[orionredwing]

Hi, I did a couple of searches related to HPFP, wastegate and loss of boost pressure issues, but nothing seemed to match up 100%. I can sure use everyone’s expert help!

Problem: Loss of acceleration, eventually resulting in almost no acceleration, but no error codes thrown by car.

I was accelerating hard in 2nd gear when all of a sudden, I lost all power and could not accelerate anymore. In 6th gear, I would be stuck at 2k RPMs around 60-65mph and it would take 5-10 secs to go up to 70mph. Likewise no power accelerating from stoplight, and car would vibrate while accelerating.

- Problem triggered initially by hard acceleration.
- If I downshift, my car would rattle while accelerating.
- While idling at a stoplight, my car would vibrate slightly.
- After I restart the car, I would regain power, but I would pull noticeably less than before. But more power than if a check engine (SES?) error code is thrown (I’m not in limp mode). Restarting car eliminates rattling and vibration during acceleration.
- NO ERROR CODES thrown at all.
- No rattling sound indicating a wastegate problem (never had that noise).
- I was able to repeat the problem once more. I accelerated hard in 2nd gear. This time, I heard a mechanical click/shifting sound right before I lost all power again. Restarting the car was able to let me accelerate again at reduced power.

What’s been done recently:

- 3-4 weeks ago, I took my car in for my 2nd HPFP replacement. In previous failures, I would go to limp mode, but can still accelerate to 85mph w/ no boost. Prior HPFP failures resulted in the check engine (SES?) error code thrown, going into limp mode.

- While replacing the HPFP, dealer replaced my exhaust camshaft seal.

- Standard maintenance done. Spark plug replacement.

- My car is still pre 29.2. The invoice did not indicate a progman update, and I do not feel the lag that everyone talks about post 29.2.

- The only mod done recently was a Wavetrac LSD installation 2 weeks ago. Problem occurred after installation. However, mechanic says this may be a coincidence because the failure mode doesn’t seem related to an LSD. I also confirmed that my LSD is still working by taking corners harder w/o the traction control light tripping.

Thanks for your help!

[cn555ic]

what I find is weird is the fact that you have replaced the fuel pump twice and you still think that your on the pre 29.xx program....I would find that impossible because from all the threads that I have read, the program was updated to the newest version...With that I would just bring it back to the dealer and let them diagnose the problem that your having...It would seem like they messed up something, so rather than break your head trying to troubleshoot, take it back...good luck

[scalbert]

What other modifications are on the vehicle?

If just the LSD, and the problems occured just after the installation and while I would never point my finger at such an item, the coincidence is striking. This vehicle is quick to to throw a code. Are you sure there is not a shadow code?

[orionredwing]

Yes, I will schedule a service appointment soon, but loaner cars are always 2-3 weeks wait here.

As a car enthusiast and an engineer iRL, it's in my nature to learn as much as possible, rather than taking it into a dealer blindly. Plus, if I have a better understanding of the problem, it may help the dealer diagnose the problem a bit better, or prevent them from just returning the car back to me because no error codes were thrown.

I still think I'm on pre-29.2 because my:
RTTS update is super slow (annoying when I drive from Bay Area down to LA and hit rush hour)
MP3 song scrolling is super slow
DVD Nav menu is still brown
No lag (although I heard latest update fixes that?)

Can your progman be updated w/o these features being enabled? That's why I still think I'm pre-29.2.

Originally Posted by cn555ic

what I find is weird is the fact that you have replaced the fuel pump twice and you still think that your on the pre 29.xx program....I would find that impossible because from all the threads that I have read, the program was updated to the newest version...With that I would just bring it back to the dealer and let them diagnose the problem that your having...It would seem like they messed up something, so rather than break your head trying to troubleshoot, take it back...good luck

[orionredwing]

The only other mods I have is a Procede Rev 1 (map from sometime in '08), and a drop-in K&N filter. I also have a Steptronic.

Can you think of anything in an LSD install that may cause this problem?

I only have an OBDII reader (don't have the BavTech tool), so I don't know if any shadow codes were thrown. Just no std OBDII codes or check engine lights visibly thrown.

Originally Posted by scalbert

What other modifications are on the vehicle?

If just the LSD, and the problems occured just after the installation and while I would never point my finger at such an item, the coincidence is striking. This vehicle is quick to to throw a code. Are you sure there is not a shadow code?

[scalbert]

Originally Posted by orionredwing

The only other mods I have is a Procede Rev 1 (map from sometime in '08), and a drop-in K&N filter. I also have a Steptronic.

Can you think of anything in an LSD install that may cause this problem?

I only have an OBDII reader (don't have the BavTech tool), so I don't know if any shadow codes were thrown. Just no std OBDII codes or check engine lights visibly thrown.

Just as a precaution, I would pull the PROcede and see if the problem occurs. I am not familiar with the Wavetrac LSD but a clutch based unit could slip. But not in this manner from what I have experienced. But it would be best to eliminate items to isolate the problem.

[orionredwing]

I updated to the 7-29 map today at 75% tq, and tried the data logging features. After 5 pulls, I was able to duplicate the problem again. Luckily, I captured the event mid-run on the data logger so can share.

The event happened a little after the 12s mark where the slight dip in 100% throttle occurred. After I went back to 90% throttle, I was only making ~6.1psi of boost at the 14s mark.

Prior to the 12s mark, it shows my peak boost a lil over 15 psi. Just right before the throttle blurp, there were 2 data points or ~0.04s of16.0psi. It then drops down to ~10psi of boost at the throttle blurp min point (~70% throttle).

After that my throttle blips back up to 90% but I'm only making 6-7psi boost. I may have shifted into 3rd right before the 15s mark. I forget.

Is there an ECU trigger that happens as soon as 16.0psi is reached, or was that just a coincidence? My Procede overboost protection is at the default (1 sec?), so I don't believe it's the Procede tripping.

After this occurrence, I get the rough idles at the stoplight, which goes away as soon as I restart the car. After I restart the car, it pulls noticeably less powerful. I have a data log of that, but haven't analyzed the before/after yet.

Do you guys have any idea what may be the problem? (I didn't pull the Procede out yet because I wanted to take advantage of the data logging capabilities).

[OpenFlash]

Originally Posted by orionredwing

I updated to the 7-29 map today at 75% tq, and tried the data logging features. After 5 pulls, I was able to duplicate the problem again. Luckily, I captured the event mid-run on the data logger so can share.

The event happened a little after the 12s mark where the slight dip in 100% throttle occurred. After I went back to 90% throttle, I was only making ~6.1psi of boost at the 14s mark.

Prior to the 12s mark, it shows my peak boost a lil over 15 psi. Just right before the throttle blurp, there were 2 data points or ~0.04s of16.0psi. It then drops down to ~10psi of boost at the throttle blurp min point (~70% throttle).

After that my throttle blips back up to 90% but I'm only making 6-7psi boost.

Is there an ECU trigger that happens as soon as 16.0psi is reached, or was that just a coincidence? My Procede overboost protection is at the default (1 sec?), so I don't believe it's the Procede tripping.

After this occurrence, I get the rough idles at the stoplight, which goes away as soon as I restart the car. After I restart the car, it pulls noticeably less powerful. I have a data log of that, but haven't analyzed the before/after yet.

Do you guys have any idea what may be the problem? (I didn't pull the Procede out yet because I wanted to take advantage of the data logging capabilities).

Rough idle at stop that goes away upon restart sounds like misfire due to old spark plugs. No code at all??

[orionredwing]

No code tripped at all. They did replace my spark plugs (std maint) when I went into service for the HPFP & exhaust camshaft seal replacement a few weeks ago.

Originally Posted by shiv@vishnu

Rough idle at stop that goes away upon restart sounds like misfire due to old spark plugs. No code at all??

[OpenFlash]

Originally Posted by orionredwing

No code tripped at all. They did replace my spark plugs (std maint) when I went into service for the HPFP & exhaust camshaft seal replacement a few weeks ago.

Wait a sec. Looks like you are going into valet mode. I can tell by the Fuel correction $ taper back to zero (which brings boost back down to stock level). Next time, log "current map selection" and see if your map goes from 1 (map1) to 0 (valet) in the middle of the run. If it does, you can look at a debug parameter and see what is triggering it (over DC/boost leak, leanrun or overboost).

Shiv

[orionredwing]

Thanks Shiv! I think that may be it!!

I just took a look again and the default Overboost Limit is 16psi with the Overboost Delay at 10ms.

So my 2 data points or 0.04s at 16.0psi did trip Valet!

I was confused because I set the Valet option to OFF but I understand now that's different from the Procede taking you to valet mode as a safety feature.

Woo hoo!! I'm glad my car works! Man, I was so bummed because I thought my car's reliability sucked and that I couldn't hit the track/play with this car again for fear of limp, breakdowns, or what not.

Originally Posted by shiv@vishnu

Wait a sec. Looks like you are going into valet mode. I can tell by the Fuel correction $ taper back to zero (which brings boost back down to stock level). Next time, log "current map selection" and see if your map goes from 1 (map1) to 0 (valet) in the middle of the run. If it does, you can look at a debug parameter and see what is triggering it (over DC/boost leak, leanrun or overboost).

Shiv

[orionredwing]

Oh boy, it's not valet mode. I logged 'current map selection' and it never switches to 0.

I tried 10% torque settings and it still trips. I finally got the half engine limp mode to trigger, which goes away on restart (doesn't require key fob reset).

Because this happens only in WOT from 2nd to 3rd gear, I have a nasty suspicion it's the fuel pump....again... <sigh, I'm on my 3rd>.

At some point, can it be something other than the pump? Like are there hoses, lines or anything that's in line with the HPFP, or do those get changed automatically upon a HPFP replacement?

I will pull the Procede later. It's 100deg F outside atm, so maybe temp is a factor.

But for now, it doesn't affect my daily driving, but I just can't step on the throttle aggressively

[orionredwing]

Updated data:

1) Pulled Procede and used bypass plugs (kept Procede harness in). Problem went away.

Note: Per above, 10% UT non-doomsday still caused the problem. Lagfix ON for all test conditions. I did try Lagfix OFF on a non-doomsday map, and it still tripped.

2) Reinstalled Procede and loaded Doomsday 75% UT 100% Ign Corr 7-29 map. PROBLEM GONE.

Analysis:
Maybe my car was re-programmed, but I still have the original features from Dec 06 - brown Nav screen, slow MP3 song scrolling, slow RTTS. I didn't think a program can be updated without me getting the new features? It doesn't actually affect the drivability of the car like it's happening for me?

Question:
Why does 10% UT non-doomsday map fail, whereas 75% UT Doomsday pass?

I don't think I've read in the forums of anyone encountering probs like mine. Specifically, I thought that for post 29.2 cars, you can run the non-doomsday map problem free if you don't mind the hidden tuner codes being triggered?

Thanks for the help.