how would i know if the head gasket is blown on a 2001 pontiac montana

the cloud of white smoke is not that bad. but just noticed the change of thickness today. do you think the radiator itself could be blocked or no good? it doesn't miss fire but i can fell the change n the drive when it starts to overheat. they quoted me at 100 for a block test. looking for a cheap solution just in case i have to do some major repairs like the h.gasket.

Sorry to say,it may not be worth investing anything in repairing this vehicle. The fact that the waterpump and Tstat were replaced tells me the vehicle overheated recently, and some quicky repairs were done to make it drivable. White smoke with a slightly sweet oily odor is sure sign the head gasket is blown. Yes you can replace the gasket but doing so without milling the head (which is surely warped from overheating) makes the entire project very costly, not worth it for a 13 year old vehicle, IMO. Sorry! If you got even a 30 day warranty, take it back asap, work out a trade with the seller, anything.

I just scrapped my 2001 Montana, bad head gasket, local shops wanted $1400, dealer almost 2K. Replaced water pump, thermostat, constant oil changes and radiator flushes still did nothing. Over 200K on it, only paid $500 when I bought it and had it about 1.5 years. I would go back to where I bought it from and raise hell, sorry to hear that.

Yes, the Montana's as a whole are Lemon's along with most of the 2000 and up models. The Powers that be should hold GM at fault for their complete disregard of craftsmanship and dignity. Selling total rip offs to tax payers, instead they forced you to bail out GM.