Ok, here's my situation; 1998 f150, 2wd extcab, 4.6, 142000 mi., I changed the sparkplugs twice in 6 months last weekend was the latest. Thanks again for the forum it's been extreemly helpful with tips. Ok, on with the problems; check engine light on, take it to friends house w/code reader, code states (egr valve) first trip. I replaced egr, light comes back on. Second trip back to friends house now the code says (misfire #5) 02 sensor and something else neither of use could find in his manual, I believe it was CTK bank or CKT bank. Anyhow, I replaced the upstream 02 sensor and still nothing changed. So now last weekend i checked the plug wires, which i replaced when i changed the plugs the first time (six months ago) they seem ok, I cleaned the TB with the "seafoam" cleaner, which seemed to help initially, but now the engine is running even worse. It runs ok at startup, but as soon as it's put in gear it gets the shakes very bad. Once out on the road it is ok until I come to a hill and then it gets the violent shakes and the check engine light starts flashing. I really don't want to go to the dealer with it, I had an unpleasent dealing with them the last time around. Is there anything else i can replace myself or clean? Please help, I'm pulling my hair out and don't have that much left anyway. Thanks

 

Hi and welcome to the forum

Don't go replacing a bunch more parts until you get the P0305 code fixed.
What brand of plugs did you use?
Does the engine use any oil or coolant?
Ever had the injectors flushed?

 

Autolite platinum, Yes injectors flushed about a year ago, and no coolant loss. As far as oil it uses about a quart every 3000 miles.

 

Post the exact codes.

There are no codes that tell you what part to replace, they only tell you that the computer has a problem with the condition or operation of a given sensor reading or actuator. You can waste a LOT of time and money replacing parts based on codes only if you don't bother to follow the diagnostic routine in the service manual.

Post the EXACT codes (Pxxxx where xxx is a 4 digit number). Many codes have been discussed before and many are common ones. Use the SEARCH feature and enter the code # as the SEARCH argument to find previous threads about it.

Steve

 

I have a 97' that from the sound of it, is doing the same thing. Truck has been great up till yesterday morning. I am about to start troubleshooting this morning. Any suggestions on where to start?

 

Never mind... I figured my problem out. I down loaded the codes, P0303 (#3 mis-fire). I recently changed the plugs, but not the wires. The lead to #3 was shot... put a new one on and good to go. always nice to find a quick fix!!!