fast need help

[van460]

anyone who can help car has set all winter fast 160inj 521 wide band bank to bank system. on nitrous passes in second gear about 6500 the nitrous would kick off for a moment and come back on the rest of the way. 1st gear and 3rd gear did fine same place in 2nd two passes in a row looked at data log and it would pull timing till that point and go motor timing for a moment and pull timing again?? confused could a relay be faulty on and off.

 

[bobc455]

Not to sound elitist, but your post was very hard to read. Please add punctuation, etc., in the future.

Assuming your nitrous is controlled by the FAST, I would double check to make sure that you didn't exceed the RPM High limit, and that your TPS reading didn't drop below the minimum threshold... can you look at the log for those runs and check?

How do you know the nitrous was deactivated- just by the timing log?

-Bob Cunningham
bobc@gnttype.org

 

[van460]

help

Hey Bob - thanks for the quick response. Sorry about the punctuation. I'm a racer, not a writer. Did not mean timing log - if I said that. I meant data log showed me that the timing was being pulled while on nitrous. My motor timing is on my log screen and when nitrous is activated, it shows total timing as pulled out. During the pass, the timing was pulled out until that point and went back to motor timing. I checked TPS threshhold. It did not fall under activation point, and also, I did not rev the motor in its high RPM limit. Do you have any other suggestions??

Thanks.

Van

 

[Craig Smith]

If the nitrous deactivated, it had to be caused by one of four things - it dropped below the TPS threshold, it dropped below the RPM threshold, or the +12V enable signal went away. The fourth, as mentioned, is hitting the ECU rev limiter.

All of the first three can be checked on a data log. If you log a sensor called N2O enable, it should stay at 1 the whole time you have it enabled. It's possible that there could be some teeny tiny momentary blip that wouldn't show up on a data log, but that isn't likely.

Hopefully this will narrow down the things to look for. Hope this helps.

 

[van460]

thanks craig and bob

Thanks for the reply guys. I have a race this weekend, and the only thing that hasn't changed since I have owned the fast system is the N20 enable is on my data log screen, but I'm not sure if it's my laptop or what, but when I enable it, before I press return to data log, it is on 1, but after the pass and I review the data log, it is on zero through the whole run, but the nitrous does work. I put a new relay on for the nitrous, just in case it may be in the relay. I checked all the other three things you suggested, and everything was in its limits. Question though - will your minimum RPM deactivate the nitrous if it is hit, or does it have to hit the max and then deactivate? If you would like me to send you the data log runs, I would be happy to.