Nevada_TDI
Top Post Dawg
Seriously, I am sure I did not win the W-T-F? award but I am damn close I am sure... I may not get this in perfect chronological order but I will try.
1. Engine starts losing power at higher RPM's: power band keeps getting shorter and shorter, but as long as she starts and gets me to work everyday I will wait until Winter Break to figure it out.
2. Along with power band getting shorter engine starts to hiccup: full power, no power, full power, etc., etc.
3. At this point anything over 1/2 throttle and engine feels like it died.
4. Suggestion is made maybe overboost condition is cutting back fueling: VCDS is only showing 300 millibar of overboost, not enough to cut fueling in software.
5. I replace the fuel filter in case it may be plugged. Not only was it not plugged but there was not not fuel at the lower edge of the the "tee" like there has been in the past.
6. Maybe the check valve thingy in the fuel sender is plugged. I drilled it out and re-installed it. That wasn't the problem either.
7. Strange noises are coming from passenger side of car, RPM dependent, most likely dying pump. I replaced the pump. That didn't fix the problem either.
8. Connected mity-vac to fuel supply headed to tank, minimal fuel, lots of bubbles; in fact enough bubbles for fuel to drain back into supply line
9. Took car for test drive in daylight with VCDS connected now I am showing correct requested boost and 845 millibar actual. This is an almost new 3 bar sensor that is now apparently dead. I removed it and flushed it with brake cleaner and it was still dead.
10. Now what? Re-install 2.5 bar sensor and re-flash original tune.
11. After cleaning and re-installing 2.5 bar sensor the real problem is now obvious: 800 millibar above requested; I guess there was a fuel cutting issue. All this excess boost doesn’t make any sense the car used to run strong and predictably and now this crap.
12. Put the car up on ramps and noticed something that did not make sense: the threads on the actuator shaft were missing, as in the shaft was as short as it could be W-T-F??? Apparently I did not spend as much time checking to see that the lock nut was tight as I did setting the lift at 3” and the stop at 18”.
13. I just guessed and set the thread length above the nut approximately 3/8” and took her for a test drive as frustration was beginning to set in and at the last second I decided to drill out the fuel pickup with the “proper” sized drill bit; the one that the biggest I could fit in there w/o damaging the fitting as last time I used a 3” long drywall screw and I thought that was good enough: read “I thought”.
14. With my setting the actuator screw longer, I had no “noticeable” boost until around 3k RPM and then just a little and then before I could blink the tach was pegged and I needed to shift. DAMN! THIS GIRL RUNS! I could not believe it! I had 200 millibar more than requested boost so no big deal there, but I had no fuel issue at all; I took multiple pulls and she was rock solid, it was weird though—it was kind of like there was nothing special going on until 3k and then it was time to shift. The power band isn’t very useful to me this way with the current tune, but likely it will act differently when I flash the new tune.
15. I am hoping it was an anomaly that the 3 bar sensor wasn’t reading boost earlier, as I am really curious what 24 PSI and more fuel (vs 18 PSI) will do now that I have things basically sorted out. If push comes to shove I will shorten the actuator rod a little bit and install a Dawes device so I can have power at less than 3 k. I will keep you posted.
16. I decided to see if the 3 bar sensor would work again; it read boost so I re-flashed the updated tune. Two minutes away from the house the sensor went "implausible" again, so I will wait until tomorrow to see why it goes from good to bad.
01-09-2017 Update:
The vendor replaced the bad 3 bar MAP sensor, and I got it installed without incident. I re-flashed my ECU with the new tune. After I significantly shortened the actuator rod I have no more over boost, just a lot of power at the push of a pedal. My tune provides 24 PSI altitude corrected and conservatively fueled exactly like I asked Mike to write it for me. The weather here is cold, rainy, and snowy so I can't really do a proper blast down the freeway to see just how much more power I actually have.
1. Engine starts losing power at higher RPM's: power band keeps getting shorter and shorter, but as long as she starts and gets me to work everyday I will wait until Winter Break to figure it out.
2. Along with power band getting shorter engine starts to hiccup: full power, no power, full power, etc., etc.
3. At this point anything over 1/2 throttle and engine feels like it died.
4. Suggestion is made maybe overboost condition is cutting back fueling: VCDS is only showing 300 millibar of overboost, not enough to cut fueling in software.
5. I replace the fuel filter in case it may be plugged. Not only was it not plugged but there was not not fuel at the lower edge of the the "tee" like there has been in the past.
6. Maybe the check valve thingy in the fuel sender is plugged. I drilled it out and re-installed it. That wasn't the problem either.
7. Strange noises are coming from passenger side of car, RPM dependent, most likely dying pump. I replaced the pump. That didn't fix the problem either.
8. Connected mity-vac to fuel supply headed to tank, minimal fuel, lots of bubbles; in fact enough bubbles for fuel to drain back into supply line
9. Took car for test drive in daylight with VCDS connected now I am showing correct requested boost and 845 millibar actual. This is an almost new 3 bar sensor that is now apparently dead. I removed it and flushed it with brake cleaner and it was still dead.
10. Now what? Re-install 2.5 bar sensor and re-flash original tune.
11. After cleaning and re-installing 2.5 bar sensor the real problem is now obvious: 800 millibar above requested; I guess there was a fuel cutting issue. All this excess boost doesn’t make any sense the car used to run strong and predictably and now this crap.
12. Put the car up on ramps and noticed something that did not make sense: the threads on the actuator shaft were missing, as in the shaft was as short as it could be W-T-F??? Apparently I did not spend as much time checking to see that the lock nut was tight as I did setting the lift at 3” and the stop at 18”.
13. I just guessed and set the thread length above the nut approximately 3/8” and took her for a test drive as frustration was beginning to set in and at the last second I decided to drill out the fuel pickup with the “proper” sized drill bit; the one that the biggest I could fit in there w/o damaging the fitting as last time I used a 3” long drywall screw and I thought that was good enough: read “I thought”.
14. With my setting the actuator screw longer, I had no “noticeable” boost until around 3k RPM and then just a little and then before I could blink the tach was pegged and I needed to shift. DAMN! THIS GIRL RUNS! I could not believe it! I had 200 millibar more than requested boost so no big deal there, but I had no fuel issue at all; I took multiple pulls and she was rock solid, it was weird though—it was kind of like there was nothing special going on until 3k and then it was time to shift. The power band isn’t very useful to me this way with the current tune, but likely it will act differently when I flash the new tune.
15. I am hoping it was an anomaly that the 3 bar sensor wasn’t reading boost earlier, as I am really curious what 24 PSI and more fuel (vs 18 PSI) will do now that I have things basically sorted out. If push comes to shove I will shorten the actuator rod a little bit and install a Dawes device so I can have power at less than 3 k. I will keep you posted.
16. I decided to see if the 3 bar sensor would work again; it read boost so I re-flashed the updated tune. Two minutes away from the house the sensor went "implausible" again, so I will wait until tomorrow to see why it goes from good to bad.
01-09-2017 Update:
The vendor replaced the bad 3 bar MAP sensor, and I got it installed without incident. I re-flashed my ECU with the new tune. After I significantly shortened the actuator rod I have no more over boost, just a lot of power at the push of a pedal. My tune provides 24 PSI altitude corrected and conservatively fueled exactly like I asked Mike to write it for me. The weather here is cold, rainy, and snowy so I can't really do a proper blast down the freeway to see just how much more power I actually have.
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