Overboosting after timing belt change??

[Dirtrider0587]

I have a 07 a4 2.0t. I just did the ecs tuning timing belt kit with an underdrive pulley. I also replaced the cam follower, pcv, thermostat, plugs, and cleaned out the intercooler piping. Now im getting a p0234 overboost code. Goes into limp mode when creating boost otherwise slow throttle not creating boost it is fine. I put in a new map sensor and that didnt fix it. Checked voltage to it and it gets 4.9v. Right where i should be. Put the old pcv back in still same thing. Check for boost leaks between all the intercooler piping and none there. It was running perfectly fine before and now its not. I am at a lost. Please help. Any input??

[FraggyA4]

Go back and check that your teeth line up, you might of advanced your timing by one tooth on accident.

[drumnjuny]

yup

[Dirtrider0587]

I marked the belt and installed it the same way i took it off. Correct me if im wrong but wouldnt it cause a timing code or not run right not under boost? I thought that to but thats definitely the last thing i want to take back apart considering its not a very fun job.

[FraggyA4]

When I did mine I retarded it by one toothe it never through a code and under boosted.

You can fix it without removing the front end. At least I was able too. The key is to start with the dampener and get it line up with the mark on the timing belt cover then work your way back from there. Next going to the crankshaft pully than the cam shaft pully. which is probably what you advanced. Try to use the factory markings.

[Dirtrider0587]

alright thanks. i guess i will take it apart again and check. i really dont see any other options at this point anyway.

[Charles.waite]

Timing wouldn't cause overboost. My guess is you forgot to hook something up right (n75) or pinched a vacuum line.

[Dirtrider0587]

Yeah it wasnt timing. I double checked both my timing marks and they line up perfectly. I just double checked all my wiring connections and they are good and plugged in. The only hoses i pulled off were for the intercooler piping and i just refit them again and tightened the clamps and still nothing.

[mec]

wastegate is stuck closed?

[Charles.waite]

Think about what the code says: OVER boost. A leak in the piping wouldn't cause that, it would cause the exact opposite.

Now My best guess is part of the boost control stopped working. Could be the divertor valve. But I'm still leaning towards the N75.

http://wiki.ross-tech.com/wiki/index...8/P0234/000564

Ross-tech agrees.

It could be the wastegate though, but thats not the first route I'd explore.

[mec]

did you reconnect the map sensor on the driver's side intercooler?

[Dirtrider0587]

Alright well i had checked the wiring to the n75 valve before and visually inspected the hoses to it but i went back to recheck them again like you said and the nipple on the valve was cracked i grabed the hose and it came right off. I appreciate the help wouldnt have rechecked it if you didnt say something. That is most definitly the culprit now i have to order another one. Maybe the upgraded race version?
Thank you

[Charles.waite]

Alright well i had checked the wiring to the n75 valve before and visually inspected the hoses to it but i went back to recheck them again like you said and the nipple on the valve was cracked i grabed the hose and it came right off. I appreciate the help wouldnt have rechecked it if you didnt say something. That is most definitly the culprit now i have to order another one. Maybe the upgraded race version?
Thank you

Oh god no. Aside from the "race" versions causing tons of problems, they're for the 1.8t, and won't even come close to working for a 2.0t.

Here: http://www.ecstuning.com/Audi-B7_A4-...lve/ES2574871/

Get that one, its OEM. Glad you figured it out though. Those damn plastic nipples are so easy to break if you aren't careful.

[Dirtrider0587]

Yeah never mind i looked them up and there not for my car. My last car was the 1.8t gti. My bad no race version. I just ordered the oem one.

[Dirtrider0587]

Guess what? Got that fixed and now im under boosting. Doesnt have much power and get code p0299. Do you think i harmed my wastegate or dv? Thats my guess.

[mec]

Pull the dv, check for tears

[moh1977]

Yea p0299 is usually an issue with the dv. I had that problem a month ago, took out the dv and sure enough it had a tear. Replaced it and all is good.

[FraggyA4]

You probably blew out the DV when you were over boosting. Sorry for the misguidance but I guess I learned something here.

[Dirtrider0587]

Not a big deal. I was taking any input i could. I had searched high and low to find that stupid issue with the n75. Yeah when i was trying different things i would go down my street to see if it was fixed and the dv sounded really loud. Im sure it blew it out. I will check it tom. Right now im up at a car show. I just hope its not the wastegate i wasnt ready to spend on a new turbo yet.

[Dirtrider0587]

Dv has no tears