Hi, I have a question and I think I know the answer but I'd like an opinion before I do anything :-)

I was driving to work this morning and everything was normal - I accelerated slightly, not much boost if any, and I felt a slight loss of power. It felt like a step function or as if I'd let off the gas abruptly.

Didn't think much of it as the engine was still a little cold.

A few miles further along when the engine was fully warmed up I went WoT and noticed the engine had lost it's 'punch'.

The boost which would normally come on hard at anything above 2500rpm was only managing to hit 0.5 Bar by about 4500rpm - normally it'd be approaching 1.0 Bar. Engine runs smooth as ever at higher RPM's - just takes longer to get there.

Engine runs fine otherwise, no check engine lights (at least not yet).

So I'm thinking an air leak somewhere - don't think it's the plugs or MAF.

Any thoughts or suggestions before I take a look ?

Any suggestions on how to find where the leak is - assuming there is one ?

FYI car is still under warranty, but has a few mods so might have to de-mod it if it turns out to be something serious.

 

I think your car went into limp mode. Disconnect the battery for a few minutes and it should reset. Make sure you have your radio/nav codes handy.

 

LImp mode for sure. disconect the battery for 5 minutes...

 

Hi Guys,

Wow that was fast and thanks for that tip - I'd forgotten all about 'limp mode'.

Certainly worth a try before delving in any further :-)

If it were a boost leak, I'm wondering what the symptons would be ?
No boost or very little boost at all ? Poor A/F ratio ?

I have an OBDII scanner / logger at home - I think I'll log a few vital parameters before performing a reset.

BTW even though it was in 'limp mode' sure wasn't slow - just didn't have that pin you in your seat feeling under WoT.

Felt a little like when I blew a head gasket on a 3.0CSL BMW I once owned a long long time ago now !

Thanks again - Tim

 

Pardon my ignorance but what is a limp node ? When does it happen ?

 

wet noodle?

 

disconnected the battery for 5 mins and all is well again - back to 'warp' speed.

Seemed even faster than before !

Didn't have to re-enter any code in the radio / cd player.

Question now is why did it happen ?

I'll do an OBDII scan this evening to see if there were any codes set.

Thanks guys - I appreciate your help and advise.