Volkswagen Passat Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
2,312 Posts
Discussion Starter #1
(98 1.8t giaced, k&n, air box mod) i only notice this at high speeds (70+) when i really get on it on the highway, espacially if someone else is in the car, i get a really wierd pulsating effect in the acceleration, you can feel it and its almost audible, mostly i notice it if i'm in 5th at low rpm (2.5k) and i step on it to the floor. sort of like it's struggling to get to the higher rpm's. anyone else experience this?
 

·
Registered
Joined
·
3,525 Posts
it might be simialar to what i am experiencing, is it sort of like the feeling you get when you let off the gas in a lower gear and the tranny bangs against itself, except you are excellerating? have you replaced your dv? i have not yet.

¤Daniel
 

·
Founder of the STFA
Joined
·
8,668 Posts
Sounds like a possible failing DV. The pulsating is the erratic boost. My $.25 guess.
 

·
Registered
Joined
·
2,312 Posts
Discussion Starter #4
i just replaced my dv a month ago with a TT one. also i have a loud sharp flapping sound when the boost comes in, usually when my car is cold but only in 1st gear or sometimes 2nd gear, once it's up to temp it doesnt do it anymore. :???:
 

·
Registered
Joined
·
1,219 Posts
I notice at all speeds are gears that above 3800RPM my boost seems to go away for the most part and it gets a little figidty could it be my DV???
 

·
Registered
Joined
·
3,525 Posts
yeah, my problem is when its cold, and in first and second. sounds like we may have a similar problem what is this sharp flapping sound. where do you think it is originating? have you done any tune ups to your car lately? my engine is completely stock.

¤Daniel
 

·
Registered
Joined
·
1,219 Posts
No flapping from me but when my engine is cold the i can't go over about 2800RPM's until its warm or else the turbo will surge and kick in and out very roughly.
 

·
Registered
Joined
·
3,525 Posts
hmm maybe i might have somthing similar, maybe this could have something to do with the wastegate?

¤Daniel
 

·
Registered
Joined
·
1,000 Posts
B5veedub said:
I notice at all speeds are gears that above 3800RPM my boost seems to go away for the most part and it gets a little figidty could it be my DV???
Well actually I've been studying up a little bit on turbos and found out that once you get past a certain RPM, you start to lose the efficiency of the turbo boost. There is a certain "sweet spot" in your RPM range that once you hit it, your car will just keep on accelerating like mad. The trick is to stay with in that sweet spot. My car is chipped, so having a boost guage really helps you understand how your turbo works.

As for the fluttering/surging feeling, check your vacuum lines. They tend to break up really easily because they are only made of rubber. If there is no visible damage, then you can always try the dish washing soap and water method.
 

·
Registered
Joined
·
2,312 Posts
Discussion Starter #11
IDriveB5 said:
hmm maybe i might have somthing similar, maybe this could have something to do with the wastegate?

¤Daniel
thats what i'm thinking. my girls b5 has the same milage as mine (75k) and she just had her turbo replaced due to loose wastegate rod. her flapping noise was when she released the accelerator though, mine is when the boost kicks in in 1st and 2nd. i'm going to check it out tonight(the wastegate rod) and i'll post up any findings.
 
1 - 11 of 11 Posts
Top