"Boost Controller Solenoid N75"

[RobM]

Yes, definitely. You might find the performance is a little lacking (equally you might find it's the same) but you should notice the power is now smooth and not lumpy as you described before.

If this is the case and the car is smooth with the MAF unplugged, you have more than likely found your problem.

 

[Number86]

If the MAF s necessary, how can you drive the car around without the MAF?

I'm occasionally experiencing a problem which sounds like it could be attributed to either the MAF or the N75, but i'm a spaz when it comes to fiddling with engines, and am a bit scared to start pulling things apart!

 

[Feel]

If you disconnect the MAF, the car assumes it's failed and drops back to a "fall back" situation where it calculates the MAF value from the MAP and the IAT.

Not the most accurate (especially if your MAP is normally maxxed out), but can give a better reading than a duff MAF, hence the car running better.

 

[Number86]

gotcha.

Thanks brains!

 

[sssstew]

taken from the VAG TDI Tech article :-

Substitute function
If the air-mass flow meter fails, the control unit defaults a fixed air mass value.
This fixed value is calculated such that a reduction in engine performance can only occur in the part-throttle range.

 

[m.r.davies]

Thanks Guys

This might be helpful

 

[Johnny Hotrod]

taken from the VAG TDI Tech article :-

Substitute function
If the air-mass flow meter fails, the control unit defaults a fixed air mass value.
This fixed value is calculated such that a reduction in engine performance can only occur in the part-throttle range.

Thats interesting as my car is lumpy on part throttle but i've changed MAF & its still the same

 

[traumapat]

Thats interesting as my car is lumpy on part throttle but i've changed MAF & its still the same

its not unknown to get a "new" dodgy maf. have you checked for faults with vagcom?

 

[Johnny Hotrod]

its not unknown to get a "new" dodgy maf. have you checked for faults with vagcom?

Thanks for the advice. Its been on a diagnostic but no faults were shown. However i disconnected the MAF earlier & drove round the block & it seems fine. Maybe it could be a dodgy one. I'll leave it disconnected for a couple of days & see how it goes...

 

[traumapat]

Thanks for the advice. Its been on a diagnostic but no faults were shown. However i disconnected the MAF earlier & drove round the block & it seems fine. Maybe it could be a dodgy one. I'll leave it disconnected for a couple of days & see how it goes...

careful mate. running for too long maf unplugged could mess up the cat.

anyone local with a known working maf you could try swaping with? vagcom could read the mafs output whilst you drive.. see if its working right.

get friendly with a local on here with vag com.

 

[Johnny Hotrod]

careful mate. running for too long maf unplugged could mess up the cat.

anyone local with a known working maf you could try swaping with? vagcom could read the mafs output whilst you drive.. see if its working right.

get friendly with a local on here with vag com.

Thanks i'm just leaving it for a few miles to see if it really is running fine unplugged. I'm new to the Leon & dont know anyone round here with one or with Vagcom. Bell Autos is not too far from me though so may give them a call & see if they can help.

 

[traumapat]

Thanks i'm just leaving it for a few miles to see if it really is running fine unplugged. I'm new to the Leon & dont know anyone round here with one or with Vagcom. Bell Autos is not too far from me though so may give them a call & see if they can help.

have a really good search on here for each symptom. (leon section) you`ll get loads of info on your car.
some of us get a power drop at around 3k revs. car runs fine when accelarating but if its only pootling as such theres a sudden loss.

if its that dont go crazy replacing bits yet as the ones on here suffering have tried everything.

have a read mate

 

[Johnny Hotrod]

have a really good search on here for each symptom. (leon section) you`ll get loads of info on your car.
some of us get a power drop at around 3k revs. car runs fine when accelarating but if its only pootling as such theres a sudden loss.

if its that dont go crazy replacing bits yet as the ones on here suffering have tried everything.

have a read mate

Will do. I dont get a power drop as such it can just be a bit lumpy on part throttle when accelerating slowly between 1500-3000 rpm. Once turbo cuts in all is fine. I'll get searching!

 

[Big_daddy]

Problem solved for me! Power back!
Replaced the N75 from seat, cleaned and checked forge DV, ecu reset and TB reset!

 

[RobM]

Nice one, problem solved