can't figure out this KR

[NYSS guy]

Guys, I have pulled timing a few times, only run 93 octane, and I'm still getting KR all over the place. Can someone take a look at this scan, and let me know what I am missing. Especially look around frame 11300. This was just a ride to work, so a lot of it is highway driving, but I'm getting KR there too! Any input is welcome.

[GRRRR8]

It seems like your IATs and engine temp are high even when cruising. I dont know what the outside temp was, but your fan % seems low for the engine temp being 198.

[norm8332]

Is it running lean?

[shane]

ur iat are high that is clear...

ur commanded AFR isnt outta whack
ur o2 mv's are not outta whack


what are ur mods? just curious?


let me do some thinking

[NYSS guy]

Car is bone stock. I live in South Florida, so it's always hot out. It was 87 and humid during this drive. But, especially this time of year, it's always 87 and humid...at a minimum.

I don't have a wideband in the car yet, so I don't know 100% for sure if it's lean, but based on the narrowbands and fuel trims, I don't think it's lean.

[NYSS guy]

Anybody else have some thoughts? Or is this just a matter of a thermostat change, and a HSRK?

[shane]

u tune it yourself?
can u post the tune?

thats what im gonna need to see

[wreckwriter]

Anybody else have some thoughts? Or is this just a matter of a thermostat change, and a HSRK?

or some tweaking of the IAT table perhaps?

[shane]

the iat tables wont have anything to do with knock..

its based on the iat temp and what timing it will pull..

he is getting acutal knock..

[wreckwriter]

the iat tables wont have anything to do with knock..

its based on the iat temp and what timing it will pull..

he is getting acutal knock..

Yeaaaaa... my error.

[NYSS guy]

Here's my latest tune guys...and yes I'm tuning it myself. So I can make any changes you guys think would help.

When I tuned my SS, that thing never knocked...so I don't have much experience with a bone stock car having issues like this. Thanks all!

[shane]

well ur PE delay RPM is way too high...

also ur PE rate needs to be 1.0

id try another tank of gas too... ur getting alot of knock ive seen you have increased the timing tables but nothing too much

[NYSS guy]

I'll take a look at the pe stuff, but what you said about the timing is why I've been confused. I didn't think I was running too much timing.

Would the pe stuff cause the knock?

[shane]

its let you command the proper fueling(or close to it) under WOT
that delay is way too much

[shane]

that much knock just driving around though is crazy...

[NYSS guy]

That's what I'm thinking too? What I thought about though, wouldn't 5 degrees of KR be audible? The car sounds like it's running strong, the other stay I spun the tires on a 1-2 shift. But the IAT's are pulling timing, and I'm still getting KR.

Very confused.

[norm8332]

Believe it or not, when I was stock I used to get KR from hitting bumps in the road sometimes. The knock sensors are pretty sensitive by default.

[shane]

Believe it or not, when I was stock I used to get KR from hitting bumps in the road sometimes. The knock sensors are pretty sensitive by default.

yea i kinda noticed this to before i changed the tables a little bit.
seem pretty sensetive but i was getting like 1

[johnh]

Looks like knock to me.

So here's what I'd try, increase your PE fueling, the NB is reading 880-900, try to get it to 920-930 and see if it goes away. Alternatively, You could add more air to the MAF in the upper Hz areas (will also add fuel)..did you tune your MAF. Posting your tune as mentioned would help, as would listing your mods. Stock timing? If you've added timing, remove it as well.

If KR stops you were too lean/too much timing in PE (despite 12.65 being a usual good value to command).





You can also try some unleaded race gas (104 octane) to see if it goes away.

[NYSS guy]

Thanks John, that't the kind of guidance I was looking for. But, the tune is attached in a previous post. I did add some timing, but I didn't think it was much. I will get the NB's reading a little higher. I did tune the Maf, and getting LTFT's in the -1 to -2 range, I thought it was good. Car is bone stock, down to the air filter. I haven't had a chance to start modding yet.

[johnh]

Timing looks decent in the tune, its 1-2* less than what I run. Try adding some fuel and see. Those kinds of trims should be fine. Are you running 87 or 93?

I really only see KR usually on downshifts on tip in, or a tiny bit on Dod transistions. Its the KR at rpms over 5000 that's the worst.

Also, did you add air to the MAF? Make sure you scale the whole MAF curve not just the lower parts where your trims get set. I scaled my entire MAF up by I think 2-3% when I was just stock.

[NYSS guy]

More confusion. I went back to stock timing, and still getting KR all over the place. LTFT's are still in the -1 to -2.5 range. Should I scale the MAF to the -3 to -4 range for LTFT's? I have a histogram set up to log LTFT's vs. MAF, and I've made changes based on that.

Also, Shane you mentioned about the PE delay, I still have it set at the factory level...what are your thoughts on an rpm that makes more sense?

[NYSS guy]

Oh, Johnh, I am running 93.

[NYSS guy]

Just to keep everyone posted, I found 2 things that made some progress.

1-I forgot I modified the IAT spark table, so I put that back to stock settings.

2-As suggested, I added some air to the MAF table, and it cut the KR in half. I added 2%, so I think a little more, and I should be good to go.

Thanks for all the help Shane and Johnh!

[shane]

np man