Ok starting to get worried now...

[Chris 16v]

A few of you may remember a few months back when i first got my LC i complained of a serious lag sometimes when accelerating hard and changing rapidly into 2nd.

Now this has got worse, much worse and happened when trying to overtake going from 2nd to 3rd and nearly killed me.

Scenario is:

Accelerating hard in 2nd, pull out to overtake, and changing gear at about 6k rpm.

I change into 3rd and put my foot down pretty damn hard. At this point the engine revs but nothing and i mean nothing happens. If you are in the car you fall forward in the seat belt and expect it to come on boost but nothing, this enormous lag lasts in excess of 3-4 seconds and then it will suddenly kick in.

The engine sounds like its sucked in water almost, bit of a gargling noise.

It was fecking dangerous when i pulled out and it lagged so much the guy i was overtaking started undertaking me!

Any advice appreciated.

Cheers

Chris

 

[Ruddmeister]

Swap the dump valve with someone else if possible, could well be the DV.

I had similar symptoms

 

[RobM]

N75 could be another possible cause? Although I doubt that would explain the noise....

Do you know anybody with a spare DV that you could try? Where in the country are you?

 

[Chris 16v]

I live in Worcester 25 miles away from Birmingham, but work in brum. Not too sure what to do tbh, would it be worth buying a replacement forge jobby? N75 - is this the maf sensor? Sorry, im learning as fast as possible!

 

[toledoChris]

It sounds like a Maf sensor on its way.

 

[The MoffMeister]

n75 controls the maf if im correct!!

 

[Big_daddy]

get it check on a diagnostic, this will show any faults. wheat revs do the car jam up on?

 

[Chris 16v]

In all honesty i dont know as im not watching the revs so much as panicking about staying alive - im pretty sure its a change from about 6krpm so about the 5k mark??

I have no access to a diagnostic machine, would the audi one work the same as my mate runs an audi servicing dept lol

What are the common symptoms for sump valve, N75 and maf sensor failure?!?!

Cheers

Chris

 

[Big_daddy]

yeh had similer problem wer the car freeze at 5000rpm, caused by fault N75 valve (bost pressure valve).

 

[Chris 16v]

interesting, how much to replace it??

 

[Ruddmeister]

n75 controls the maf if im correct!!

No the MAF just reads the volume of air being sucked in so the ECU can calculate fuelling

The N75 is an electronic solenoid valve that the ECU uses to control boost, connects to the wastegate.

get it check on a diagnostic, this will show any faults. wheat revs do the car jam up on?

Good advice find yourself a specialist or someone local with VAG COM or similar, or just get it to a dealer

Chris It sounds like a Maf sensor on its way.

When MAF has expired on my car (2 occassions) it didn't have the hesitation/lag Chris described.

The misreading MAF meant full power all the time or Limp, not jumping between the two

My money is still on the DV but Fault diagnosis is the way forward unless you can find someone to swap DV's with (as they take 10mins to change should be easy enough to do)

Chris - change one thing at a time and test otherwise you'll end up chasing your tail and never finding the fault, plus it'll cost you a packet

 

[Big_daddy]

interesting, how much to replace it??

from dealers its around £60,

from http://vagparts.co.uk/

 

[Ruddmeister]

You can also leak test the DV yourself without a replacement

To test if your DV has failed remove the DV, press the diaphragm up, put your thumb on the top nipple, and then release the diaphragm. There should be suction created on the top of the DV that prevents the diaphragm from returning. If there is no suction then the diaphragm is leaking and the valve should be replaced.

IF the valve is good, check the VAC line leading up to the valve for any cut’s/ tears.

More details on the Forge Website and diagrams etc.

Chris - As you can tell a lot of this stuff is guess work you really need your fault codes read.

 

[Big_daddy]

if i was u, i jus will change dv any to forge, the last longer and improve trottle response, good 4 overtaking. lol

 

[andycupra]

my thoughts would be, in this order:

DV (diverter valve)
loose pipe / collapsing pipe
N75

i cant see it being the maf.

 

[P-torque.co.uk]

If you want me to have a look at it for you, bring it in and we'll see what we can do.

 

[daniel_owen_uk]

Sounds like the clutch slipping to me, if it revs but doesn't move, we can talk about DV, Loose pipes, N75 and MAF as much as you like, but it's getting power, just not applying it to the wheels.

I change into 3rd and put my foot down pretty damn hard. At this point the engine revs but nothing and i mean nothing happens.

 

[Chris 16v]

hmm now i think about it im not sure if the revs do go up, ill wait until it happens again, the engines sounds like its suffocating rather than clutch slip.

Its only done 28k


Power Torque - are you a seat specialist or dealer or what? i need a 30 k service done next month and would rather not go to a dealer as i simply dont trust them!

 

[Big_daddy]

hmm now i think about it im not sure if the revs do go up, ill wait until it happens again, the engines sounds like its suffocating rather than clutch slip.

Its only done 28k


Power Torque - are you a seat specialist or dealer or what? i need a 30 k service done next month and would rather not go to a dealer as i simply dont trust them!

well if u around birmingham, i cud give free vag scan! if u r around

 

[P-torque.co.uk]

hmm now i think about it im not sure if the revs do go up, ill wait until it happens again, the engines sounds like its suffocating rather than clutch slip.

Its only done 28k


Power Torque - are you a seat specialist or dealer or what? i need a 30 k service done next month and would rather not go to a dealer as i simply dont trust them!

Hi

We are specialists in all VAG tuning.

We also work closely with a VAG servicing specialist who would do a superb job on you car.