PocketLogger Graphs...Knocking only on take off?

[EagleTalonTim]

Completely edited

The problem I have is that from a dead stop in first gear (A/T transmission with push button shifter) if I mash the pedal to the floor, the knock (sometimes) instantly goes up to 43 counts of knock and will dwindle down unless I let off the gas and get back in the throttle, then it will go straight to 0. I did five 3rd gear pulls and I had 0 counts of knock each time. One other thing is that in the morning while still in limp mode, when I take off, there is a solid stream of black smoke pouring out the exhaust until it is warmed up.

Here is my setup :
Brand new 8mm wires and NGK BPR6ES plugs gapped at .28
Brand new Bosch O2 sensor
Brand new Knock sensor
Stock fuel pump (no rewire)
450 injectors with M/T ECU to run the injectors
MBC set at 14psi
Stock 13g turbo (came with the auto tranny)
One very small boost leak around the BISS screw that starts around 8psi
Hacked air can (MAF is still intact)

Please help!!!! I have been fighting this for weeks

 

[tbonitz301]

You need to go to digital tuning, inc. and download plviewer

 

[EagleTalonTim]

I just finished downloading it and now it says Not a valid PocketLogger file. Did I do something wrong?

 

[tbonitz301]

Ok man bare with me here it's been a min. I believe you need to convert the plviewer file to a .jar file before you save it. I remember it being a pain in the ass, but i was pretty well computer illiterate then

 

[EagleTalonTim]

ok, got it here are the graphs of 3 different logs with the same setup. Just went on a test drive and recorded these.

Boost running at 14psi

 

[spyderturbo007]

Although pretty, those graphs don't help at all. You'll need to post the raw data for us to be able to help you out.

 

[tbonitz301]

Yea once you've opened up your log file. Click on windows, and then data. This will give you your raw dataDamn i wish i had a 1g

 

[EagleTalonTim]

ok, hope this one works :

http://i78.photobucket.com/albums/j103/eagletalontim/personal/data-4-6-08-1.gif

 

[kmoore]

Are you knocking while cruising?! Kind of looks that way....

 

[EagleTalonTim]

sometimes it does. Most of the time on take off, I have to ease into the throttle so that my knock count does not go up to 43 and retard the timing in the negatives making the car extremely slow.

 

[spyderturbo007]

Have you checked the knock sensor for goo leakage and correct torque?

 

[EagleTalonTim]

yes, the old one did have a little goo, but I went ahead and replaced it. It still shows the same count as the old knock sensor.

 

[EagleTalonTim]

anyone know where I can find the torque specs for my knock sensor?

 

[EagleTalonTim]

I am guessing no one know what could be causing any of my problems I have been to every shop around here and they are DSM stupid so I really need to figure out what is wrong with my massive knock problem.

 

[spyderturbo007]

It's possible you're experiencing phantom knock. Personally, I don't know the torque specs for the 1g knock sensor, but I'm sure someone around here can answer that one for you.

Do you have access to race gas?

 

[tbonitz301]

+1 spyder i was going to say the same thing

 

[EagleTalonTim]

yeah, i can get race gas at the race track here but it is so damn expensive Is there any way to get rid of this phantom knock so that my take offs are not so slow? I am getting a minimum of 7 counts of knock on take off. Sometimes it hits 43 counts of knock.

 

[tbonitz301]

I believe dsmlink has an option where you can adjust the sensitivity of the knock sensor.

 

[dikdiamond]

I'm new to logging,and I'm getting knock at cruise similar to yours,but not as high(under 20 at it's highest). I have a new sensor to put in,and I'm hoping that will be the end of it. However I discovered that the bracket behind the intake manifold(that houses the vacuum lines)is loose,perhaps that could give me phantom knock? I'm thinking of removing it,my mechanic bypassed and removed the unnecessary lines.

Edit:after seeing pics of it here Knock Sensor it looks harder to remove than I thought(bracket)

 

[AL92]

There is no ifs you have phantom knock and you have it bad. I had it on my 92 talon and tried most everything to get rid of it. I changed out to new knock sensor no help. I did plugs, wires, coil,fuel pump, fuel reg ,injectors,etc. Finally went to chipped ecu with phantom knock elmination code. Car was way way faster without the phantom knock. For now you can disconnect the knock sensor. You will get a check engine light and you will default to think its 7 counts of knock. This is a couple of degrees of timing retard that will be constant. You could up the base timing a bit to compensate. If you are running premium and staying at reasonable boost levels then you should not hurt anything.

I did read about some guys welding the knock sensor end shut and I put in jb weld on one of mine .The 2g is supposed to be solid the 1g hollow. This didn't seem to help my 91 laser though. and new knock sensor also didn't help it.
You can leave knock sensor hooked up so you don't get code and then just tie it somewhere not in the block. This will give no knock and no code. Dsmlink can also wipe out phantom knock.

You can try 3g lifters sometimes they are the answer.I did not put 3g lifters in my current 91 laser or my 92 talon .
I also have a 91 auto talon awd turbo and it has no phantom knock at all. Put new knock sensor in it but even with old sensor no problem. Some cars have it some don't .So far had it in two of mine my 9 talon and 91 laser. Didn't have it in my 91 auto talon and didn't have it in my 2.4 97 talon engine swap.
Oh had a 90 talon awd also that didn't have it. It sucks bad and 43 counts is huge timing pulled.I think its dangerous and should be a safety issue. You are trying to get across the highway or something and the car acts like a 1 cylinder! Very very annoying.
Keep in mind that quite a few cars that were turbo never had knock sensors. As said if stay conservative on pump gas maybe 15 to 17psi if you have proper fuel support and run race at track then you don't really need a knock sensor.

 

[spyderturbo007]

Personally, I would never disconnect the knock sensor. As soon as you do, the ECU will dump you into limp mode, pull a crap load of timing and shoot for and AFR of about 7.6:1.

I was suggesting the race gas, because it's an easy way to determine if you are actually getting PK. If the knock goes away, then you know it's real knock.

 

[AL92]

From my experience on 1gs when you disconnect knock it went to either 7 or 9 COUNTS fixed and that is no where near as bad as 43 counts that is common with phantom knock 1gs. As for changing the afr to 7s have no evidence of that either but have not put a wideband on the car. The narrowband o2 readings are not going super rich either so not sure where the evidence for this is. Another alternative is to leave the knock sensor plugged in and move it to another location like on the firewall so it don't pick up the phantom knock.

Anyone that has not had this problem on their car or doesn't reallize they have this problem has no idea just how much power they are losing. It also makes it impossible to tune properly as you can't trust the knock sensor readings. Of course no knock sensor has problems as it is best to tune with wideband and watch knock readings.Especially as you push the car, lean it out or take out timing. But the solution there if you are going high on boost is to get chipped ecu with phantom knock code or dsmlink or aem ems as these tuning systems let you get rid of the phantom knock and still keep knock sensor for up high on boost. My 92 talon or 91 laser could get 43 crippling counts of knock off boost just leaving the lights. Don't need race gas to know its phantom! Anytime you have knock off boost its pretty much phantom.

These cars should have been subject to a class action lawsuit for this stupid problem.But most people didn't have scanners to see what was happening. It is as I said very unsafe to have alll your power go away when you need it to be there,crossing busy highway ,etc.
Its not just annoying its outright dangerous!

And I did have similar problem in my 96z28. Did similar things in that car,changed to new knock sensor,etc and problem would not go away. That car was NA so just run premium and took out knock with tuning. Car runs 1000% better and more consistent now.

Your choice but disconnecting seems to work not too bad but connected and relocated has some advantages too. You reach a point where you just can't afford to keep putting money into these cars trying to stop the phantom knock. Chipped ecu is likely cheapest real fix. Dsmlink and Aem are best fix.

 

[AL92]

And to be clear as crystal the above was in reference to 1g cars. Had no phantom knock problems in my 2gs including the one with swapping in 2.4 from hyundai.

 

[dikdiamond]

I had my lifters replaced with Top Line when I had the engine rebuilt last summer. If changing out my sensor doesn't work I'm thinking of mixing a few gallons of E85,and see if that will help. I've been researching about the pros and cons of that. I also filled up with gasoline from a different station,to see if that has an effect. I usually buy 93 from BP and this time I tried a Marathon. Link is down the road for me,and I'm not unplugging the sensor.

 

[spyderturbo007]

Anytime you have knock off boost its pretty much phantom.

I agree with you on that one, but I feel it's worth the couple dollars just to make sure. Stranger things have happened.