mg maestro turbo problems.... need help please

[powerfulsteve]

hi everyone im hoping you can help me, i have a turbo which will start and run with the vent valve open but will cut out if blocked, if i rev it up with the valve open it revs up to 4000 rpm then cuts out, if i disconect the turbo pipe from intercooler it will rev up and not cut out. any ideas ....... its doing my head in and i cant work it out :banghead::banghead:

[G Force]

Hi,

I would check that both the plenuum chamber gaskets are the correct type for the turbo and not the NA type. Check that the restrictor is not blocked with bits of old gasket, (the one in the plenuum mounting flange of the carb, where the air/boost pressure enters the float chamber).

[powerfulsteve]

It hasa new gasket on it and I have serviced the carb and still no different, even changed the needle. I have tried and put a compressor on the pipe off the plenum chamber till petrol was coming out the vent valve and still np different :banghead:

[G Force]

It hasa new gasket on it and I have serviced the carb and still no different, even changed the needle. :

Hi again powerfulsteve.

I am sorry to ask this again:o If you are sure the plenuum gasket is the turbo type then fine Ill have to think of something else. It is just that if you were to use a N/A gasket they don't have the small hole in them for the float chamber to be pressurised on boost.

In picture 1 you can see the grey N/A gasket bottom left with 4 small holes.

In picture 2 the turbo type gasket is the teal coloured one under the green carb flange gasket. You can just make out it has many more holes.

I have tried and put a compressor on the
pipe off the plenum chamber till petrol was coming out the vent valve and still np different :banghead:

If a N/A gasket was fitted this would still happen, because compressor pressure would be able to reach the float chamber down the main jet and balance and idle drillings.

Cheers.:)

[powerfulsteve]

im sure its thegasket in picture two but will double check in the morning to make sure and will let you know and if you can think of anything else that would be great :giveup:

[powerfulsteve]

what does the fuel ecu do?

[G Force]

what does the fuel ecu do?

It just controls the cold start enrichment, fast idle & idle speed therafter. It has no control over boost pressure unlike the one on the Metro turbo, which only modulates boost.

[G Force]

im sure its thegasket in picture two but will double check in the morning to make sure and will let you know and if you can think of anything else that would be great :giveup:

When you have the plenuum off check that nothing is blocking the small float chamber restrictor on the intake flange of the carb. Also make sure the sandwich plate between plenuum & carb is not obstructing the float chamber port restrictor as it might be posible to fit it the wrong way round or incorrectly.

[powerfulsteve]

Just to let you know it's working now and you were right it had the wrong gasket on between the plenum chamber and mounting bracket for the cooling pipe can't believe that was the fault all along can't say thank you enough and I owe you a drink lol

[G Force]

Just to let you know it's working now and you were right it had the wrong gasket on between the plenum chamber and mounting bracket for the cooling pipe can't believe that was the fault all along can't say thank you enough and I owe you a drink lol

You're welcome mate. Really pleased that you have sorted it!:)

Have fun driving it:D

Regards, G Force.