: OBD2 Scantool for Northstar Engine to monitor knock?

09-22-08, 03:34 PM
Hi all, newbie here. Iíve got a 2005 Pontiac Bonneville with the 275-horse NorthStar engine. Iíd like to know if anyone here is aware of any OBD-2 scanner is capable of monitoring spark retard due to knock for a Northstar PCM. If spark retard is not available, total advance might be an acceptable substitute. Iím open to any experience or feedback regarding the different scantools; I want to be able to datalog and measure performance as well.


09-22-08, 03:38 PM
Take a look at www.scangauge.com. You can monitor any 4 of 12 gauges at one time, and ignition advance, throttle position, coolant temp and intake air temp are 4 of them.......plus it's a code reader/scan tool. Plugs into the OBD-II port with a 6-foot cable.

I can tell you from experience that the ScanGauge ignition advance/retard function zips all over the place depending on any little change in any little engine operation. It would be practically impossible to factor out the actual retard under various loads with various fuel mixtures.

09-22-08, 05:46 PM
Also look at the BR-3 model at http://obddiagnostics.com/index.html

I have been using one for years and the PCM information available (and logable) is worth the price. Download the s/w and take a look at the parameters you can monitor. Laptop required.

Indeed, spark timing is a continuously moving target. You have to log several parameters to get a feel for why the PCM altered spark timing at any given moment.

BTW, that is a rare vehicle you have. Please do take care of it and when you decide it needs a new home, send me a PM.

09-22-08, 07:31 PM
Thanks for the replies. I haven't messed with the OBD2 stuff, but I was hoping that there would be a way to display the retard due to spark knock. I'd expect this to typically be zero, unless knock was detected and the PCM was pulling timing. I know that the GM 3800 guys are able to monitor this through 2003, and when they see retard due to knock, they drop the boost, update the tune, put in better gas, or whatever to address the issue.

I'm planning on attemping to tune the car using a MAF translator, but I really do need to know if the engine is seeing any knock. If so, it will mean I've gotten too agressive and need to richen up the AFR.

09-23-08, 11:47 PM
Check out also Carplugs for Obd2 USB CAN scan tool.

I've been using their USB version of the obdii scanner and it works great.