If something loose was going to cause KR...

[AutoEuphoria]

...what would be the best place to start looking?

I've had an issue with KR for a while now. It only happens at the high end in third gear and mostly through fourth gear at WOT. It's not detonation...AFRs/fuel pressure/BATs are normal or better than normal. So by best guess is that the knock sensor is picking up some noise somewhere and reading it as knock. My clutch might be slipping under heavy load...could this chatter be picked up as knock? I'm getting the clutch upgraded next week, so I guess I'll answer that one then. Or possibly an exhaust leak at the downpipe? I'm just trying to figure out where the knock sensor is, and what might be around it that might be giving noise that the sensor might be picking up and interpreting as knock.

Thanks for any help!

 

[creedns]

injector seal could be shot. does it hold steady til you let off the throttle? how much are you seeing?

 

[AutoEuphoria]

Yeah, it stays on constant...in 4th gear especially. It gets up there...like 6.0. I don't stay on the gas long when it does that, though.

 

[ReNaToMS3]

Mods?

If you have an intake or other breather mods, your ignition timing will most likely be high for those mods. Stock tune and Stg1 OTS maps from Cobb have a very advanced timing. If the car is stock, you won't face the KR problem so it must be something else. You gotta look for the problem, because there's one. As you know, WOT KR is BAD.

I had to adjust my timing under load by 4-5 degrees to get it under control. Might be worth a shot if you have an AP or other tuning solution.

 

[creedns]

constant while under boost sounds like the injector seal. can you make it register knock while revving during idle

 

[AutoEuphoria]

If it was the injector seal, wouldn't the AFR be higher than normal, and wouldn't I be able to smell fuel?

Also, I apologize for the ignorance, but where do I adjust the timing in the ATR software? Do you adjust both the low throttle and high throttle tables? Where did you start the changes (RPM/load)? How much did you change each value? Did you have a situation where the original value was positive, but your change made it negative? I just don't want to really screw something up.

 

[creedns]

you cant smell the fuel, but you can hear them making a popping noise while u r in boost.

 

[AutoEuphoria]

I honestly haven't heard any strange noises when the KR came around, but I will listen more closely next time. I can't get it to get KR at idle...usually only at WOT at the end of third and into fourth. Never in first or second, even at redline (besides the random partial throttle KR blips that is normal with this car).

 

[ReNaToMS3]

If it was the injector seal, wouldn't the AFR be higher than normal, and wouldn't I be able to smell fuel?

Also, I apologize for the ignorance, but where do I adjust the timing in the ATR software? Do you adjust both the low throttle and high throttle tables? Where did you start the changes (RPM/load)? How much did you change each value? Did you have a situation where the original value was positive, but your change made it negative? I just don't want to really screw something up.

Kay,

First make sure you have the latest version of ATR and your AP is updated. With the new load cap fix, you gotta update both. Make sure the "Max Calc. Load A/B" tables have 3.00 for load to make sure the new load cap fix is included in your map.

If you're having WOT KR, try changing the High Throttle table, from 3500RPM to 5500RPM, 1.5 load and up, 2 degrees down. From 5500RPM to redline, 1.5 load and up, try reducing by 4 degrees. The load parameters can be logged using "Calculated Load"/100. So if Calc. load is 150, on ATR it's 1.5. This is good to know because if you see more KR while logging, you can pinpoint excaly where to change timing by cross-referecing RPM and Load. Try changing timing in .5 increments after the initial changes. Low Throttle tables is used for CL operation.

If it changes to positive or negative, it doesn't really matter. I reduced more timing after 5500RPM because the KR sensor goes deaf @5700RPM, too much engine noise past that. If there's any knock past that point, the sensor doesn't register it and can't reduce timing, so the chances of your car blowing up is far greater.

 

[AutoEuphoria]

Thank you! I wish I could give out rep

 

[ReNaToMS3]

NP, just remember the reduced numbers i said are from stock timing. If you got a Stg2 map instead of Stg1, the timing will already be lower so it's good measure to lower a little less than what i said, until you find a good balance. You can compare stock vs. your map by selecting "Stock Mapping" from one of the menus above. That will bring all the stock values for all tables. You can then open another ATR window and compare whatever table you like.

More timing=more power, and you would want to run as much timing as you could on the map, until you hit KR on a WOT run. That's where you reduce .5degrees and leave it at that. Takes some time but it's worth doing it. If you find yourself lowering timing a LOT (like 7-8 degrees), than your problem might be mechanical.

 

[MS3inDC]

correct me if I'm wrong, but isn't KR the ecu correcting timing to avoid knock. Isn't it just a measure of the amount of retard that the ecu uses to avoid knock?

I remember reading on this forum that having KR isn't necessarily a bad thing...

 

[SallySpeed3]

correct me if I'm wrong, but isn't KR the ecu correcting timing to avoid knock. Isn't it just a measure of the amount of retard that the ecu uses to avoid knock?

I remember reading on this forum that having KR isn't necessarily a bad thing...

Partially true, our ECU will adjust timing to achieve better mpg's, and it you're monitoring KR it will show up as .35, .7, 1, etc. It usually goes away after only a second, this is usually only during cruising or moderate acceleration. If you're getting KR that stays constant and keeps building thats bad. And any KR during WOT is not good. Hopefully people more knowledgable will chime in cause I could be wrong.

 

[creedns]

kr while cruising and takin off is normal, generally .4-.7. i know dudes that see 8+ counts of knock and dont sweat it, but for the most part anything over 2.0 is not good, and wot knock is a big no no