1996 Saturn SL2

First of all thank u for ur donation it really helps to keep this site going so we can answer everyones questions. Wow u have a few problems let's work thru a couple and see which ones take care of others. Starting with ur starting concern that sounds like ur coolant temp sensor and that make ur car boil over in the summer. It's screwed into ur head below where the upper hose goes on it has two wires going to It a yellow one and a black one. If the connector is corroded u will have to replace the connector. Also make sure u get a brass tipped one the plastic tipped ones crack and cause all kinds of problems. Replacing that might solve three of ur problems the starting concern over heating and idle but get that changed and let's see what happens. Ok ur squeling belt sounds like a weak tenisor if u turn the a/c on does it squel more?Now ur dim lights make sure ur battery cables are clean and tight.U could have a bad alternator there. Is ur power steering working ok if it is then the dim lights probably aren't being caused be the belt tenisor. Do u have a multimeter?Now explain ur car is getting loud alot better so we can figure that out too. Also go to a auto parts store like autozone and get ur codes read an bring me back the numbers. Let me know what u find.

Ur code p0711 is transmission temperture performance it sets if the coolant verus the transmission temp is greater then 40 degrees differnce. Which Is ur bad coolant temp sensor make sure u check that connector for corrossion. Ur p0133 is ur front o2 sensor u said u changed that the one in the exhaust manifold. Are u sure the the p0404 isn't a p1404?Ur p0137 is ur rear o2 sensor low voltage the one by ur cat. With the code p0133 p0404 or p1404 and p0137 I would check ur ground under ur intake manifold it's a couple of tan wires with circle connectors with a small bolt holding it to the block. If u take the air intake tube off throttle body and remove it look down by the fuel lines under the intake with a flash light u will see the ground. The ground feeds all the 5 volt sensors like egr both o2 sensors the throttle postion sensor all that so check that out and let me know what u find. Get ur alternator tested also along with ur battery. Let me know what u find.

I would make sure u have the correct belt number put on ur car. As far as the belt I would make sure u get a new belt tenisor that's why ur belt was squeling before u changed the belt.U have a weak tenisor make sure u get a factory tensior or a a/c delco one I have tried all the other ones and u can hear them rattle when u excellerate. Did u ever change ur coolant temp sensor?And check to see if the connector to it was corroded?Let know.

Well if ur belt is really squeling the only thing I have seen cause that is one of the pulleys freezing up which doesn't sound like that's the case if the noise goes away when u rev it up. And also a weak tenisor it will eventually fail and leave u stranded because ur alternator and. Water pump will fail to turn. The tenisor makes the most sense if ur belt is slipping the only thing that keeps ur belt tight is the automatic belt tensior. Let me know what u find.