? Soo many electrickery bits and bobs!

Cheers,

-Tom

[woodwarm]

Search for "atf drain"

lots of info/advice


Auto box filter is a strainer in sump. Clean if you feel it's required.

[Dobbslc]

The fluid transfer sound you mention might be air in the coolant running through the heater matrix behind the dash board.
You could have an air lock and that would cause the overheating.

Try it from cold with the heater turned off then turn heating on and you will hear bubbles if that's your problem.

[pos]

Search for "atf drain"

lots of info/advice


Auto box filter is a strainer in sump. Clean if you feel it's required.

Have just read through a few topics, thank you!

[pos]

The fluid transfer sound you mention might be air in the coolant running through the heater matrix behind the dash board.
You could have an air lock and that would cause the overheating.

Try it from cold with the heater turned off then turn heating on and you will hear bubbles if that's your problem.

I will try that in the morning,

Thanks,

-Tom

[Bogus]

Hmm, I can't believe there isn't a drain plug on the sump!

-Tom

There is.