2001 Pontiac Sunfire


Just purchased this used vehicle a short time ago. Very good shape body wise but the engine has started to act a little strange. Periodically, during acceleration from a stop the engine will not go past 12 mph and occasionally stalls. Seems to happen when it is VERY WARM out ( over 85 )

Anyone know what might be the trouble.


4 cylinder, I presume? Does the engine cough or backfire when it lugs? Have you replaced the fuel filter? High under-hood temperature can cause stress on plug wires and coils as well as ignition modules. Has the check engine light come on? How many miles on the car?




Sorry, wrong click. 4 Cyl. No backfire or odd noises. No check engine light. No excessive heat indication from gauge. Have apt to change gas filter today as it was the cheaper option to try at this point. No one seems to have an idea so any suggestions would be appreciated.


Check engine temp sensor. (not the coolant temp sensor)


Thanks for your advice. Have so far changed the temp sensor and also throttle sensor. Will see what happens after a few days of test driving. As it did not happen all the time, a remedy is hard to determine.


Well have changed both the temp sensors and the other one mentioned but this thing continues to sputter on very warm days. No one seems to be able to diagnose the trouble. Looking for any avenue to persue here to remedy this annoying problem… THANKS!