Maybe you guys can help me out with this stumble problem. A few weeks back my water pump began to leak and I didn't have time to change it for about two weeks so coolant was dripping on my opti for two weeks. It ran fine those two weeks. Well that next week we changed the water pump, no leaks, no problem. Only problem I had was the car was running really hot close to the 3/4 mark. Well a couple days after finishing the water pump, I am driving to class and I am getting on the on highway and I punch it the car stumbles, I hear a pinging sound and a backfire from the motor. I am leaning toward the opti, but what is really weird about this story is that every since the stumble problem, my coolant temps have been around 170 and 180 and it has never been that low it has the stock thermo too. Also I removed the AIR pump while we were changing the water pump. Plugs and wires are about a year old. O2s are fairly new too. It is the original opti and I have a good 150,000 on the car which is another reason I am leaning toward the opti. What do you guys think? Any help would be great

 

Might be the opti. My opti did that but it didnt get wet. It would be fine one day and another it would act like shiat. Might want to check it for any codes that it might throw.

 

TTT anyone else?