Knock problem with ECMlink data! Please HELP!

[throughfaith323]

Hey GVR4.org,

I have a knock problem and was hoping someone here could help.

MODS:
-EVO 3 16G (18psi)
-EVO intercooler with 2.5" piping
-BC 272 cams
-EVO/3g maf
-FIC 950cc injectors
-Base pressure: 44psi
-Global fuel: -56.6%
-Deadtime: 360usecs
-Walbro 255
-ECMlink

After installing the E3-16g, along with a bunch of other mods, I wanted to try and tune the car with a few pointers from my friend(first time ever trying to tune)....

Here is what I did:
1. Set the fuel adjustments for the 950cc injectors.
2. Brought the timing table to zero.
3. A few other things.
4. Went for a drive and logged a 3rd gear pull.

The AFRs seemed to be pretty good at WOT so my method from here was to keep on advancing timing until I noticed substantial knock popping up. I could not advance timing even 1 degree without making the knock increase. There is something wrong here correct? Timing advancement should increase with rpm's and I seem to have the opposite effect.

I thought my knock sensor was shot when I looked at it and the goo was completely missing. I switched it out with another knock sensor I had lying around and this did not change a thing. I thought for sure I had a bad knock sensor.



Below are screen-shots of the 3rd gear pull "LIVE datalog", timing table, and fuel adjustments respectively. Maybe something sticks out from this data that could point me in a certain direction?






Where should a go from here? Any suggestions would be very much appreciated!!

THANK YOU!!
Ed

 

[spooling92vr4]

can you post a log so we can see your settings?

 

[vtecds1]

Not sure on a solution but just by looking at your log, the coolant temp seems to be pretty high.

 

[throughfaith323]

Quoting spooling92vr4:
can you post a log so we can see your settings?



how do I post a file? I can give you screen shots of anything that might help.

thanks!

 

[throughfaith323]

Quoting vtecds1:
Not sure on a solution but just by looking at your log, the coolant temp seems to be pretty high.



I thought our cars run about that hot? What is normal for them?

 

[beaner]

Between 189 and 206 is full timing. From 206 to 224 the ecu pulls one degree. Over 224, two degrees.

 

[throughfaith323]

^^Quote:
Between 189 and 206 is full timing. From 206 to 224 the ecu pulls one degree. Over 224, two degrees.



Hmm... that's definitely a problem for me then because that entire 2->4th gear it was 206degF then 210degF. THANKS for the info Beaner!!

That shouldn't be enough degF to cause detonation, then causing knock, at high RPM though would it?

EDIT:
Possibly enough to mess with the knock sensor?

 

[beaner]

Just figure out a way to post the log.

 

[WaRrIoRs16]

Found this a while ago when I was trying to post a log. click

 

[WaRrIoRs16]

It looks like your a little lean for running gasoline. In your first pic your wideband shows you at 11.8 AFR, I believe you should be targeting 11.0. Also your AFRatioEst looks dreadful. You probably have some airflow reading problems going on because it is showing that your flowing much more air than you actually are. Is your Base MAF type set to evo8/3G? If not, that could cause some problems. Lastly, boost leaks perhaps?

 

[throughfaith323]

Quoting WaRrIoRs16:
Found this a while ago when I was trying to post a log. click



dang! thanks for the info.

 

[throughfaith323]

Quoting WaRrIoRs16:
It looks like your a little lean for running gasoline. In your first pic your wideband shows you at 11.8 AFR, I believe you should be targeting 11.0. Also your AFRatioEst looks dreadful. You probably have some airflow reading problems going on because it is showing that your flowing much more air than you actually are. Is your Base MAF type set to evo8/3G? If not, that could cause some problems. Lastly, boost leaks perhaps?



-I thought the optimal stoichiometric mixture for gasoline and turbo was 11.6-11.8 at WOT?

-I was told that in ECMlink the "AFRatioEst" would not be near accurate. Is this not true?

-Quote:
You probably have some airflow reading problems going on because it is showing that your flowing much more air than you actually are.


What should the airflow amount roughly be at Xrpm with a E3big16g?

-I do have the base MAF set at evo8/3G

-I looked for boost leaks some time ago. its been a while so I will definitely check them when i can get the tool from a friend or make one myself.

 

[gramkrakr89]

I think the stock ecu tries to hit 10.something AFR at WOT... i think... right?

(BTW, the estimated AFR in ecmlink is way off base because of the calculation settings in the logger... it's not actually that lean, the pc just calculates that value based on data that you enter in the "fuel" settings somewhere...)

EDIT: actually, it's in display preferences for AFRatioEst on the log graph itself, for older firmware versions

 

[beaner]

11:1 is pretty common I think. Afratioest will be off if your global fuel, deadtime, and/or maf settings are wrong. If your new knock sensor is tightened too much into the block, it can give a false reading. I tightened mine with just the weight of the ratchet and a dot of thread locker for peace of mind.

 

[throughfaith323]

ok cool. thanks for confirming the AFRest thing. lets just hope my wideband is reading right and nothing is screwing that up.

 

[throughfaith323]

Quoting Beaner:
11:1 is pretty common I think. Afratioest will be off if your global fuel, deadtime, and/or maf settings are wrong. If your new knock sensor is tightened too much into the block, it can give a false reading. I tightened mine with just the weight of the ratchet and a dot of thread locker for peace of mind.



- Hmmmm...can anybody confirm that the deadtime I chose for the 950s is correct please?

-I read about the knock sensor issue somewhere. I thought mine was bad and I replaced it with one from another motor I have. The sensor seemed to be pretty new. I thought for sure it was phantom knock and this new sensor would fix it but i was wrong. I installed the "like new" sensor and applied the right torque (It was an odd number if i remember correctly. something really low. I will double check this though and make sure its good. maybe i'll try your method /ubbthreads/images/graemlins/smile.gif.

 

[throughfaith323]

So today I checked my spark plugs to see if any of them looked out of the ordinary. They all looked the same besides cylinder 4 which was wet. I think its just wasted gas from leaving it in the head while checking the others for spark. All sparked fine from what I could see/hear during the day. Does anybody here have any experience/know how to "read spark plugs?" These pictures were taken after cruising for 4 minutes on the way home from some pulls:



Now as far as the pulls. The outside air temps were probably about 10degF cooler than yesterdays logs. This allowed my coolant temps to stay much lower. After doing a pull with the same settings as yesterday(shown in pictures from my first post), the knock was a bit lower (shown below). I then decided to see what would happen if I added a degree of timing across the board, and then another degree of timing across the board. The knock got worse each time(as expected). During all this the coolant temp remand the same as the first pull. I am still going to address my abnormal heat conditions, and I know it doesn't help my problem, but at least we can rule out the coolant temps causing my knock. I thought that would be kind of pushing it, but I did not want to rule it out.


There is one thing I've noticed in mostly all of my logs from the very first time I started dealing with this issue. There is a point where my knock hits a maximum and then starts to go down. This should happen as the car is pulling timing to prevent the knock, correct?. However, for the last 700 or so rpms of my pulls, the timing is increasing and the knock continues to go down. I'm not sure if this helps get down to the problem, but figured I would point it out.

Thanks for the support guys!
Ed

 

[beaner]

Quoting throughfaith323:
can anybody confirm that the deadtime I chose for the 950s is correct please?


Not without a log. That deadtime seems common for those injectors so it's probably close. The ecu uses voltage and many other values to determine deadtime. Therefore, each car is different.

I noticed you're at 44psi base fuel. It should be set at 37psi, as that is what the ecu is expecting.

 

[vtecds1]

^^^I agree with the dead time being different for every car. The ones you see posted on the Link board are just starting points. You have to fiddle around with the numbers. I thought I had mine all set, but it was over 100 off.

Also, my tuner was getting small counts of knock at over 6500rpm. He messed around with the timing and it was still the same. Check the plugs and there were all good. Phantom knock seems to be the culprit on my car.

 

For what it's worth, when i changed my thermostat to a 160 from the stocker and added 2 12" fans in front of my radiator i was able to pick up about 7-10* of timing just by lowering my coolant temps.