bosch maf not allowing full boost?

[gti_shaun]

hi all, i recently had a MAF fault on my AGU, as the car was pulling back and revs dropping right down on idle,(ALSO HAD MAF SIGNAL LOW FAULT CODE) after logging the maf on VAG-COM the reading was doubling on idle so causing incorrect fuel etc, anyway i bought a bosch maf as i thought they make them for vw anyway so should be ok, fitted it, it sorted idle issue and the pulling back and runs sweet, but when i have started the open up the throttle and give it some on the motorway, it is not going to 21psi peak boost like it used to, it only goes to 18psi and drops and holds about 14psi , its had made the car feel quite a bit slower and took the seat pinning feeling away, and is no where near as giddy spinning up the wheels when i purposely floor the throttle when i have been testing it.

sorry about the essay

i could do with a very kind AGU owner willing for me to borrow their MAF for 5mins to see if it is that or i have got a boost leak or something instead, but it would seem to have only gone like this since new bosch maf was fitted.

[master_oogwai]

hi all, i recently had a MAF fault on my AGU, as the car was pulling back and revs dropping right down on idle,(ALSO HAD MAF SIGNAL LOW FAULT CODE) after logging the maf on VAG-COM the reading was doubling on idle so causing incorrect fuel etc, anyway i bought a bosch maf as i thought they make them for vw anyway so should be ok, fitted it, it sorted idle issue and the pulling back and runs sweet, but when i have started the open up the throttle and give it some on the motorway, it is not going to 21psi peak boost like it used to, it only goes to 18psi and drops and holds about 14psi , its had made the car feel quite a bit slower and took the seat pinning feeling away, and is no where near as giddy spinning up the wheels when i purposely floor the throttle when i have been testing it.

sorry about the essay

i could do with a very kind AGU owner willing for me to borrow their MAF for 5mins to see if it is that or i have got a boost leak or something instead, but it would seem to have only gone like this since new bosch maf was fitted.

I am experiencing the same problem with my AGU plus the car is still holding back ever since I swapped out the maf 2 weeks ago. Checked on vagcom, but no faults came up. The next thing I am going to try is to swap out the n75 valve as suggested by others and see this makes any difference.

[topher]

i have one you can borrow for 5 mins. If you're worried about leaks i can stick your car on the smoke tester for some beer tokens

[DarkGti]

ive got exactly the same problem, ive had new turbo, new maf, new n75 valve and still im only boosting at 15-18psi think ive got a boost leak somewhere

[gti_shaun]

i spoke to nick at R-tech and if i dont get anywhere he said he would stick it on the leak tester and have a look over it. thanks anyway topher, TBO i dont think i have a boost leak, its to much of a coincidence that it happen stright after the new maf,

if you get anywhere master_oogwai please let me know and i will do same, what MAF did you fit gen or bosch?

Ive just had a good visual inspection of all pipes etc, with no obvious leaks, ive also used a mitivac to test the actuator for leaks(OK)

are you down leicestershire tho topher, i could do with someone a little more local, i just want to hopefully prove the new maf is at fault get my pennies back and go VW for one

 i hate it when threads like this get left with no answer(FIX) so i will keep you all posted.

[D4VEY01]

Also mines the same, since i added a forge TIP the car went well at first then a week later the power kind of dropped off and its not like it used to be.When i fitted the TIP i had to trim a small piece off the hose to make it fit at the turbo,this surely cant make a difference.Or is it a change in the weather who no`s..

[master_oogwai]

Will do mate. I got my new Bosch one from my local vw branch.

[richw911]

i spoke to nick at R-tech and if i dont get anywhere he said he would stick it on the leak tester and have a look over it. thanks anyway topher, TBO i dont think i have a boost leak, its to much of a coincidence that it happen stright after the new maf,

if you get anywhere master_oogwai please let me know and i will do same, what MAF did you fit gen or bosch?

Ive just had a good visual inspection of all pipes etc, with no obvious leaks, ive also used a mitivac to test the actuator for leaks(OK)

are you down leicestershire tho topher, i could do with someone a little more local, i just want to hopefully prove the new maf is at fault get my pennies back and go VW for one

 i hate it when threads like this get left with no answer(FIX) so i will keep you all posted.

Nick will use the same smoke tester.......

Topher = R - tech 

[northeast_gti-t]

ive got exactly the same problem, ive had new turbo, new maf, new n75 valve and still im only boosting at 15-18psi think ive got a boost leak somewhere

yours is an AUM isn't it Ry? maybe worth binning the pcv pipework mine was split on one of those pipes 

[Wazzzer]

i spoke to nick at R-tech and if i dont get anywhere he said he would stick it on the leak tester and have a look over it. thanks anyway topher, TBO i dont think i have a boost leak, its to much of a coincidence that it happen stright after the new maf,

if you get anywhere master_oogwai please let me know and i will do same, what MAF did you fit gen or bosch?

Ive just had a good visual inspection of all pipes etc, with no obvious leaks, ive also used a mitivac to test the actuator for leaks(OK)

are you down leicestershire tho topher, i could do with someone a little more local, i just want to hopefully prove the new maf is at fault get my pennies back and go VW for one

 i hate it when threads like this get left with no answer(FIX) so i will keep you all posted.

Nick will use the same smoke tester.......

Topher = R - tech 

dammit you got there before me