Logs Jumping

[The1]

Hi All i get some logs from people jumping like in this log between 6.57 - 7.02, the data looks to be there but just skips that spot, any ideas? Log is for VS V6

[Holden202T]

its not the download bin feature is it ? i know when im logging and hit the download bin the log pauses while it downloads.

[The1]

laptops sitting on the seat in the car while driving so not downloading or uploading cals.

[antus]

The data isnt there, probably electrical noise on the ALDL bus. I saw this on a methanol sprint car I was tuning on the dyno. It'd misfire at a certain RPM and the misfire created such electrical noise for a couple of seconds the log looked exactly like that. You dont see the corruption because the checksums fail and the data is dropped, and TP just stiches the nearest points together so you get a straight line. You can see there is no data there because on the monitor page you cant select any data frame in that range, it just snaps to one end or the other which are the nearest samples. Missfiring is just an example, it could be something else.

[The1]

makes sense, thanks

[Holden202T]

it could be solar flares ??

[The1]

there's a few of those happening in the combustion chamber.

[trikky73]

hmmm think I have seen that log somewhere before oh wait it's my log

looks like I have an poor connection somewhere as it tends to do this when goign over a bump etc. does not effect the car at all some gaps in the data can go for 10secs

i have checked the earth and connections on the ALDL socket as well as running new earths fromt he battery to engine, ECU etc. with no change

have tried 2 different ALDL cables with same result, strangest thing is that data is stable in efi live?

The1 suggested it maybe the BCM creating excessive chatter but have not got my hands on one to try yet but I am leaning towards a poor connection somewhere since it is effected by bumps

[VL400]

Hmm, with it being stable in EFILive then it could still be a couple of things - either you do have a connection problem somewhere or its a TP software issue.

This may just require some ADX configuration, but TP does not use the checksum in each data frame. Awhile back I tested this on the logger firmware by stuffing the checksum of every frame, TP was still happy to connect and show the data (all data was valid just the checksum was not correct). EFILive does use the checksum so a single frame that loses some info will show up on the screen log as a checksum error - do you get these at all? Where as TP will still try and process it but being a short frame will most likely be all out of wack for a little bit until the data timeout and buffer flush occurs - there really needs to be a debug mode in TP to see exactly what is happening though

[The1]

yeh it is your log, but im also having another car with the same issue, yet to fix it