Isnt the strange part that its occuring off throttle? If your switch over point is within vacuum and your tuning isnt correct obviously you will get knock.

 

hahah

the question/issue, is that the utec will pull timing uneccessarily when it repeatedly detects knock (even though it is under vacuum, low load)...i like the knock feedback feature, but dont want to have a retarded map after 5 minutes of driving because it is falsly detecting knock


sharif suggested reduce sensitivity...what would you suggest sharif...reduce knock count detection or actual sensitivity across the board, so , if i have 59 set, reduce to , say 50?

Thanks

TODD

 

i have mine set at 110 100 90 80 70 70 with no knock!!!


i dont think lowering them is such a great idea...


i know you dont want too high, but you want them to also do their job!!

 

It's false knock, caused by piston slap on decel or low load. J&S ignores the sensor until vacuum drops below five inches.

 

So we should ignore any knock that occurs when we lift off of the throttle?

 

Yes.

 

Can the UTEC be set to ignore the knock sensor, or adjust it's range of control, based on RPM and load?

 

The knock sensitivity can be user adjusted based on RPM range. I am not sure if UTEC has some logic that tells it to disregard knock sensor in vaccum or light load. Maybe Jermaine or Nathan can chime in.

The user could, if they wanted, completely eliminate the knock feedback correction, but its not advisable.

 

I would hate to disable it completely, but I also hate for it to register as knock when I left off the accelerator. Maybe I can get an upgraded version of the MPS software that ignores the knock count if under light load.

 

What is your knock sensativity, and the RPM at which this is occuring on decel?

Is it just one count? Set your knock count threshold to about 3-4 at this point, so the start knock on decel will not cause any issues for you.

 

It really happens throughout the band from 1500-6000rpm. It's usually only one count, and it doesn't do it every time.

If I get home from Chicago at a descent time tonight I'm going to take it out and bump them back up.

My knock count right now is 4. I've never actually seen it pull timing.

 

Yup, then it sounds like there is nothing to worry about. Nathan from TXS told me that the knock count, in UTEC terms, isnt a physical single knock event. It is a measure of knock severity. So a knock count of 1 or 2 is very very minor, inaudible knock...possibly even background noise.

 

Just for the sake of illustration I post the following:







That was after driving the car fairly hard for 20 minutes or so. I had a few lean spots that have since been richened up a bit, but I still don't think there was any 'real' knock. That 0% column is pretty full though...

I've recently adjust my knock sensitivity so I don't know the values off the top of my head.

 

so you have all of the datalogging software working ??? That's awesome...where is the link for this again? Any special instructions in getting an innovate wideband to imput A/F? I have a tuner pro on my way anyways, I assume the software can easily translate the utec log into this nice graph as well, right?

good job!

TODD

 

I never had any problems getting it to work!

www.mpsav.com

 

i thought you said u had to make the exisiting sodtware (that was for the subarus) modified to work for the vq35???

that wasnt the case? i thought you had been working on this???

TODD

 

The software allows you to select which vehicle you have. Since the 350Z wasn't on the list I tried each one and found that the EVO was basically dead on with the Z. There was one very minor difference it seems, but I don't even remember what it was. I think it had to do with a values label.

 

bear with me here...i have downloaded the software...now what steps do i go through to make this work?

i hook up hyperterminal, then open software..then....? thanks for the help!

-TODD

 

Actually, you don't need hyperterminal to make the software work. In fact, if Hyperterminal is connected to the UTEC then this software won't work (since they both use the same serial port).

You should be able to simply open the software, select the com port for your UTEC and set it to 'EVO' mode. Then hit 'connect to device' and it should talk to your UTEC. Then, you can work on the wideband side of it. I have the AEM, so I selected the AEM option and put in the com port I was using and it works great.

Also, just so you know, the UTEC has to be in the top most menu when you start this software up, so the software can put the UTEC in to logging mode. This gave me hell at first, as I would exit hyperminal with the UTEC in the programming screen, instead of the menu screen, and then the MPS software wouldn't display data for the UTEC.

 

Thanks for the explanation...so I just tried it , couldn't get it to work, I access the UTEC from hyperterminal, then back out as far as I can until I am in the main menu screen...

then I select "connect to devices" on the MPS Utec logger..and it says it connects (i had to go through a few com ports to see which one it would take)...I can not see any of the gauges ion realtime of the datalogging map trace events....so I am not connecting...

any ideas?

I have it set to "EVO 8 UTEC" mode and everything...no luck

Thanks
TODD