HMatt

iTrader: (1)

The BCS is fighting me. It seems to have a mind of it's own. Hopefully you ECU Gods can shed some light on the subject. Everyone I have talked to and have dealt with is stumped.

THE PROBLEM:

I'll typically get around ~14psi unless the WGDC is over 92-93%. Then it'll shoot up to ~25psi after that, then by ~97%, it'll shoot up to or over ~30psi. Not much room for a tune in there. PLUS, after about 6700 rpm to redline, the boost will increase to about what it's supposed to be based on WGDC...

CURRENT TROUBLESHOOTING:

1. Originally I had a GM 3-port w/the resister soldiered into the pigtail. Resistor and all was removed and a Greddy 3-port was installed. No change.

2. ECU was swapped with a known good ECU. My rom flashed into it. No change.

3. Different ROM versions flashed to check for bad driver. No change.

4. Wire from ECU to BCS re-ran. No change.

5. Manual Boost Controller swapped in. WORKS BEAUTIFULLY!

REASONING:

1. With ECU and BCS replaced, the issue has to either be wiring or ECU programming.

2. Because MBC works, the car is mechanically sound.

FUTURE STEPS:

1. Re-run positive BCS wire.

2. Re-run ECU ground wire.

3. Tom Cruise Voodoo Magic.

Q&A

1. Why don't you just stay with the MBC?
First, that's the easy way out. Second, I have a methanol injection setup and I need the BCS to function properly because of the fail-safes.

2. Did you check all your connections?
YES! And soldiered-in all connections instead of using crimp connectors, then put heatshrink over the connection.

3. Mods?
2005 VIII MR originally purchased in Hawaii
Greddy BCS
Tephra V7 96530706
BBK Full Ported w/FP Anti-surge compressor housing
Dejon Tool intake pipe
Blitz SUS Kit (big *** air filter)
AMS ver2 intercooler
ETS stock route full intercooler piping
HKS 280 cams i/e
Perrin 3" downpipe
Perrin HFC
RS-R GTII Catback
Sun Hyperforce Ignition
Sun Hyperground system
Ported exhaust mani
Invidia o2 housing

4. Who's your tuner?
Scott Gray on Road Race Engineering's Dynapack.

5. Can you send me or post your ROM/EvoScan logs?
PM me your email and I'll send it to anyone who might legitly be able to help since I respect the a fore mentioned tuner and will not post his work for the world to see.

6. When did the problem begin?
According to all the copies of every single ROM that has EVER been flashed into my ECU, it appears to always have been there, even with the stock ROM. I am the second owner and the first to do any tuning on the car.

ETS Michael

iTrader: (91)

I may have missed it, but it had issues with the factory solenoid as well?

HMatt

iTrader: (1)

I did have it tuned a bit when it was still on the factory ROM/solenoid. The boost didn't seem to behave any differently than when I was 100% stock. That was before I got a Tactrix cable and started to really look into things though so I can't be sure.

The only thing I can be sure of is that I had the same problem with the GM 3-port that I do now with the GReddy piece. So I don't believe the solenoid is the issue.