Limp mode w/o code. Please Help

[thechromecoyote]

I finally get the silicone couplers to pair my new forge wintake with the AWE DV relocation kid I have and bam Im plagued with issues from the get.

One of the MAF sensor screw snaps in the housing, but the other one holds it tight so I just let it go. Car drives fine for a few days. All of a sudden today I keep falling into limp mode.

I know its limp mode bc when I restart the car and give the ECU 45 seconds before starting it up again, I can boost back up to 22 PSI no problem for a few minutes then its back down to 5 psi :frown:

So I do the usual.

Pull dipstick when car is running to check PCV system. Check, idle goes wild with dipstick out. :thumbsup:

DV is Rev D and freshly installed (less than 3 months) but just to be cautious I detached, retached, and tightened all the hoses leading from the TBP to the DV Relocation. :thumbsup:

Now the weird one.... I pull the MAF cable and usually this causes a rough idle but otherwise the boost in unaffected. Same thing as before, car will boost for 2-3 test runs and then drop into limp mode at 5 psi.

So is it my N75? what can I do to test whether thats functioning or not?

All of this with no CEL (well except the expected one from the MAF being disconnected)

Thoughts?

MODS:
APR Stage 2+
Billyboat 3" Catted DP
APR FSI Fuel Pump
AWE DV Relocation kit with stock wiring harness, and Rev D DV
EJ Noise Pipe
Forge Wintake Intake

 

[thechromecoyote]

Bump.

 

[Kishon]

Dude, i sort of have the same problem.... car boosts fine when ever it wants to. Now it doesn't seem to hold boost at all. Tried what you've tried as well but still no joy. And its gone heavy on gas. Mine goes to 1 bar but dies straight after. On the highway yesterday i wasn't getting any boost after 3k rpm. Anyone have any ideas? Runner control maybe?

 

[thechromecoyote]

Usually the flapper motor issues throw a CEL. That's really what's annoying me is that without vagcom I'm working half blind here. Until a code gets thrown its just a mystery... I don't even have any pending faults either.

When you turn your car on next time. Close the door with the key in the ignition for 45 seconds without turning the car on to reset driving habits. If you get boost for a run or two it's limp mode too.

 

[Kishon]

Damn.... hate them limp modes....But what i noticed on mine that when i get to 3-4K rpm, theres a whistling noise....more like a howl coming from the engine bay. I have Vagcom but there aren't any codes. I did once get "runner control deviation" But i think it was a once of error cause i've never seen it again.

 

[thechromecoyote]

Did you run boost logs to see requested vs actual ?

You're lucky, if I had vagcom I'd be all over this posting logs, etc.

 

[Kishon]

Did you run boost logs to see requested vs actual ?

You're lucky, if I had vagcom I'd be all over this posting logs, etc.

No logs as yet, i just could not find the time. However i have taken leave from work tommorow and Friday and I'm hoping i can get some info as to what might be the problem. Why don't you but the VagCom stuff. My cable is not even the Ross-Tech cable. It just has a VAG908 label on it which i picked up for next to nothing and then downloaded the software of their website. Will post some logs once i have them.

 

[PRND[S]]

You're lucky, if I had vagcom I'd be all over this posting logs, etc.

So what are you using to check for codes? I'm sure there is a DTC stored in the ECU since it is putting the car into limp mode.

 

[thechromecoyote]

I'm using a little eBay OBD2 reader and the torque app. It's not good for much else other than clearing and reading codes.

vag com would give me access to logs and hidden faults. I could also do a TB reset or an ecu reset to clear out any bad driving data.

Update: so I triple checked the DV it's definitely good. Tightened everything up and was able to regain boost all day yesterday without issue. Today for half my ride to work its the same 5 psi thing ... Then full boost again.

I pulled the dipstick again while the car was running and instead of a crazy shaking idle, I got a sucking sound from the PCV area. So I'm thinking it's a PCV on its way out, just not fully failed. Which is bs bc this thing is only 3 months old.

Going to try a block off plate tonight then head to my tuners again tomorrow so we can run logs

 

[Crispy21]

no hpfp?

 

[thechromecoyote]

no hpfp?

It's listed up there I said apr fuel pump instead of hpfp is all

 

[Crispy21]

Your right, i missed that. Yea try to fix the pcv and see what happens

 

[thechromecoyote]

Update. Replaced the PCV with block off. Ran nice and hard for a few runs but it's back to 5 psi intermittently


Grrrrrr what on earth could be leaking !?

 

[The Fed]

For future reference, if it's running rough, and unplugging the MAF makes it run smooth, it's the MAF.

 

[The Fed]

When you turn your car on next time. Close the door with the key in the ignition for 45 seconds without turning the car on to reset driving habits.

Where did you read that?