Only making 4psi, limp mode? v. 99 Audi Avant 1.8t **ISSUE FOUND**

NYSpeed Automotive
1

Now that I have the boost gauge in I see that its only making a consistent 4psi. I did some quick searching on the tex and it soudns like its in some sort of soft limp mode.

I dont have any CELs.

The car has 145k on it, all stock and original.

If its a boost leak, its damn consisntent.

Im thinking its either N75, diverter, or possibly just old turbo related.

I dont currently have vag-com to scan with. I think I can probably borrow someones setup to do so if that might help.

Thoughts??

Thanks,

Dan

2

Post on DITB for someone with a vag-com. There are people on there that will meet up with you. Not to familiar with the 1.8t since i have never owned one.

3

most likely a boost leak, n75 or stock divertor valve… I have an extra Dv you can have… I will be at NYI tommarow if ya want it PM me

4

could it be MAF related? on my 01 Jetta TDI, it was in a limp mode with no CEL and the problem was completely fixed with a $30 used MAF off ebay. check your MAF first and see if it looks burnt inside or anything

5

I bet your wastegate acutator is shot.

6

sounds like a good possibility…

throw a couple Viagra in the gas tank at your next fill up and see if it exits limp mode for a while. note: this is only a temporary fix and if your boost spikes for too long, make sure you consult a doctor.

7

it would make 0 psi if it was the actuator,

its not the actuator

8

I had a boost leak on my 2000 A4 1.8T and it was consistent. I honestly think that I was running the car as a 1.8NA as when I got it back it felt much different. There is a hose off the intake manifold that has a 90 degree bend in it and that is the one that is 99% of the time the culprit. I also do not believe that there was a CEL on from the boost leak, but, this was a LONG time ago and my memory is horrid.

9

Thanks for the input guys. I have yet to look at anything as I just figured out the boost issue on the way to work this morning. Ill probably poke around some tonight, see what I can find.

Hopefully its just a simple boost leak somewhere, but if I must upgrade some parts to fix it thats ok too.

Dan

10

If there is a boost leak - there’s a vac leak somewhere too…

what’s your Hg at?

11

^ Id have to look, I dont recall the exact number at idle now.

12

Unplug your battery for 15 mins, plug it back in… drive.

Does it still do it?

13

No dont do that!!! DO NOT UN HOOK YOUR BATTERY IF YOU DONT HAVE THE RADIO CODE!!! YOU WILL HAVE TO PAY SCHMITTS $90 TO TURN YOUR RADIO BACK ON… ILL REPEAT ONE MORE TIME DO NOT DISCONNECT THE BATTERY!

14

Now check to see if the radio code is in your owners manual if it is, go ahead and un hook the battery

15

^lol … right.

Dan

16

wow…

17

not to mention a throttle body adaptation, great advice :ham:

18

That’s hilarious that you had to pay for a radio code. Helps to make friends at your local VAG dealers.

19

I really need to get my VAG going. Guess that just came up to the top of my list.

20

? OH NOES!

do it, i bet it fixes your problem.