Nothing! The engine runs wonderfully! I've never had a problem... and I must admit, I was worried when I first bought the car. It was used and had a lot of miles on it, but my Geo is VERY reliable!
The only "problems" (they're so small... I would hardly call them problems!) are:
My interior dome light burnt out and Advanced Auto parts doesn't carry the bulb, so I have to get into a dark vehicle at night. I thought about going to a dealer to get a replacement bulb, but I haven't got around it it yet.
Also, and this doesn't happen on any kind of regular basis, my power steering goes out for, like, a second when I turn slowly into parking spaces. I had the belt checked (my brother's Mercury Sable had problems with its power steering and it sounded like what my Geo does, but it doesn't happen frequently). What happens is, when I'm turning slowly into a parking space (and only a parking space, never around a bend or at a stop sign... it's very random), the battery light comes on, my headlights dim, and the wheel becomes very hard to turn. I thought my battery was bad, so I replaced that around 85000 miles, but it still does it every once in awhile. Who knows!
That's it. I call this car "the Warrior."
I was hit from behind in December of 2003 and I was sure that I was going to get out and see the back end of my car in the back seat (I was hit by a minivan going 35 mph and I was only going about 5 mph). However! On the outside, it didn't look like anything even happened! (aside from my license plate being in pieces on the other side of the road). It turned out the frame was damaged and my trunk doesn't close on the first try anymore, but that Geo held up! It's the Warrior!
I live in a rural area, so when it snows, it SNOWS! and the roads don't get taken care of. My Geo is great in the snow! Granted, I can't be speeding and taking sharp turning, but he climbs snowy hills well and gets me to work when the inches pile up.
I drive this car hard and it is always up for the challenge! He can't climb hills very well, but you give him a flat highway, and he can get up to 106 smoothly (I have the points on my license to prove it!) :) I love my Geo. I always say the only thing that is going to stop him is impact with a Mac Truck.
Hi, it sounds like your main fan belt is slipping, have it changed and you should solve your headaches.
Well my 1990 Geo Prizm WAS hit by a truck! An 18 wheel Freight Liner. (On the highway!) Although the entire drivers side of the vehicle was wiped out. I was still able to drive myself to the hospital!
I can't believe that the front end wasn't even knocked out of line!
My 1995 Geo Prizm was also rear ended by an Oldsmobile going at least 25-30 MPH; No Damage. Damn these cars are solid.
I smashed my '96 prizm into a deer at 50 mph. A new hood, left head lamp assy. and a minor dent. The vehicle is still mechanically sound and I will continue to drive it till it dies. This vehicle also has 180k miles on it and starts like a champ in the coldest of WI winters. I have gotten it stuck in the snow once since 1996 and that's because my ally was never (ever) plowed and it happened to be a blizzered out. The snow was higher than the front spoiler.
If the belt is new or in good condition, you might want to check the tensioner. Not being able to steer can lead to embarrassing driving situations!
Another distinct possiblity is that the power steering system is clogged or low on fluid.
You might want to try tightening the belts. I had the same problem with my 96 prizm and it fixed it right away.
Replace or tighten the belts, if they slip, your power steering pump won't turn, nor will your alternator (hence the battery light coming on) Fyi, there are no spring loaded tensioners, just bolts with lock nuts. I am a toyota mechanic and have wrecked, whooped, and beat this car physically, but have religiously maintained it. Runs AWESOME 190k on it now. Just maintain the powertrain! I'd buy all the 96 and 97 prisms (1.8l) I could find if I had the extra parking!