my question is if the ECU picks up a knock, does evosan 100% of the time also says so? Or does it miss here and there.

 

The knock sensor, like all the other sensors, are queried by EvoScan using the MUT protocol (extremely fast).

EvoScan logs what it pulls at that time. It IS possible for the knock sensor to quickly read knock and then go back to 0 but have EvoScan not pick it up, but if your laptop & cable are fast enough and configured correctly, it should be a non-issue since they log so friggin fast.

Besides, most people here will agree that knock is only issue when it compounds over 1 or more seconds, and is 2+ or more counts. Otherwise it could be considered phantom knock.

Someone correct me if I'm wrong.

 

ye i have also read that car that have 1-2 knock counts actually make more power than cars that have 0 knock, i could be wrong so dont hold me to it.

 

I wouldn't doubt that. But, I don't think they are actually making power from the knock ... they are just tuned a little more aggressively.

As it was said earlier, if the knock is so fast that the MUT logger doesn't catch it, you needn't worry.

 

it really depends on how many parameters you are logging. The more parameters you log through evoscan (or any logger) will slow down the response of the ECU.

It is possible, but unlikely that you could miss a knock event.

 

I agree.. it's a non issue typically, but it's a good question

 

+1.

As chris says though if in general you are worried about the speed of the logging you can increase the baud rate of the ECU from what I remember (search for it its in this forum)...and you could just get a better faster laptop

 

The less number of things you log the faster the sampling rates will be as well.

 

Yeah but he said that more or less verbatim above .

 

increasing the baud rate only works to a certain degree before you run into the physical limitations of the ECU hardware itself (which is quite old BTW)

 

I'm curious about something here.
In the factory service manual, it states in "Group 13A Multiport Fuel Injection" on page 12, there is a Diagnostic Test Mode II (Increased Sensitivity) using the MUT-II scan tool.
Does anyone know the workings of this? Does it increase the scan rate of sensor logging by the scan tool - or does it do something in the ECU? The manual states:
"Change the diagnostic test mode fo the ECM to DIAGNOSTIC TEST MODE II (Increased Sensitivity)." - which would lead me to believe the ECM is increasing its baud rate.
Note, it does say that something about this being emission related trouble only...but their verbiage leaves me guessing.

 

It's probably just referring to the fact that MUTII devices can read the ECU at full speed, whereas generic OBDII devices are slow

 

you could run a mains plug inverter in your car, most laptops on battery power only run at 50% cpu, with an inverter you can get more speed from your laptop and greater length of logging and still have your fav mp3s playing without fear of the laptop battery going flat after 50minutes

 

but I wouldn't worry about evoscan being slow, it is the fastest factory diagnostics on the planet especially if you have a 2001-2005 reprogrammable baudrate ecu if you want.. just log 5 dataitems only.. at 200samples per second thats 40 times per second per item! (Can electricity travel that fast? must be a damn fast and powerful ecu these cars have from factory) who in would ever want to upgrade to an aftermarket ecu is just mad... hehe.

 

I've been looking into the VOOMPC which is a mini-ITX form factor PC. Very low power requirements, and with the correct DC-DC power supply, it simply hibernates (which only draws current to power the memory). It also is car smart, in that it monitors the charging system, and shuts down if the car battery gets too low:

http://resources.mini-box.com/online...-HV-manual.pdf

This way, there is no real boot up time. It simply comes out of hibernation when the car is started. These things are tiny, and you can run a decent laptop hard drive in there with XP slashed down to bare minimum requirements. Just mount under the seat or in the glovebox. (dimensions 8.6"W x 10.4"L x 2.6"H).

Output the video to an in-dash DVD system, and you've got a perfect system for monitoring engine health. I would stash a mini 88 key keyboard in the glovebox, and possibly mount a mini trackball next to the intercooler spray switch.

http://www.mini-box.com/s.nl/sc.8/category.101/.f