Trouble logging w AP

I tried three times today to run a 3rd gear pull data log for my first revision of the infamous basemap....it would initiate and then start logging, but a few seconds into my pull it would have trouble communicating with the ecu...any ideas on why I'm having trouble?? I tried repeatedly, and I got the same message. Seems to be only having trouble logging while In he middle of a WOT run...input appreciated! Thanks!

yeah, this used to happen to me. no one's found a definitive solution for it yet.

 

some believe it's the cable being susceptible to noise and voltage spikes during a WOT run. others believe it might be bad grounding in the car. some think it's your battery being weak, and when you're in WOT, the alternator switches off, so if your battery is old, the voltage might dip too low during WOT... still, others think it's a bad connection at the plug.

 

i want to test the battery theory. can you please log battery voltage, and do a WOT run so we can see what the V is when you drop connection?

 

thank you. hope we can get somewhere with this.

If the AP won't log, how would I do that? Never used romraider...

http://legacygt.com/forums/showthread.php/using-ebay-vag-com-cable-datalog-96737.html

 

...its a sticky at the top of this forum

No, the point is for him to log the battery voltage and have been logging it immediately prior to the connection dropping.

I like how the dickhead is laughing, when he didn't read the whole post... Thanks invar

Subscribed. Same crap has been happening to me.

Last May when I went stage 2 with Infamous , my AP worked flawlessly. The Cobb was sitting on my dash everytime I drove the car...no problems during 3rd gear pulls....plus I used the live data function to routinely monitor engine boost.

 

Then came the day I had to leave my car in a manhattan parking garage. I disconnected the AP---but left the OBII port in place.

When the garage attendant returned my car, he came out of the car holding the dongle, hanging from the USB cable ( like it was a dead mouse ). As he exited my car his foot had ripped the dongle out of the port !

Connection to the ecu keeps dropping ever since. I brought the car to Subaru...explained it all to the mechanic....he tested the OBII port ....found no problems . I even went so far as to send the whole unit back to Cobb for testing....they couldn't find anything wrong with it.

Now when I need to use the AP , I string the USB cable up from the dongle , between the drivers door and the dashboard to create a constant tightness or "pull" on the dongle connection. It works.

My battery is brand new ( 6 months old ) so I have to assume its a tiny connection gone loose in the port connection that won't show up when the car is sitting in the shop----just when it's moving.

PS....I did ask the mechanic how much it would cost to replace just the OBII port....he told me to forget about it. Apparently the port is part of a main harness that costs upward of $1500.00

 

 

Edit: And bmx is NOT a dickhead. He's actually a really helpful member of the forum. Let's keep things in perspective here.

I tried running the AP cable through the dashboard and kick panel by the drivers door, in order to make a "tight" connection and this didn't work. I guess the next thing to do is to check my battery, which is an optima...

Subscribed.

BMX--like most of the helpful/knowledgeable folks here--is in fact a dickhead. Increasing knowledge of these cars tends to increase how far the dickhead-o-meter can swing. Mine goes to 'medium' .

 

I stand corrected :lol:

Still trouble...any ideas anyone?

What parameters are you logging?

Does it only cut during a WOT pull or even normal driving around?

I'm logging engine speed, calc load, dyn. Adv. Mult. , ignition adv. , feedback knock correction, knock learn knock correction, knock sum, throttle position, boost, wastegate duty, mass airflow, mag voltage, af learning a-d.

 

I tried logging multiple times in third gear from 2k to redline. I tried changing cables from the obd connection to the AP to no avail. Tried pulling cable tight to ensure a good connection, and it still gave me the "trouble communicating with ecu". This only happens when doing WOT run. I'm trying to datalog in order for shamr to revise my infamous basemap.

 

Input appreciated... Btw the Battery is about thirty months old, and is an optima redtop.

 

 

Thanks in advance!

log battery voltage

Try logging just one parameter. Also, see if anyone near you has a Tactrix cable you can barrow too see if you can log with that.

 

I was able to get at least 1-2 full pulls after replacing my battery, replacing grounds, adding more grounds, and adding a .01μF ceramic capacitor between pins 5 and 7 on the OBDII port wires.

 

Ultimately, I replaced my ECU with one a used one I found for cheap. That fixed all my tuning/logging/weird rising RPM issues I had.

I had this issue at the track. I cut down the sensors i monitor and it worked.

I've experienced this problem before. For me, using a USB cable with a ferrite core did the trick and allowed me to be able to log again.

First, what version of the AccessPORT do you have? It is on up to date firmware? The early V2 uses a USB cable and a Dongle to connect to the car while the second version uses a 9 pin connector on the AP and a black OBDII cable. If you have the earlier version, try the ferrite bead on the cable to eliminate voltage fluctuations. If you've tried that and/or a new USB cable with no luck, we might need to update your AP internals to the V2b style. Give us a call or email me for details about that.

 

Ian

ian@cobbtuning.com

log battery voltage

 

Sorry to threadjack - what would normal battery voltage be? I just got RR to work, although I can only see "live" values, haven't figured how to log/graph yet. My voltage is 14.0, dipping to 12.8 briefly when I turn on A/C. Possible bad alternator? (this is all at idle)