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integrosse
10-01-2008, 08:26 PM
Got an 01 with Unitronic chip (stage 1+ set to push at 18 psi) and hi-flow cat + downpipe and the car will not boost correctly half of the time. Example this morning the car was only spiking up to 12 psi and holding 10 until I turn off the car. Tonight try it again and it was spiking up to 18 and holding around 15 psi until I turn off. It is always like that. Did some test with vag-com and no code came out. The maf seems okay and I don't really suspect any boost leaks. Also the dv is brand new 710n. Could it be the n75 that is bad? My mechanic told me that if this would be the case then I would have a cel.

redflagquattro
10-03-2008, 08:36 AM
i have the same software and im trying to figue this problem out also..the boost is so damn inconsistent and i dont get it..im going to try changing my n75 and if worst comes to worst i may have to go mbc or ebc to get it to boost more consistently.

integrosse
10-03-2008, 02:45 PM
i have the same software and im trying to figue this problem out also..the boost is so damn inconsistent and i dont get it..im going to try changing my n75 and if worst comes to worst i may have to go mbc or ebc to get it to boost more consistently.

Please let me know if this has cure the problem. I have logged on Ross Tech block 115 & 118. I found out that the boost request& actual is 10 psi so from my understanding something might be wrong with the cpu or flash program. The block 118 was showing the boost duty cycle to 71.4% at highest. I not sure what this exactly means so if anybody have an idea please let me know:




Group C: '118
Engine Speed- Air Temp In -Boost Duty- Actual Boost
TIME 740-6800 RPM <=110ーC Cycle 0-100%
STAMP /min ーC % mbar
1.41 2440 39 70.2 1560
2.72 2720 39 61.2 1650
3.93 3040 39 60.4 1600
5.23 3360 39 63.9 1650
6.45 3640 41 63.9 1680
7.74 4000 42 64.7 1670
9.05 4360 45 67.1 1660
10.37 4680 45 67.8 1690
11.68 5040 48 67.5 1680
12.89 5360 50 67.1 1630
14.2 5640 51 69.8 1590
15.5 5920 54 71.4 1610
16.91 6240 56 0 1620
18.22 4840 51 0 1080
19.61 3440 49 0 1050
20.92 1920 48 0 1040
22.33 1040 47 0 1020
23.74 880 46 0 1010
24.94 760 46 0 1010
26.36 800 45 0 1010
27.77 800 45 0 1010
29.06 800 45 0 1010
30.38 800 45 0 1010
31.78 800 45 0 1010
33 800 45 0 1010
34.49 800 45 0 1010
35.7 800 44 0 1010
37 800 44 0 1010
38.31 800 44 0 1010


Group B: '115
Engine Speed Engine Load Spec. Boost Actual Boost
TIME 740-6800 RPM 15-175%
STAMP /min % mbar mbar
1.01 2360 100.8 1600 1390
2.32 2640 128.6 1650 1680
3.52 2920 126.3 1640 1610
4.73 3200 134.6 1650 1660
6.05 3560 136.1 1660 1710
7.34 3920 130.1 1660 1660
8.65 4240 130.8 1670 1660
9.87 4560 133.1 1680 1660
11.18 4920 137.6 1660 1690
12.48 5240 133.8 1620 1640
13.79 5560 131.6 1590 1590
15.1 5840 129.3 1600 1600
16.4 6120 125.6 1560 1600
17.8 5280 13.5 980 1110
19.13 4000 14.3 980 1050
20.52 2320 14.3 980 1040
21.93 1080 17.3 980 1020
23.32 1000 12.8 980 1010
24.54 800 14.3 980 1010
25.85 800 15.8 980 1010
27.26 800 15.8 980 1010
28.66 800 15.8 980 1010
29.96 800 15 980 1010
31.37 800 15.8 980 1010
32.58 800 15.8 980 1010
34.02 800 15.8 980 1010
35.3 800 15.8 980 1010
36.6 800 15.8 980 1010
37.91 800 16.5 980 1010

redflagquattro
10-10-2008, 05:46 PM
Thats pretty interesting what you found out with the actual vs. requested boost..i wonder if that is really the case? Yeah mine is so damn inconsistent, and it doesnt seem to like full throttle..it seems to pull so much more boost at part throttle, and i can sometimes pull 23 psi in 4th and 5th gear, and it seems to not like boost in 1st and 2nd. It is really messed up it runs good when it wants too; i had a j valve in there and i swapped it out witht he stock c but it really didnt make too much of a difference. Also i dont know if yours does this too, but sometimes it will hold lets say 20 psi for a second or two, and then it will smack to 15 super quick..there seems to be something wrong with the file and it wont hold boost correctly. I want to try and screw with a boost controller, but i honestly may try a different chip and see if it that is really the case.

integrosse
10-23-2008, 12:26 PM
Thats pretty interesting what you found out with the actual vs. requested boost..i wonder if that is really the case? Yeah mine is so damn inconsistent, and it doesnt seem to like full throttle..it seems to pull so much more boost at part throttle, and i can sometimes pull 23 psi in 4th and 5th gear, and it seems to not like boost in 1st and 2nd. It is really messed up it runs good when it wants too; i had a j valve in there and i swapped it out witht he stock c but it really didnt make too much of a difference. Also i dont know if yours does this too, but sometimes it will hold lets say 20 psi for a second or two, and then it will smack to 15 super quick..there seems to be something wrong with the file and it wont hold boost correctly. I want to try and screw with a boost controller, but i honestly may try a different chip and see if it that is really the case.

Did you change the N75 valve? I notice that when I stop the car for about 5-10 minutes and than take it back it boost 14-15 psi for the first approx 5 min. of driving and then it won't boost more than 10 psi. I didn't have a chance to get it check to my mechanic but from what they think by phone is that they might be a boost leak and the reason that it boost correctly when a start with the car is that it reset the cpu until it see the leak and then it won't send more then 10 psi. Will have it check and let you know.

Seerlah
10-23-2008, 12:43 PM
Hope this thread (http://www.audizine.com/forum/showthread.php?t=241977) helps. Or maybe you have one massive boost leak.

integrosse
10-23-2008, 01:01 PM
Thanks for the help but I have big doubt that this is my problem because I also scanned the Group 3 and the throttle is at 100% and I'm DBW so I don't have a throttle cable.

redflagquattro
10-23-2008, 04:29 PM
yeah i changed the n75 back to the stock c valve and all it really did was lower the boost a bit. But one thing that i noticed that is interesting..i put a mbc in place of the n75 and set it to about 12psi, and the car feels so much more consistant at lower boost. I cant explain this i dont know what it means. I am going to change my plugs and run the the n75 again and see what happens. But if the plugs dont change anything im guessing its the tune, i dont know what else it would be, i cant seem to find any leaks anywhere.

redflagquattro
10-25-2008, 05:53 PM
changed the plugs (BKR7E gapped to .028) and the car is now about 85% more consistent, but it still doesnt seem like it is boosting how it should.

But i found a thread and it seems that a bunch of ppl are having similar problems but still have not pinpointed it http://www.audizine.com/forum/showthread.php?t=86604&highlight=glowing. Read the entire thread.

integrosse
11-04-2008, 12:28 PM
My mecanic had a look for 2 hours this morning and he couln't figure why this is happening. What we know is that the car is definitely going in limp mode after few minutes of re-starting the car. The only thing that he saw that could possibly be the cause is the O2 secondary cel that came on and putting the car in limp mode but this is not suppose to affect it. The only reason why this could be possible is because of my computer which is an M-Box and it is taking this value in consideration in order to work properly. We have reset the code and restart the car and so far it is boosting to about 14-15 psi so I'll check to see if ever it get in safe mode again for the cel code.

maxspeed
11-04-2008, 01:25 PM
slap a diode on that bitch and see if it goes away

integrosse
11-07-2008, 06:20 PM
slap a diode on that bitch and see if it goes away

I'm not too familiar with that diode thing but I will have to take a look. The car is back in limp mode again and it is not showing any code when I scan it. I guess I'll just check get it flash back to stock. I'm tire of scratching my head for this thing.