Ok, so I keep on getting the error codes P0135 and then also had code P0300 but the thing is the truck runs fine when it is cold. Then once it warms up to operating tempature it starts missing / sputtering and it is really bad unless you get on the gas and even then it will herk and jerk while you are driving it. Anyone have any ideas? For awhile it was burning up fuel pump relays but that problem has seemed to gone away, and the plugs have been replaced as well as the rotor and cap. I have no idea when the o2 sensors were replaced or if they ever have been but could that P0135, keeps on coming up, I clear it with the code reader and then it comes back a day so afterwards. If anyone has any ideas I am all open ears. Should I try replacing the plug wires or would it be something different, or you think it is a computer problem or the 02 sensors where should I go from here as far as diagnosing? And I dont think it would be a tranny problem? Any help would be great.

Also, my blazer is about too turn 200k do you think it might just be the O2 sensors? Especially with that P0135 code coming up all the time?


Thanks,
Joe

 

P0135 is an O2 sensor code. I believe that the engine will run in open loop mode until warm which would bypass the O2 sensors. Once the engine warms up then it starts taking readings from the O2's and if your's is malfunctioning then that would explain the sputtering only after it reaches operating temp. Try replacing the O2 sensor that's indicated by the code or it might be a good idea to replace all of them due to the mileage.

 

Here is the Freeze Data taken at the time the P0135 Code was Thrown last:

RPM: 1039
Load: 6.2%
MAP: 41 KPA

Coolant Temp: 107 F

Short Term Fuel Trim 1: 0.0%
Long Term Fuel Trim 1: -2.2%

Short Term Fuel Trim 3: 49.2%
Long Term Fuel Trim 3: 60.9%

Speed: 22 MPH
Fuel Sys 1: OPEN
Fuel Sys 2: N/A

Based on this info, I dunno if you guys would be able to give me anymore insight into the problem. Just figured I would throw it out there since I got the reader that gives me all the info.

Thanks Again,
Joe