I am looking possibly at a 2000 blazer that has a few issues. It seems the truck is in limp home mode that restricts it to first and second gear. The only error code recorded is low voltage on the throttle position sensor which the guy is saying wouldn't cause that problem (are these expensive to replace?) . He's been told its likely to either be a fault on the MAF sensor circuit (is this common?) or a problem with the gearbox solenoid for third and fourth gear. Is this a common fault with the auto boxes? Could it just be a broken/loose wire or is it likely to mean a gearbox rebuild?
It would need to be pretty cheap for me to buy it with these issues, its done 112K miles

http://cgi.ebay.co.uk/ws/eBayISAPI.d...E:B:SS:GB:1123

 

I just turned around and came home because my s10 blazer is doing the same thing it has done this before and the vehicle speed sencor is what makes it do this . How is your speedometer working? Its located on the tail shaft of your transmission or transfer case if you have 4x4 . The part number for it at advance autoparts is S8310 .

 

Among other things that can cause the problem is an issue with the transmission 2-3 gear solenoid. I would pass on that truck until the owner fixes the problem.