Well that explains that.

[trippyjoey]

My dad owns a 95 GMC Yukon 2 door 4x4, just like the one I drive and em tuning but he bought his new from the showroom floor and got a rebuilt 350 two years ago but since only my brother drove it it has probably less than 30k miles on it. It always seemed to pull harder in 1st gear than my yukon even after I tuned but I could still beat him and outrun him on the short run and long run. Well I finally bothered datalogging his Yukon and found out that His knock sensor is not working so the ecm is not pulling any timing whatsoever and his temp is not rising about 60*C meaning that his thermostat is stuck open or missing.

[steveo]

you might find that at only 60c the knock sensor isnt even enabled in that calibration yet; so do the thermostat first...

many calibrations disable knock detection when cold, because valvetrains n bearings take a little while to shut up, and a dead cold engine usually doesn't ping with a stock timing table much..

[trippyjoey]

Well was thinking knock sensore too cause it gives an error code and a constant 115 value

[steveo]

ah.

could just be a broken wire, seems any time im reinstalling an engine or doing anything in that area i manage to knick or catch that tiny knock sensor wire on something.

[buddrow]

A constant value of 115? may have the knock sensor wire shorted to voltage. Should be pulling timing if thats the case.

Buddrow

[trippyjoey]

he knock counts stay at 115 and no it didn't show any knock retard