Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 1998 Pontiac Sunfire owners, lightly cleaned up (personal details are redacted by NHTSA).
In my 98 Sunfire gt I have some major problems with yet I still own the car. A little bit ago it seems like my exhaust pipe falls off from the exhaust manifold from the flange. With causing your car to sound like it was a drag racer. Well I went to Pontiac and figured out that it was going to cost me a pretty penny $500 some odd dollars. And the funny thing is that this has not just happened to me. It has happened to a few of my friends as well. I don't how know many times you have gotten letters about the faulty exhaust flanges.
The temperature guage flutters from time to time. Then it will go all the way down to 0.when it starts to flutter again the engine seems to be racing. The tach. Guage will bounce about 200-300 prm. I also noticed that when the car is in park and you idle the engine up to about 3000 RPM, it acts like there is a rev limiter. It has never done that untill a few months ago. The check engin light has never come on until today. I changed plugs and plug wires and it didnt help at all.
Coolant had been leaking for over 3 months off and on. Put in stop leak for a temp fix. However dexcool continued to eat away at my coolant system. Car has overheated on many occasions. Finally able to use jb weld to fix leak .
Consumer was having problems with the EGR valve. Dealer notified. While driving the EGR valve became stuck in the open position which caused the engine to rough or stall without warning.
First this clicking/popping sound started coming from the steering wheel when you turn it at low speed. The mechanic said its the inner tie rods that need to be replaced. But to replace them you have to replace the whole steering assembly because there made as one piece. Then one month ago the car started shacking at idle speed. If you are in drive or nuetruel at a stop light standing still you could feel it shacking a little. The dealer said it could be anything from electric problems to coil problems. But just yesterday I was driving at night on the freeway going about 60mph when I saw smoke behind my car. I got on the shoulder and saw smoke comming out of the engine. Then I tried starting the car but it won't start. So I had it towed to my house. At my house I checked the engine with a flashlight and found a big hole (3-4 in diameter) in the engine by the dipstick. …
I've been having multiple problems with my 1998 Pontiac Sunfire gt. Last month I had a fuel injector and water hose go bad and need replaced. The suction hose pump for the ac was leaking and had to be replaced within the past 3 weeks. In the same time period, the compressor started leaking. I've had 2 different compressors put in, and both have leaked still. The 3rd compressor is being installed today, so we'll see whether it leaks too. A compressor should really last longer than 5 years, and I shouldn't have 3 compressors in a week trying to find one that doesn't leak. There's also a crack in the welding that needs to be fixed or it will start leaking. One of the fan parts went bad, so now level 1 on the fan adjustment doesn't work. This seems like alot of problems in a short timeframe, especially with 3 problems being for the air conditioning. …
I think you have a problem when you have a 2 year old car seems to be falling apart from the inside out. I originally owned my car for 3 months when the temp. Gauge zeroed out from a shorted out fuse. The next problem was odometer went blank and showed me symbols in 05/1999, and the electrical cluster was replaced. Later in 09/1999, my coolant system busted after a visit to the dealership, where I was told that cars are okay to reach the red line before it will overheat. Most of the coolant system was replaced and tests done. I did not trust the work, and took it to another GMC dealer, to find that the coolant temp. Sensor needed replaced, just 2 days later. Now in 08/2000, my odometer is showing the same old symbols, due to an electrical problem. My problem is electrical problems are right in front of me, and I am unaware of it. …
Problem with car stalling, hesitating, and idling rougly. Started about a year ago. Was having this problem and received technical bulletin # 00032. Took car in. One spark plug wire was replaced. A month later same problem. Another spark plug wire was replaced. Now, about eight months later...same problem except seems to be more extreme. Replaced all spark plug wires on my own, but still having problems. This has been an on going problem for over a year and the dealership still has not been able to fix the problem. Have become very disgusted with the dealership and no longer want to take my car there. This also seems very dangerous to me because I never know when my car might stall or hesistate. Please give me some information on how I can fix this problem. Obviously, this is in other cars to or they would not have sent out the technical bulletin. …
Problem with car stalling, hesitating, and idling rougly. Started about a year ago. Was having this problem and received technical bulletin # 00032. Took car in. One spark plug wire was replaced. A month later same problem. Another spark plug wire was replaced. Now, about eight months later...same problem except seems to be more extreme. Replaced all spark plug wires on my own, but still having problems. This has been an on going problem for over a year and the dealership still has not been able to fix the problem. Have become very disgusted with the dealership and no longer want to take my car there. This also seems very dangerous to me because I never know when my car might stall or hesistate. Please give me some information on how I can fix this problem. Obviously, this is in other cars to or they would not have sent out the technical bulletin. …
Problem with car stalling, hesitating, and idling rougly. Started about a year ago. Was having this problem and received technical bulletin # 00032. Took car in. One spark plug wire was replaced. A month later same problem. Another spark plug wire was replaced. Now, about eight months later...same problem except seems to be more extreme. Replaced all spark plug wires on my own, but still having problems. This has been an on going problem for over a year and the dealership still has not been able to fix the problem. Have become very disgusted with the dealership and no longer want to take my car there. Please give me some information on how I can fix this problem. Obviously, this is in other cars to or they would not have sent out the technical bulletin. And plus, I read many complaints of the same problems on your complaint page. Any assistance will be well appreciated. …
Engine complaints in other Sunfire years
Frequently asked questions
How common are engine problems on the 1998 Pontiac Sunfire?
NHTSA has 32 complaints about the engine & cooling of the 1998 Pontiac Sunfire, 27% of the model year's 120 complaints. The component named most often is engine › gasoline (18 mentions).
Is there a recall for 1998 Pontiac Sunfire engine problems?
No. NHTSA lists no engine & cooling recall for the 1998 Pontiac Sunfire, though it has 3 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 1998 Pontiac Sunfire engine problems start?
Half of the complaints with a recorded mileage happened before about 52,000 miles, and 20% before 25,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.