No Boost :(

[col666]

have had a few with ECU problems,i take it after plugging in the select monitor that the boost pressure registered is the same as you are quoting,cat collapse a few times and(i hate to say it) the 2.5 problem ring land,all of the knackered engines have had no power but have driven fine,have you noticed any 'blue puffs' on cold start.The symptoms sound exactly the same as the many 'piston problem' cars we have had and had to rebuild.

Gav

I mentioned to one of the salesmen today that there were rumours that the 2.5 had chocolate pistons but he denied any knowledge of it...as you would!

[Big 'D']

Just had another thought could a faulty MAP sensor limit power output perhaps restricting the engine not the turbo?

Cheers Iain

[thewelsho]

I mentioned to one of the salesmen today that there were rumours that the 2.5 had chocolate pistons but he denied any knowledge of it...as you would!

Oh! But they ARE chocolate! I have one with a big chunk out of the ring-land (as Gav says). I can't see how a damaged piston would prevent boost though. My car hit boost with the damaged piston, but when it got there, the ECU retarded the timing as it did at high revs in every gear. Actaully, the car was worse in low revs in low gears.

Edited August 13, 2009 by TheWelsho

[Big 'D']

Oh! But they ARE chocolate! I have one with a big chunk out of the ring-land. I can't see how a damaged piston would prevent boost though. My car hit boost with the damaged piston, but when it got there, the ECU retarded the timing as it did at high revs in every gear.

I have to agree here, there would have to be a huge loss of compression for there to be less than wastegate pressure produced on a boost run, also I guess that this would also be visible like mentioned before as blue smoke or rough running in extreme cases, was the 2 psi figure taken whilst the car was on the road under load?

A very odd one this but like mentioned already I bet its something really stupid and easy (fingers are crossed).

Could be a fuelling issue I suppose restricting the engine output not actually the turbo at all? (blocked fuel filter/poor pump output)

Cheers Iain

[col666]

A new MAF sensor was fitted and made no difference.

The 2psi boost reading was taken on the road.

[Big 'D']

A new MAF sensor was fitted and made no difference.

The 2psi boost reading was taken on the road.

Has the MAP (Not the MAF) sensor been checked?

If the car is starting (no smoke), idling ok, reving ok in neutral and just has no power/boost on the move, I think we have pretty much exhausted all of the possible options, its either the engine is not getting the fuel/air to produce the exhaust gas to drive the turbo, the turbo or wastegate itself is goosed, or there is a restriction somewhere.

Cheers Iain

[col666]

Well after having the car for 10 days they have eventually found out what has happened. After telling me last week the Cat was fine it now turns out its not, there is a blockage and due to the heat build up or maybe debris the turbo has also gone awol and cracked!

[thewelsho]

Well after having the car for 10 days they have eventually found out what has happened. After telling me last week the Cat was fine it now turns out its not, there is a blockage and due to the heat build up or maybe debris the turbo has also gone awol and cracked!

How can you not see that! Well at least you have got to the bottom of your troubles and the end is in sight.

[col666]

How can you not see that! Well at least you have got to the bottom of your troubles and the end is in sight.

This is just the start of my troubles......to be continued....!

[dipsy]

Col is it the three digits in your user name giving you car problems