206 Gti Hdi Low Power

[Cloverleaf 1]

As above, my gf's car suddenly lost power while crusing on the motorway. No lights on the dash or anything.

 

It still revs normally but it doesn't have any power. Limped it to my mate's garage and then "anti pollution fault" came up on the dash for a bit but then disappeared.

 

The only relevant fault code was "low boost pressure" - obvious (due to the lack of power and the pipes don't firm up under throttle), but not much help.

 

There's no obvious leaks in any of the boost pipes, actuator shaft seems free to move, turbo spins freely. I'm really stuck

 

Any help greatly received!!

 

Thanks,

 

Joe

[welshpug 1,657]

Have a look at the live readings, could be a faulty MAF or TPS.

[Cloverleaf 1]

Would that not bring up a fault code?

 

I'm not sure what diagnostic reader my mate has, I'm not sure it gives limits - do you know what these readings should be?

[Tom Fenton 1,541]

It is not actual discrete numbers you are looking for, more that the numbers change while driving in the way you would expect them to, indicating the sensor in question is healthy.

[Cloverleaf 1]

Ah OK.

 

I don't suppose you know what happens in this manifold and what each of the sensors are?! (Is the MAF one of these?)

 

[welshpug 1,657]

I don't know that engine too well but there's a map sensor there on the way to the intercooler, the MAF is on the air filter box outlet directly typically.

[Cloverleaf 1]

It seems no one really knows this engine very well!! Can't find much out about it on the net and I've never played about with it. It's a daily so I can't really take it off the road.

 

It almost looks like some kind of intercooler bypass...not sure what goes on in there.

 

Thanks for your help.

[dcc 855]

boost leak?

[pugdamo 111 2 Cars]

Your right that valve is an intercooler bypass valve.

Iv done a bit with these engine and iv got a 1.6 focus in at the mo (same engine) with the same fault,these engines are VERY prone to turbos.I always pull the rubber pipe off to the turbo and check the turbine,but the focus i had felt ok,i used a mityvac on the turbo actuator and took it up the road actuating the turbo myself,still no boost,removed the turbo to find that the shaft had snapped.

If yours is a turbo you will need to ring a dealer for the list of parts you need to replace,the only way you can get a warranty on the turbo is to replace everything that comes into contact with oil.

I dont want to be the spreader of doom and gloom and it might not even be this but it really isnt a cheap job,unless you fit just the turbo and sell it quick.

Edited January 20, 2013 by pugdamo

[Cloverleaf 1]

I'd hoped it was a boost leak but if it is its not obvious...like they normally are.

 

The turbo seems ok. I took the inlet pipe to the compressor off and it felt alright (and span up with the engine running). So I dont think it can have a snapped shaft.

[pugdamo 111 2 Cars]

Thats ok then,if you could get hold of a mityvac that is a quick and easy test to check that the turbo is capable of delivering boost,if you get boost then it could be the solenoid valve thats failed or a split vacuum pipe to the solenoid valve or from that to the turbo actuator somewhere

[ablister 31]

as above, check the vacuum pipes to the turbo solenoid, have seen them split before

[sickomotorsport 4 2 Cars]

these can block cats, I would check this first, remove it and shake it and you will hear it if it's blocked.

[Willem_Jacobs 6 1 Cars]

And if it has an sooth filter fitted (not sure if that's the right translation dutch>eng) wich is fitted somewhere after the cat. this can also be blocked.... Just try and get it off and use a regular waterjet-cleaner to remove some of the sooth to unblock it....

These filters are actually designed to fill up with sooth, and there's a second lambda sensor fitted in some cases to check if this system is working, if not it will go into limp-home mode...

I've also heard of leaking boost-hoses (leading to the intercooler) this will also result in some serious loss of power, and the anti-pollution fault... It's either part of the intake system (leaking) or the (sensors in) the exhaust !