Project Lex

[Matt D.]

Is it an ignition or fuel problem, or a problem at the root of both systems? If it could be one or the other but not both, have you thought about working backwards straight from the ignition or injectors?

[Halon]

I have unhooked the ignition, so the ignition is being run by the stock ECU again, and MS is only controlling the fuel. MS is losing sync, which is all driven off the Cam and Crank position sensors. MS needs to see 24 crank pulses, then 1 cam pulse, then 24, then 1, and that's how it stays 'synced' with the motor. When it loses sync, it shuts off the outputs to be safe (so in this case, fuel) which is why you hear the hesitation. The sync error code I receive is 17 which means something like "wrong amount of crank triggers before seeing the cam trigger". Whether or not it's something in the hardware that is the issue, or a setting in the software, I am really unsure of. Support from the guru's are starting to fade little by little as well which doesn't help.

And here is a vid of the crank vs. cam square waves.
http://www.youtube.com/watch?v=kfUace3pZzM

[Halon]

OK well just took a wild stab and it seems to be 100 times better, although not completely taken care of. Since earlier some signs were telling me that the crank trigger was the likely cause of this, I decided to enable crank only filtering. I used the Tach Rejection feature, and set it to 30% as that was a value I had seen thrown around in the filtering documentation on here. And what do ya know, the issue seems to have 99% gone away. You'll see in this video that it still lost sync a couple times under WOT, but way better than before. I will play with filtering a little bit more and hopefully be done with this issue.

One thing I did notice was that in the composite log, the crank now shows up as a square wave instead of just a single edge as it did before. No idea what that means however.

http://www.youtube.com/watch?v=EZPwl3fj34I

[Halon]

Played with the filtering a bit. I have the global filter time now set to 5uS. That basically means, any pulse that is less than 5uS in length gets filtered out. Anything longer than that is considered good and is used. So basically goes off the assumption that good signals are long, and noise is short.

I then set the rejection percentage to 70%. That means that it predicts when it should see the next pulse. So anything that happens within the first 70% of that time gets ignored. For example say it predicts it'll see the next pulse in 100ms, it'll wait for 70ms until it even starts looking for it again. So any noise that is occurring in the first 70ms is completely ignored.

Car is running like a champ!!! Goint to hookup the ignition again and make sure she's running good still. If so, I may start talking to Shane about getting a quick base tune before the turboing begins!!

[turbotalon1g]

^Awesome.

[Speedfreak]

Bman, the new MS guru.

[95talonracer]

NICE!! Turbo'd by dyno day?

[Murlo26]

Glad to hear you sorted it out...was getting worried there for a while. Looked like a tough little cookie of a problem haha.

[goodhart]

Glad you figured it out, cause that shit was way over my head haha!

[cmspaz]

I understood a lot of it, and I'm glad it was you doing it, not me. ;)

Good work sir.