Block heater OBDII compatible?

[themaxx]

Hello all,

I'm looking for an engine block heater for a 2006 Chevy Colorado, 2.8 engine.

I'm finding block heaters with a " thermostatically controlled cord required for compatibility with the OBDII systems in these vehicles".

Why would there be a compatibility issue with an engine block heater?

I'm told the thermostat in the cord won't turn on the block heater until the temp hits 0 degrees F, I'd rather have it heating before that. Not seeing why I couldn't cut the thermostat plug off the end of the cord and put on a normal plug.

Any ideas? I feel like I'm missing something here.

 

[demarpaint]

I'd scrap that idea and use an oil pan heater. It will aid in cold weather starting much better than a block heater and there is no chance of a coolant leak. If you're looking to warm up the cabin faster then I would consider a basic block heater, which should have nothing to do with OBD-II if memory serves me correctly.

 

[kschachn]

I saw this once before, apparently the ECU can determine the coolant temperature is too high on start (or the rate of climb) and set a code thinking the sensor is faulty.

 

[demarpaint]

Originally Posted by kschachn
I saw this once before, apparently the ECU can determine the coolant temperature is too high on start (or the rate of climb) and set a code thinking the sensor is faulty.

That makes sense, and makes for a better case for the oil pan heater. I must be lucky, I have block heaters on three vehicles, and oil pan warmers on two of the three. I haven't had any CELs using them.

 

[racin4ds]

Makes me so glad I don't live where I'll ever need block heaters and oil pan heaters again! My F350 and tractors always were hard to start at 0*F or lower even with block heaters.

Now I complain during the rare few winter days that we see ~28-30*F! LOL!

 

[Pelican]

Why add so much complexity? The less one involves the ECU the better!
Nothing wrong with the "old" style Block heather and a timer IMO.

 

[Lapham3]

I have a 2006 Malibu with the 3900 engine that came from the factory with the thermo controlled block heater. I simply cut out the thermo and soldered the wires together and then shrink wrap and done with no codes or other issues over the years. I've used block heaters in many cars over many years and find them a very good addition.

 

[WobblyElvis]

My cousin had a 1990's? Pontiac Gran Prix with a small V6. I believe it was a 2.8. It came from the factory with a block heater but if it was used, the car had problems starting and would not run correctly for a few minutes. I think the block heater was to close to the temp sensor and the computer would think the engine was much warmer that it actually was. Perhaps this is the reason for the temp cut off switch in the modern block heater cord.

 

[bullwinkle]

Oil pan heaters are good, they improve crank speed due to warmer oil, & will warm the block somewhat, I can't imagine a pan heater getting a (usually) top mounted temp sensor too warm.

 

[demarpaint]

Originally Posted by bullwinkle
Oil pan heaters are good, they improve crank speed due to warmer oil, & will warm the block somewhat, I can't imagine a pan heater getting a (usually) top mounted temp sensor too warm.

I've used both the pan heater and the block heater at the same time and had no CEL issues. It is easy enough to plug both into a timer and set it to go on a few hours before driving if desired.

 

[ragtoplvr]

The emissions requirements require self diagnosis. Since temp is so important to emissions, they test it compare ambient to block after so many hours.

Rod

 

[themaxx]

Thanks everyone for lots of good info I didn't have and ideas I had not thought of.

It's much appreciated!

 

[HoosierJeeper]

My Liberty has an plain engine block heater, I've only gotten the code when it's been very cold (-40F) and it's been plugged in for 12 hours, guess that was enough of a difference to trigger the code.