hey guys, got a little problem with a 94 tbi chevy truck. everytime i drive it, about 5 minutes after the engine warms up the SES light comes on. since the truck is my dads(i'm driving it to college since my cars in the garage for a MAJOR oil leak.. but thats another issue), he installed a new thermostat a few months ago. the warmest the engine can get is about 125*.. i told him that is way to low, and that he should stick really close to where the stock recommendation is(180 i think). he said (in his shut-the-hell-up-i-know-what-i'm-doing voice hehe) 'dont worry about it, its a cold t-stat and it should run cool..' i said yea maby around 160(the coolest t-stat i've heard of) but definately not 125-130. i know his fans are rigged to come on at the stock temp(around 200 im guessing?) so im convinced the stat is stuck open. in any case, the SES light comes on a few minutes after it warms up as much as its going to, but mechanically everything seems fine. the engine has power, the tranny is shifting fine, tc is locking/unlocking fine.. nothing out of the ordinary. i dont want to pay someone 50 bucks to run a diagnostics check on it.. so i was looking around for a list of trouble codes but no luck(if i can do the ole paper clip trick).. any ideas? i really appreciate any help.. -josh