al3xfoster
Guest
Performance issues following a VNT clean.
Hi All
Over the past couple of months my Ibiza (110bhp) had been going into limp mode more and more frequently. After searching through the forums I performed the following;
I was still getting limp mode so plugged her into VAG-Com and got a boost deviation - intermittent error. After some research I tried the VNT cycle procedure using the diagnostics and discovered the VNT actuator arm was stuck. After two days of work my turbo is now back on the car and spotless, and the VNT test shows the arm moving as normal. Also, from driving around with the diagnostics plugged in I can see that the boost parameters are correct. As are the MAF ones.
There are now no error codes on VAG-Com.
BUT
The car still doesn't feel right. There seems to be an initial spike in boost (Particularly in 2nd gear) at about 2250rpm. This spike then vanishes at around 2500rpm and I seem to loose boost (not completely) until around 3000rpm. Then the car pulls and I can hear the turbo again. It does not pull very strongly, certainly not as strongly as during the "spike" but its not limp mode. There are flat spots throughout the rev range. I assume the spike is down to the VNT doing its job?
When travelling in any gear there seems to be inconsistency to the boost pattern. Sometimes there is a lot of torque and other times there is not (still not as bad as limp mode). I have tested this on the same stretch of road to discount gradient etc.
The flat spots I described are similar to but not as violent as when limp mode kicks in. Limp mode is like hitting a wall and is scary if it happens when overtaking! This is still enough to put me off overtaking.
Any ideas as to what is going on? Is the torque (boost) curve supposed to feel like this? I've gone from a Golf VR6 which pulls like a train to the Ibiza. I wasn't expecting similar performance by any means but I did expect a little more than I'm getting.
Apologies for the essay!
Hi All
Over the past couple of months my Ibiza (110bhp) had been going into limp mode more and more frequently. After searching through the forums I performed the following;
- Cleaned the MAF
- Cleaned the EGR
- Cleaned the inlet manifold
I was still getting limp mode so plugged her into VAG-Com and got a boost deviation - intermittent error. After some research I tried the VNT cycle procedure using the diagnostics and discovered the VNT actuator arm was stuck. After two days of work my turbo is now back on the car and spotless, and the VNT test shows the arm moving as normal. Also, from driving around with the diagnostics plugged in I can see that the boost parameters are correct. As are the MAF ones.
There are now no error codes on VAG-Com.
BUT
The car still doesn't feel right. There seems to be an initial spike in boost (Particularly in 2nd gear) at about 2250rpm. This spike then vanishes at around 2500rpm and I seem to loose boost (not completely) until around 3000rpm. Then the car pulls and I can hear the turbo again. It does not pull very strongly, certainly not as strongly as during the "spike" but its not limp mode. There are flat spots throughout the rev range. I assume the spike is down to the VNT doing its job?
When travelling in any gear there seems to be inconsistency to the boost pattern. Sometimes there is a lot of torque and other times there is not (still not as bad as limp mode). I have tested this on the same stretch of road to discount gradient etc.
The flat spots I described are similar to but not as violent as when limp mode kicks in. Limp mode is like hitting a wall and is scary if it happens when overtaking! This is still enough to put me off overtaking.
Any ideas as to what is going on? Is the torque (boost) curve supposed to feel like this? I've gone from a Golf VR6 which pulls like a train to the Ibiza. I wasn't expecting similar performance by any means but I did expect a little more than I'm getting.
Apologies for the essay!
