Extremely high MAF reading during pull

[Squib308]

Wondering if anyone knows or has a theory on why BTSSM would suddenly report a 500+ g/s MAF reading during a pull.

 

The attached log (short) demonstrates what I am talking about. I assure you, that my setup is not capable of pulling 500+ g/s. :/

 

Yesterday I did a pull & I saw the 500+ g/s MAF, and 128 misfires on cyl 3 (but I was only monitoring cyl 1 and 3). No misfires on cyl 1. Unfortunately, I wasn't logging then.

 

The only change that has happened recently is that I added a custom 'knock sum' field to BTSSM.

 

Is this something I should be concerned with, if so, are there other parameters I should be looking at to help diagnose what's going on?

 

Thanks in advance, B

BtSsm_20180815_115637.csv.odd maf value.csv

[solidxsnake]

Looks like a read error in BtSsm, not a real reading from the ECU. Notice that the MAF voltage is the same in the cell prior (4.16V), which means your MAF should be nearly the same as the previous cells with a MAF V of 4.16V (would be more precise but the built-in BtSsm fields round away any more precision than 2 decimal places).

 

 

I'd just throw-away data that looks very obviously wrong. It's possible adding extra parameters is causing BtSsm to not handle collecting the data properly from the ECU. What are you connecting to the ECU with; a BT dongle, Tactrix cable?

[Squib308]

Looks like a read error in BtSsm, not a real reading from the ECU. Notice that the MAF voltage is the same in the cell prior (4.16V), which means your MAF should be nearly the same as the previous cells with a MAF V of 4.16V (would be more precise but the built-in BtSsm fields round away any more precision than 2 decimal places).

 

 

I'd just throw-away data that looks very obviously wrong. It's possible adding extra parameters is causing BtSsm to not handle collecting the data properly from the ECU. What are you connecting to the ECU with; a BT dongle, Tactrix cable?

 

I did notice the MAF voltage was similar to the previous cells, that's why I was logging that.

 

I'm connecting to the ECU with a generic Tactrix-like cable, to a samsung galaxy 6 phone.

 

I've never seen this happen before, so I'm wondering if it's in some way related to adding the custom knock sum field. That would be strange, but strange things happen.

 

I guess I'll try a few things - remove the misfire fields, so it updates the rest of the fields more quickly; try disabling the new knock sum field I made; do some pulls, drive around, see what happens.

 

Thanks for the response! I appreciate it.

[solidxsnake]

I've never seen this happen before, so I'm wondering if it's in some way related to adding the custom knock sum field. That would be strange, but strange things happen.

 

 

That wouldn't be strange if it's unable to capture all the data you're requesting in the given time it (the ECU) has. Adding another request is likely what caused it.