so my truck blew a water pump last week, i fixed it and repalced the thermostat. works great.then i got an engine code P0051, turned out to be an 02 sensor, i replaced that today. the engine light went off for that, and also it did not help the truck. it still shakes at a certain rpm. and still sputters like its missing. the o2 sensor was supose to fix this problem and didnt. now on the way home the code P0301 came up...i believe this cylender 1 misfire. what do i do and why is my truck sputtering/missing. it also shake at about 1600 rpm and 47mph. major loss in performance. what do i do? please help. all help greatly appreciated.

 

ahve you checked plugs/points/gaps/spark?

 

no not yet. how can i check them other than putting new spark plugs in?

 

also the rpms go up and down a little bit when driving. no more than 100 rpms..but you can see the needle move a little bit when i know im not moving the gas pedal. the rpms just go up and down by itself

 

When you changed the o2 sensor did you reset the computer?

 

Disconnect the battery and go make and eat lunch. When you're finished go back out and reconnect the battery. See it you still have the problem.

 

usually when you get a cylinder misfire code, its a bad coil pack, wire or plug

 

also, check your catalitic converter...I've seen those things clog up and cause wierd problems

 

ok. i have reset the computer. let it sit for like 20 minutes and then reconected it. and it cleared the o2 sensor code. i guess its probally the coils/plugs/wires. how would i know wtihout changing them? and how do i know if my cats are bad. it just seems weird to me that this all of a sudden happened and wasnt a progressing problem.

 

If you have good flow through the tail pipe the cat is good