Boost leak, lack of octane or just knackered?

[Rusty]

Have been trouble shooting quite a bit over the last few weeks. Managed to clean the MAF twice. Removed, cleaned, checked and refitted every turbo hose I could get my hands on and have had the ECU read, which was clear of faults.

However, even though she's running better there are still occasions when the power deliver seems to surge as if the boost is fluctuating and what I'm guessing is the overboost protection (brakes on kind of thing!) cuts in at really inopportune moments, like overtaking today! (Car was absolutely flying one minute and then at full load in 5th it decided to cut out whilst coming up to the end of a dual carridge-way... D'OH!)

Seems to be random but mainly once warm and under full load, with the effect being worse in the warm weather (hence idea 3 below).

I have come up with the following ideas.

1) There is a turbo boost leak due to a hose or the intercooler.

2) An ancillary is on the blink but has not flagged up a fault code yet (highly unlikely?).

3) I've not got enough octane from the Optimax to cope with the overboost and the knock sensor is cutting in.

If there is anyone in the Bristol area who has the equipment to find a boost leak then their help would be much appreciated as it may onlybe under full boost that the leak is occuring and the heat is softening the rubber hoses? Any other help would be equally gratefully received.

I'm hoping to get it rolling roaded in the near future to check power and torque figures against standard so this may flag up any problems. Thinking AmD... thoughts???

Cheers, as always

Andy

[Jas11n]

Have been trouble shooting quite a bit over the last few weeks. Managed to clean the MAF twice. Removed, cleaned, checked and refitted every turbo hose I could get my hands on and have had the ECU read, which was clear of faults.

However, even though she's running better there are still occasions when the power deliver seems to surge as if the boost is fluctuating and what I'm guessing is the overboost protection (brakes on kind of thing!) cuts in at really inopportune moments, like overtaking today! (Car was absolutely flying one minute and then at full load in 5th it decided to cut out whilst coming up to the end of a dual carridge-way... D'OH!)

Seems to be random but mainly once warm and under full load, with the effect being worse in the warm weather (hence idea 3 below).

I have come up with the following ideas.

1) There is a turbo boost leak due to a hose or the intercooler.

2) An ancillary is on the blink but has not flagged up a fault code yet (highly unlikely?).

3) I've not got enough octane from the Optimax to cope with the overboost and the knock sensor is cutting in.

If there is anyone in the Bristol area who has the equipment to find a boost leak then their help would be much appreciated as it may onlybe under full boost that the leak is occuring and the heat is softening the rubber hoses? Any other help would be equally gratefully received.

I'm hoping to get it rolling roaded in the near future to check power and torque figures against standard so this may flag up any problems. Thinking AmD... thoughts???

Cheers, as always

Andy

IC o-ring???? try a search for the Mark H mod

[pjeast73]

I'm not saying this is the problem, but I had boost leaks coming from the intercooler itself. Tiny holes were in it. Could quite easily hear and find them when the system was pressure tested. Fixed these - but problems was only sorted when a new MAF was fitted.