Hi Guys,

So I have been playing around with my cruise timing to get better MPG and all of a sudden I am hitting HIGH knock counts (think 10+, sometimes 17) at cruise... WOT is ok!

Is it possible a bad batch of fuel will cause knock @ cruise but not at WOT?

Cheers
D.

 

Oh I forgot:

I have since returned the timing (the whole map) to stock and the knock is less, but still high (ie 6KS) for cruise.

 

you probably went too lean, try retarding timing in those area.....

 

cruise is running stoich - ie 14.7:1

plus i've put the timing back to stock and it still knocks...

 

From my testing I found heat soak to cause knock during cruise.

Do you have standard air box with scoop or open filter?

 

stock as a rock...

i filled up from my regular station tonight, so hopefully I will get a clean log tommorow

 

My data shows that there where times during my tuning where I would have only midrange knock, and no knock in the top end.. Always on 91. Varying between Sinclair and Chevron. They don't have Shell here, or it would be Shell all the way. Utah has just as bad if not worse 91 than California.

This weekends 400 mile trip I had little to know knock(1 count here and there) in all my power band, and then I come back to Utah, and put another tank of 91 in, and I start to knock a little bit in the mid(1-2 count @ 2.5k~3.5k), more so than the Petrol purchased out of state at the same level.

 

is it when going from vacuum to about 0-5psi u get the knock tephra?

 

update - filled up from my regular and still get KS spiking to 11 sometimes...

still ok during WOT thou...

I am going through the knock code on the X now, trying to see if there are any hidden variables that might be being introduced..

I am thinking maybe an ECU reset will fix it ... keeping in mind the X ECU doesn't reset like the IX ECU after a reflash!

 

At what load are you seeing this? I remember someone saying how noisy the motor is in vacuum but it shouldn't be an issue. I would assume there is a reason even mitsu ignored noise under a certain load.

 

70-110

trouble is it was fine b4...

 

like you mentioned, i would start with resetting the ECU and see if it fixes it and if it comes back.

 

mmm...

btw it all started after two events:

1) installed 3port
2) hit boost limit fuel cut

Now I have un-mounted the 3port from the chassis just incase it was clicking->knock..

Could I have broken anything by hitting boost cut???

 

I have experienced boost cut on numerous times in numerous cars, of course none in an X. I have yet to see any permanent damage. Unless it put the ecu in a safer mode that is causing issues?

 

im pulling knock in roughly the same load im going to tone down the timing and see if it helps.