flat spot on motorway

[davegolfturbo]

hi im pretty new with golfs but i have a mk 4 gttdi 115 bhp, anyway i was on a drive down the motorway and ther car was running fine then all of a sudden i just lost all power to the car as if the turbo was gone..so i pulled up on hard shoulder stopped the car, popped the bonnet to check the turbo was still spinning up. The turbo was still working pressurising the pipe, so i got in the car again turned engine on and it carried on fine...wat was the problem, any ideas?? cos i was a bit baffled lol.

thanks dave.

[Rhyso]

limp mode.

most likely a split pipe somewhere.  the air escapes and you lose pressure hence why lack of power!

check all hoses and connections for signs of a split and replace accordingly

[davegolfturbo]

ye but it now runs fine so it cant be that or the loss of power wudf be permenant shurely? ta for post dave.

[Rhyso]

not necessarily; the problem can be intermittent 

otherwise it could be MAF  check your hoses and connections first as they are a bit cheaper to replace 

[richandhazel]

More than likely it will be one of the small 1/4" dia hoses that has a leak. You'll have to methodically check them all. I would start around the boost valve (N75) located in the N/S bulkhead area.

Mine used to do it if I accelerated hard after a long run. Switch off the ignition, start up and all would be fine. As Rhyso says, it goes into limp mode where the turbo stops working.

Let us know how you get on. If you don't find anything it may be worth cleaning the N75 valve. I can find some blurb on it all somewhere if need be.

[davegolfturbo]

hey thanks fopr the advise il look into it this week sometime been bit busy with work n that how i find out which pipe is what and which ones to check as i am not familiar with the gt tdi engine or anything to do with the golfs unfortunatley. its not done it since but saying that i ahvent been for a long motorway drive. It did deffinetely seem to stop spooling up tho as you mentioned go into limp mode. thanks again dave