[hz2921]

Hi Guys , for a few months now , when i start my car and drive off normally, the engine seems to speed up or pull more for about 1-2 seconds, this causes the car to lurch forward, then it slows down again?, it only happens in slow speed, not when youre doing above 15-20 mph, what could be causing this?, could it be the wastegate valve on the turbo is sticking?, so it opens to allow more boost , but it sticks when trying to close, ie which is what is causing the engine to lurch forward?, it also happened when i drove off fast in 1st gear, the engine slowed down, then picked up again straight away, to my brother it looked as though i had slowed the car with the brakes momentarily before speeding off again, someone please help!!!!.

Thanks Zak

 

[mattbecker]

This sounds exactly the same as my car which I cannot seem to fix my car surges under acceleration and is especially bad when cold. I have replaced MAF no better, have yet to change spark plugs as it could be a light missfire. I have bought a N75J valve to see if it helps, will fit tonight and let you know

 

[EddyH]

Sounds like a sticky N75 or DV. Check the N75 for dirt and check the operation of the DV.

 

[hz2921]

Eddy, ive changed my n75 valve for a new one, and ive recently put a forge dv007 recirculating valve on as well, i,ll take it to Pj, to see what comes up under vagcom.

 

[EddyH]

Was the DV007 new or used? I know of someone that had one fail recently and they had similar symptoms to yours. Even if it's new I'd check the operation of the DV as per the instructions on the Forge site.

Would be good if you could log spec boost and actual boost when the problem occurs. If actual exceeds spec by a fair margin then it would suggest something is sticking.

 

[hz2921]

how shall i log the boost?, oh yeah, ive got a brand new forge valve.

 

[rich1068]

Quote: posted by EddyH on 15/02/2005 16:56:20 I know of someone that had one fail recently and they had similar symptoms to yours.

I guess that's me then []

Zak,

Definately check the DV. Unscrew the top and check it's clean. Also, what colour spring is inside? If it's yellow try changing to green (softer).

Does this problem show up just from cold or day to day driving?

 

[GaryM]

Green is the stock spring as supplied by Forge with the 007 DV, yellow is recommended for chipped / remapped cars.

 

[rich1068]

That's what the guy at Forge told me but mine runs so much better with green.

It's either the change of spring or the fact that my DV isn't full of filings from the top of the spring [:O]

Go figure???

 

[GaryM]

Quote: posted by rich1068 on 15/02/2005 18:57:46

That's what the guy at Forge told me but mine runs so much better with green.

It's either the change of spring or the fact that my DV isn't full of filings from the top of the spring [:O]

Go figure???

Rich, have you logged requested and actual boost values with both the green and yellow spring?

What happened to your faulty DV then?

 

[alpesh]

also check the water temp sensor, abt ?25 to replace, makes ecu think engine is cold when its not hence more fuel is pumped in and you get the surge. i had this on my 1.6

 

[EddyH]

Quote: posted by hz2921 on 15/02/2005 17:05:56

how shall i log the boost?, oh yeah, ive got a brand new forge valve.

You need to log engine measuring block 115 in VAGCOM.

 

[GaryM]

Quote: posted by alpesh on 15/02/2005 19:16:56

also check the water temp sensor, abt ?25 to replace, makes ecu think engine is cold when its not hence more fuel is pumped in and you get the surge. i had this on my 1.6

I dont get any surges when cold in my 1.8T.

 

[Y0Gi]

I got that a while back. Basically i took it to my mate at alan day vw & he gave the throttle body a good clean, seems to have done the trick altough my MAF is still waiting to be changed and im only gettin a 0-60 in 10 secs @ best [V]

YOG

 

[weeloon]

YOGi got in there 1st, I too think it could be a dirty throttle body as this is what the ecu uses to know how much air is going into the engine, which in turn tells the N75 valve when to alter boost and when the dump valve has to dump excess air.

Yes I know they have MAF & MAP sensors but the throttlebody is the last measurement before the engine and its what the ECU bases its final decision on after seeing airflow and pressure readings.

Plus its the cheapest fix if it works []

 

[hz2921]

Thanks , will clean the throttle body this week, to clean it do i just take off the inlet pipe from it and clean out any grunge or do i have to actually take the throttle body off and clean it from both sides?

 

[Y0Gi]

Quote: posted by hz2921 on 15/02/2005 23:20:47

Thanks , will clean the throttle body this week, to clean it do i just take off the inlet pipe from it and clean out any grunge or do i have to actually take the throttle body off and clean it from both sides?

erm.... Unless anyone can answer before then i'll ask my guy at VW when i hopefully (FINGERS CROSSED) go on thurs when i get my MAF changed (please please please let it happen, ive been waiting for over a month now with my slow golf)....... anyway got carried away there! I'll ask thursday.

YOGi

P.S Zak you must come to the london meet!!! Its gonna be quality!!!

YOGi

 

[turbo_gti]

My car (AUM) done the above for ages running and aftermarket DV and revo, I changed back to the TT DV and the stutter /surge was less violent, I also cleaned the TB and that sort of helped. AMD told me also to remove a metal clip which holds two pipes together which come up from the acutator, they said it had been known to restrict the boost to the N75 and create a lurch.

Wilko vag.com'd my car with no codes

 

[trl]

Did that work?

Tony

 

[Y0Gi]

My mate at VW says you dont need to remove the throttle body, just give it a good spray with carb cleaner and a wipe with a dry cloth!

P.S Got my 1.8T fixed at last!!! Turns out the intercooler hose was partly disconnected from the intercooler which meant no pressure which meant no turbo! I finnaly heard my DV for the first time since ive got the car & bloody hell shes RAPID!!!!!!

YOGi