I have the stock thermostat and my car usually runs a little cooler than 220 on the highway, so about 200 degrees and 220 or slightler more in town at stops and such. My car is a 1993 SE. Should I get a 180 t stat and if I should does anyone have any instructions on how to change it?

Also I recently had some trouble when my car would really warm up or when it was warm outside, it would hesitate, couldnt increase speed or would just very slowly, it ran fine in cold weather. I replaced the MAT sensor and its running good now but its also cooler outside today. If that didnt fix it what else could it be?

Thanks

My car runs at the same temps as yours, and I notice a decline in performance when its 220. I'm getting my 180 put in this weekend. I reccommend you get one.

I would definately put in the 180 T-stat. My car had always run warm/hot and when it did I could tell my performance suffered. The best gain isn't performance but engine life. By going to the 180 you will help save the internals to your engine.

Here is something worth reading if you haven't already.

http://www.bonnevilleclub.com/techinfo/?article=52

This will be close for instructions but not quite the same. If anything I think yours will be easier.

http://www.gp-owners.com/upgrades/thermostat.html

I always get worried when my car gets hot like that. It'* just too much for that plastic.

So I just go to autozone and ask for 180 t stat for a 93 bonneville? Also, do I have to drain that 1/2 qt of fluid? and if so, where is the petcock and how do I operate it? And what kinda gasket sealer works best?

Red RTV Best **** out there

Welcome to the board Kuhl.
No offense to Kuhl, but we really need to encourage newbies read the technical section and use the search tool. The Tstat topic gets rehashed about every 6 days.

The problem with that is when you go into the tech info all it says is to change your tstat but it doesnt say how.
When you search the forum for the thermostat you get every post that has the word thermostat in it which includes signatures. So perhaps a new guide should be made specifically for the tstat and it would eliminate the 6 day thing.

Yep...

No Problem, I understand the frustration.
One thing to do if you haven't yet is pick up a Haynes manual (some prefer Chiltons) on the car. They run about $15 and they're a great investment, and will pay for themselves the first time you do something like a Tstat change yourself instead of paying someone $70 an hour. Those books will walk you through it with steps, pics and all. Then if you want to get more hardcore, buy the shop manual for your year of vehicle, off ebay or something like that.

We can walk you through a tstat change, where do you want us to start? (In other words, how much about your engine, or engines in general, do you know?)

I know more about intake, sensors, and electrical than I do about the engine but I still have a fairly good knowledge of it. I dont know a lot about my engine in general but I have heard it is an excellent engine that has been used for several years because of its reliability.

How do I use the radiator petcock? If I really tried to mess with it I'm sure I can figure it out fairly simply. If I do lose a bit of fluid I'm sure the full-service station up the road could hook me up. ah well I'll probably just buy one of those manuals when I get a little surplus money.

What do I ask for when I go to auto parts place? If I just ask for a tstat for a 93 bonneville they will probably try to sell me the 195.