My LCD screen project, boost, WBO2, Knock, etc

**fastbikes76** · 08-28-2013, 10:12 AM

HI,

Just fitted this lovely bit of kit and im very impressed with it !! I do however have a few teething issues I need your advice on please

1.) boost control

The car makes the required boost fine, BUT it cycles very badly when building boost in higher gears like 3rd onwards, its almost as if i'm lifting on and off the gas constantly. I am using the Mac valve as recommended and have the connections the correct way around going from Google.

2.) Screen

The screen refresh rate seems very slow on mine and I have had to drop it too its lowest setting of 2 to actually get 'live time' information. It also sometimes slows down so bad that if I turn the dial it can take upto 2 seconds to change to next menu.

3.) connection

The car connects perfectly something and then will drop out and attempt to reconnect 4 times randomly for no reason. Once its dropped out it wont actually connect again until car is restarted. Having checked all the settings I am happy they are correct for my car...saying that Evoscan used to do something similar before too so perhaps this is more of a car issue ?

4.) Knock

The screen with the WB, BAR and Knock registers no knock and the audible alarm is set to 5, however if I go to the peak memory showing BAR and Knock it records 28 counts of knock. I know 100% fact its not knocking as I'm running 30% methanol and usually 1.1bar, today I was testing at only 0.75 and recalling a peak of 28counts. No audible warning and no live count of knock shown ?

The car in question is a 97 JDM GTO SR which uses the exact same ECU as your federal spec 3 plug ecu's.

Any help would be greatly appreciated.

**BlackStealth** · 08-28-2013, 02:48 PM

You can double check your mac valve installation by referring to the online manual.
http://www.lcdbc.xp3.biz

If you're using the feature called "-DC% per Knock", it will pull back the boost, and give you that pulsating feeling (especially since you're experiencing false knock of 28). I would recommend setting this value to zero for now.

It seems about 5% of the cars out there (94+) have issues communicating with the ECU. Some have fixed this problem by addressing a grounding problem.

MUT communication has no error checking, so if noise is introduced into the communication channel a false positive would get tiresome. Nobody would like to see the screen flashing and an audible alert trigger on each occurrence. So the LCDBC will disregard a false positive but still make note of it (ie. Peak Knock). The LCDBC requires two readings (within a short duration of time) before it believes the results and trigger a warning.

OBD1 and MUT screen updates are fast. The only slow poke is the OBD2-MUT connection. Assuming you're using MUT, then this just means there's some communication problems with the ECU. The LCDBC will patiently wait for a reply from the ECU until it times out before it moves on. Many unsuccessful attempts will make the screen refresh appear slow.

**fastbikes76** · 08-28-2013, 03:44 PM

Originally Posted by BlackStealth

You can double check your mac valve installation by referring to the online manual.
http://www.lcdbc.xp3.biz

If you're using the feature called "-DC% per Knock", it will pull back the boost, and give you that pulsating feeling (especially since you're experiencing false knock of 28). I would recommend setting this value to zero for now.

It seems about 5% of the cars out there (94+) have issues communicating with the ECU. Some have fixed this problem by addressing a grounding problem.

MUT communication has no error checking, so if noise is introduced into the communication channel a false positive would get tiresome. Nobody would like to see the screen flashing and an audible alert trigger on each occurrence. So the LCDBC will disregard a false positive but still make note of it (ie. Peak Knock). The LCDBC requires two readings (within a short duration of time) before it believes the results and trigger a warning.

OBD1 and MUT screen updates are fast. The only slow poke is the OBD2-MUT connection. Assuming you're using MUT, then this just means there's some communication problems with the ECU. The LCDBC will patiently wait for a reply from the ECU until it times out before it moves on. Many unsuccessful attempts will make the screen refresh appear slow.

Just triple checked mac valve and its correct.

I did have DC% per Knock set too 0.5% but have no zero'd that. All other setting are as per new unit setting (including the duty cycle)

The power wire is connected to the stereo power and the earth to the centre consol...is it likely one of these is not suitable and is the reason for the random false knock counts ? As I say they are only recorded in the Peak section and shows no knock in the actual live count. I know it is not knocking or even reading knock on Evoscan as im literally running half my usual boost while setting up

I have my car set to MUT as OBD2-MUT doesn't work..i presume that's correct ?

Many thanks for your help and patients

**BlackStealth** · 08-28-2013, 04:37 PM

OBD2-MUT isn't supported on Euro ECUs. I wouldn't be too concerned if you're really knocking, I'm betting it is all false knock because of communication problem, and that certainly is your issue.

As for grounding, I would suggest using the same ground point as the ECU, like the ECU bolt. Some have noted that when the low/high voltage fuel relay kicks in, that's when the electrical noise problem begins. Somewhere on this thread (probably around page 50s) I have pictures of factory ground point that needs checking.

Also if the stock ECU does not receive a valid request within 2 seconds (or is 5 seconds?), it disconnects.

**Unlogic** · 08-28-2013, 05:11 PM

I'm seeing similar issues as fastbikes76 on my 1996 eurospec TT. The unit works fine for about 5 minutes then gets disconnected from the ECU and no matter how long I leave it on it never manages to reconnect. However if I cycle the power to the LCDBC with the engine still running it reconnects just fine again until it disconnects again after a few minutes.

I'm also seeing the same false knock readings of up to 27-28 counts during light load and cruising but it's not setting of the alarm which I have set at 8 so I presume it's false knock.

Here is how I installed in my car:

One of the switches next to the display controls the power to the LCDBC so I can restart it easily for now.

I've noticed that the unit randomly slows down before disconnecting. I've also noticed that on the screen showing max knock and boost I can see evidence of graphics corruption with random pixels (often one or two) lighting up in the lower line of the display to the right of the text if the unit has been on for a while. It only affects that screen which makes me suspect that it could be a software issue.

If it's any help I could film the display while I take a short drive, showing you the whole cycle of power up, successfully connecting, working fine, slowdowns, graphics corruption, disconnect, failed reconnect attempts, power cycled, successfully connected.

Could it be that our Eurospec ECU communicate slightly different in some way causing software issues?

Apart from the issues above I must say that I'm really impressed with this product both the quality of the components and the functionality is really great when it works. I replaces a whole bunch of gauges and make it so much easier to keep an eye on the ECU parameters while driving.