Timing Pulled, Fuel Cut or WTF? 2G

[Ryan95tsiAWD]

So I was driving along at 45mph or so and hit a recessed railroad track. The car didn't cut off or do anything crazy but the next time I went WOT the car felt like it was pulling timing like crazy after about 10lbs. First off, I have dmslink, and all supporting mods (fmic, 650s, 255fp/rewire, etc.) with an e16g. I have not done a capture to see exactly what it is as my laptop is dead right now. I have my CEL set for knock at a very low count and have not seen it come on yet. I did a boost leak test and did find a couple of lines that were off. One that went to the fuel rail and the other connects to some valve below the TB. Sorry, I really havnt worked on DMSs in a few years so i forget what it is called. Anyway, after I put those back on, 20lbs+ air would stay in for a long time. I was testing from before the turbo. I would have thought it would be a boost leak as that is what it feels like. Next step, gapped and install new bpr6es plugs but it still does it. I have pushed it a little even after the car goes to crap and it still builds boost. At this point i am out of ideas. Anyone know what i could have "bumped" that would cause this?? Thanks.


EDIT: If this makes any sense, It feels like the car is hitting a rev limiter as soon as there is enough load on the motor to cause the issue. It Doesn't matter what RPM i am at. I can take the car up to redline at half throttle and minimal boost (5lbs or less), although I think that would still be in open loop mode(please correct me if I am wrong).

 

[Ryan95tsiAWD]

OK, got a run on link. I cannot do a full pull as the car's power dies out as soon as i hit 10lbs. I did push a few RPMs higher but am scared to push it to redline.

 

[Ryan95tsiAWD]

Does anyone have any suggestions as to what else I could try?? I have another DSM that I can pull parts from to test anything.
Is there any other information I could provide to help figure this out?

 

[kahl23]

I'm having issues looking at that log, it won't download for some reason. The vacuum line to the fuel rail was probably going to the stock fuel pressure regulator, and the valve below the throttle body was probably the EGR valve. The only idea I have now is that maybe somehow your CAS got messed up when you hit those tracks. I would say get a timing light, ground timing using DSMLink, and make sure your base timing is set correctly. Also, see if you can post the log again or something.

 

[Ryan95tsiAWD]

I did another boost leak test, this time I turned the compressor up to about 40lbs. I was able to make one of the fuel injectors leak air. Pulled them and the seals have gone bad or close to it with the worst one being the one that leaked. Would motor compression be the reason why it would only show up under load but not during a normal boost leak test? How much pressure do you guys normally push into the system when testing for leaks??

Now I am waiting for seals to come in, hopefully this will fix it...

 

[kahl23]

That could very well be your issue. My BLT doesn't have a gauge on it, and running into the driver's seat to check the boost gauge is a pain, but I usually test to over 20lbs I actually had the same problem as you, a leaking injector seal caused the car to just fall flat on it's face whenever I reached full boost. Try replacing that and then post back.

 

[Ryan95tsiAWD]

Seals replaced but it still does it. I still think it feels like a "strange" boost leak. I am going to test the system again while pushing and pulling on every damn clamp/pipe. If it was the CAS wouldnt the car hesitate like crazy when you gave it gas? I am able to take the car to redline smoothly as long as I don't try to push it WOT or more than about 5lbs of boost. I will grab another log this afternoon and post. If it helps, I am running DSMlink v2.5.2.21 .

 

[kahl23]

Still think it's a boost leak. Get some water mixed with dish soap and slather it over everything, every joint, every connection. Look for bubbles and use a mirror to check places like the underside of the throttle body.

 

[->PrOjEcTGS<-]

What BOV are you running? Stock 2g? 1G?

If that's leaking it will rob you of power. Whether it's recirculated or not.

Also, check your plug wires. Possibly pull them off your parts car and see if that helps.

Also, your knock sensor could be bad you could try swapping that from your pars car.

 

[Ryan95tsiAWD]

I have 2 Type-S BOVs (real ones) have checked both and swapped them just to be sure. I am re-circing the air.

I may just go buy some new NGK wires, i dont think my other set is in any better shape. Will check resistance on them to see.

I was wondering what happened when a knock sensor went bad, although Link isn't showing knock and the timing isn't dropping any worse that any other runs I have logged.

Also, I swapped the MAS since I had it off to BLT anyway.

The only difference I noticed between a previous "good" log and the current one is how long it took for the A/F ratio to drop down to the appropriate level after I went WOT. As soon as you go WOT, shouldn't your A/F ratio drop and stay at roughly the same level (assuming a good tune) throughout the pull?

The old log shows as soon as I go WOT the A/F ratio drops to 10:1 and stays for the entire pull (or close, afterall the is an estimate value in Link). The new log shows my A/F ratio taking a little more than 1k RPMs of WOT to drop down to 10:1 and even looks to be dipping lower right as the problem occurs. /confused

Will log again on the way home tonight.

EDIT: Added Log.

 

[Ryan95tsiAWD]

Swapped in my old NGK plug wires and the car works fine again...go figure.

cudos to ProjectGS

Thanks everyone!

 

[viperlp01]

damn simple shit ...

 

[->PrOjEcTGS<-]

Sweet...

 

[kahl23]

Haha that's great, glad to hear that you got everything worked out.

 

[Ryan95tsiAWD]

Did I mention I hate my DSMs?

 

[kahl23]

Don't we all sometimes?