So today I got on the freeway and when I went to accelerate up to speed my car starts to jerk around really hard. Like the engine just felt like it was cutting out. I looked at my dash to see if I was getting a missfire (thats what it felt like) but there was no CEL on at all. It never flashed once and never came on. I let off the throttle and the car ran fine again. So I started to accelerate again and it did it again. I was getting really mad now. I looked at all my gauges and they seemed normal. Then i decided to watch my boost gauge when I accelerated to see what it did. This is where it gets interesting... First off I am not chipped at all so I SHOULD (that being the key word there) be boosting about 8-9 PSI max. Well when I hit the gas it went up to 16 PSI and thats when it starts jerking again. It's a REALLY bad jerking to... It just started doing that randomly out of the blue. Any ideas???? I am really starting to regret getting this audi.

It's a 99.5 A4 1.8T with about 91K miles. The only upgrade engine wise is a Forge 007 DV.

Here is a video of my boost gauge when it starts jerking (It was taken with my cell phone so it's kind of sucky):
http://www.youtube.com/watch?v=1rhStKcsjLo

Josh

Edit*** Oh and there are no codes.

 

Ihad that same throttle cut in and out when i installed an N75 J valve with a4.7 diode. just i was spiking at 25 psi when it was happeneing. maybe your n75 went to poop?

 

Thats what i was thinking to. Can anyone else confirm that?

Josh

 

Ok, so another question, If I bypass the N75 valve I know I still need it plugged in electronically but will it still cause the throttle cut out even though then Vac/Boost lines are unplugged?

I REALLY need an answer to this quick. I have searched and couldn't find anything for it. PLEASE let me know ASAP! I can't really drive my car right now.

Josh

 

you can drive it just dont hit boost.
Idon't think its the greatest ideato drive your carwithout having your vac/boost lines plugged intoan n75/mbc.
I would just leavethe N75 pluggedin acting crazy and just drive like a pu$$y for a bit until you can get a new one.

 

is your forge adjustable ?

r u using mbc ?

I have my n75 just plugged electronically, that's all.

 

if you leave them unplugged then prob. turbo could not build any boost because of wg will be wide open all the time then when you wot car will be run rich big time.

 

LOL, ok I miss typed that. What I am wondering is in the "How to hook up an MBC" thread it shows a MBC that is hooked up with out using a N75 valve. Do I need to have the N75 valved plugged in electronicly but w/out the Vacuum lines? If I AM able to, do I still need to buy a new one or will the messed up one be ok since it isn't controlling anything?

And no I don't have a MBC plugged in right now.

Josh

 

Anyone have any idea if that will work or not??? Please??? I really want to get this fixed.

Josh

 

you have to keep the N75 plugged electronically thats all. do not hook any hoses. use tape or something to block all 3 hoses on N75.

if you do not keep n75 plugged, then you will get code.