Can anyone work this one out?? Stalling issues!

[Craig!]

Right if i'm driving along and dip the clutch the rev's seem to drop off pretty fast, sometime the rev's will drop to 500rpm and then raise back up, others they will just drop right off to nothing. For example, driving along in 3rd, dip and hold the clutch down the rev's will just drop down to 500rpm then below and the car will stall.

Sometimes the revv's will hold on, however if your bringing the car up to spooling point, dip and hold the clutch the car will stall.

The only fault I have on VAG-COM is a 'Lambda Sensor - Circuit Malfunction' error, it is an error on the first pre-CAT lambda could this be causing these issues?

The only things I have done recently is change the plugs for NGK PFR6Q's and also replaced the rear post-CAT lambda. I didn't check the gapping on the plugs, however with genuine Audi supplied plugs didn't think I'd have to.

Any help / suggestions is a hugh stress relife for me, feel like giving up! Gone from a year of faultless driving to a week from hell and I feel I may be to blame for it as I've just recently cleaned the engine bay!

 

[Daz_gibbo]

Air leak?
Whats it like at idle?

 

[Craig!]

Idle and start up seem fine, and the N75 duty maxed out at 95.3% which is what it normally reads at. Going to check all the silicone vaccume lines, aswell as the DV/TIP connections later.

 

[cordobabrendy]

95.3 max (when running balls out foot to the floor you mean?) idle should be 0.
Have you got a boost gauge fitted, if so whats it like at idle?

 

[Craig!]

Yeh 95.3% was flat out at WOT. Every contact in the engine bay has been un-plugged and squirted with WD40 a few days ago.

 

[claudefrog]

is it the clutch pedal switch?

 

[h17och]

ive had the same problem for about 6months, drives me mad!

no idea what it is

started to happen after i put my polished manifold on :s

If you pull up somewhere, all your mate think you have stlled it! nt gd!

HoocH

 

[Craig!]

Hmm sounds likes it's throttle body related then, either the connection to the switches or it needs a clean. I've already re-alinged it in VAG-COM so know its not that.

And it doesnt do it if you slow down steadily, just if you keep the clutch in when gear changing.

 

[Craig!]

Right here's some key points and values to help diagnoses;

- If i'm driving sensibly, holding a constant speed and press and hold the clutch the rev's drop to tick over as it should

- If i'm building the car up to boost (gentle or hard) and press the clutch down just before boost comes in the rev's are quick to drop off and the engine will stall.

- The N75 values at tick over are 0.0% and at WOT in 3rd it's 95.3%.

- The MAF in third not on a power run but in a sprinting manor still produced 150.2mg/s, and I dare say if I do a power run i'll see the usual 160mg/s.

Now it may just be me, but I thought the car smelt of fumes a bit more than normal on tick over and just after general running. So this leads me to thnk the fueling is to blame... in which case it may be down to the current lambda.

I'm going to go to SEAT tomorrow and pick up the pre-CAT sensor, fit it, run the car then re-scan the car for errors. If I still get the circuit malfunction error after replacing both sensors I will then proceed to smashing the f*ck out of the car.

 

[bucky boy]

i had that when i first got my cupra an it was the peeps that had it before had fitted an atmosphertic valve.

 

[Jonzy]

PhilW used to suffer with stalling when doing low speed manouvers, I think it turned out to be the location of the DV. Hes got a spamco mk4 tip and the DV is too close to the maf.

 

[h17och]

but ive got a relocation kit!!

i may try another throttle body (once my car is running again that is!)

im getting a new inlet to head and a throttle body to linlet manifold gasket and see how it is then!

together...we can sort this problem, once and for all!! lol

HoocH

 

[Jonzy]

but ive got a relocation kit!!

So did PhilW

 

[bucky boy]

A quick quetion mate so by fitting a samco TiP some peeps are experiecing probs like stalling just asking as am in the process of getting one.

 

[h17och]

i had a tip for about 8 months before this

 

[PhilW]

As jonzy said. ONLY the old skool MK4 Golf Samco TIP. NOT the forge one for the Ibiza.


Its basically venting too close to the MAF.

Unplug the maf and see if it stalls then.



I used to get it all the time when parking quickly or on a hill comin off the gas when on load.

Done it once in the dark doin 60mph on a mountain road. Not funny losing full beam, brakes and steering.

 

[David_smith_909]

A quick quetion mate so by fitting a samco TiP some peeps are experiecing probs like stalling just asking as am in the process of getting one.

mk4 golf tip he is on about mate

EDIT: too slow

 

[h17och]

what about a 225 tip then?

 

[David_smith_909]

what about a 225 tip then?

good point , iv got one on the way to me, would also like to know if this one will have issues, shouldnt do, just checking, not heard of any problems with this tip

 

[h17och]

im guessing it wont as the take off for the dv is lower down!

What turbo are you fitting then mate?

HoocH