I just had Reinhart flush exhausts with the thundermax auto tune installed on my 2007 Deluxe. I noticed that the check engine light came on once my oil temperature reached 170. This never happened before with the stock Harley ECU and exhaust. The temperature did get to 170 before but the check engine light never came on. The performance shop told me that the stock Harley ECU was incapable of turning the check engine light on when the oil temperature reached that high. Does this sound correct, or is this guy trying to pull one over on me? He did reprogram the ThunderMax and now the temperature does not get above 240, and runs very strong. I just want to know if I can trust him for any future mods.

Thanks.

 

I meant 270 not 170.

 

He may well be right as more than a few guys on here have reportedseening 270 with no mention of the check engine light coming on with stock ECM's.

 

Thanks, I was hoping that he wasn't trying to scam me.

 

You can always check with Zippers, I'm sure they would knowexactly what their own ECM can and can't do compared to the stock unit.

 

According to the Tmax manual, it does not come on based on oil temperature but head temperature and then at 325 (the default setting) but it can be set to any number you want. Evidently 325 is consider dangerous and it says you should immediately stop. My oil temp never gets over 225, but I live in the NW and it does not get all that hot here.

 

I wonder if your oil temps are higher than you think, or the ET (engine temp) sensor is a little screwy and reading or sending out artifically higher readings than it should.

 

Will the stock Harley ECU also show a check engine light when the head temperature reaches a certain point?
Thanks again.