hesitation, bucking???

[horrorbiz]

what up guys, newbie here

has anyone had problems with bucking in 1st and 2nd and hesitation in 3rd? i just replaced all 4 fuel injectors, fuel filter, had a tune up done, and checked rotor and disrtibutor cap. any ideas?

[JNM240]

coolant temp sensor? its very often overlooked.

[1991240xs]

yep..coolant system..my thermostat was stuck wide open and wouldn't let the engine get up to heat...buy a new thermostat...worst case you're out like 7.99$

[JNM240]

But if its the sensor, the ECU will never know that the car has warmed up and will still dump loads of fuel into it like it were cold, creating an EXTREMELY rich situation, which will be a huge loss of power and loads of hesitation. Been there, done that. Thermostat is a good idea to check, but if its stuck open, then it would just take a little while longer for the car to warm up. Once warm, it will be OK. Still a good idea to check and change if needed.

[horrorbiz]

ran the AC today and the car ran fine. turned it off and started hesitating again. does this narrow it down to the coolant temp sensor or do i need to adjust the idle again?

[JNM240]

Ya, check your timing. Also your idle speed. Is it too low w/o the AC on? When the AC compressor kicks on the engine usually goes a couple hundred RPMs higher.

[technoman]

Try cleaning all your connectors on each sensor. Contact cleaner works great.