Thread: help have engine knock.

Well guys got everything back on after switching injectors and still getting a misfire on #3 come up with SES light just flashing on and off.. I'm at loss on what to do guys... any more advice and I'll try something else. Thnx in advance..

Sorry Scotty posted that up right after shower and right before bed. Was out tinkering with this thing about 3 hours after getting home from work and still haven't a clue as to what could be wrong..
Anyways here's what all I've done....

1.First after iniatially hearing a mysterious knock turned out to be a loose rocker..
1a. Removed valve cover and sure enough rocker on #3 was loose. retorqued it and knock eliminated..

2. Noticed miss in car after tightening rocker. Went to get scanned. Got a 0303. Checked wires and plugs. Found a bad plug.
2a. Replaced all plugs with OE iridiums..

3. Still noticed a miss so went ahead and bought a scanner and scanned. Got a Po303-Powertrain Cylinder 3 misfire..
3a. Swapped wires around again and no change.
3b. Replaced wires and no change.
3c. Swapped coil packs and no change.
3d. Bought new coil pack to be certain and no change. Used electrical grease on connections eventhough no corrosion was noticeable.


4. Rescanned and still getting a p0303-Powertrain Cylinder #3 misfire.
4a. Removed valve cover and rechecked rocker to check torque spec at 11lbs. Rechechecked spring. All looked good.
4b. Swapped fuel injectors in #1 and #3 to see if maybe bad injector. While doing this I noticed fluid on top of manifold with what seemed like a bit of antifreeze but not alot. Cleaned it up and cleaned injectors. Checked O rings. Good.
4c. Put everything back together. Checked for leaks and anything I could of left loose or broke and all looked good. Hooked up battery and turned on ignition (without starting car) to pressurize fuel lines and rechecked for leaks. All looked good.
4d. Checked oil level. Checked coolant . And fired her up. And absolutely no change. As if I hadn't even touched it. Rescanned and still a po303-Powertrain Cylinder 3 misfire..

HELP!!!

Nighthwk I was thinkin the same. After looking at everything Im thinking its gotta be the lifter or a chipped piston. That's really the only thing I haven't looked at. And yea I've cleared the code after everything I 've done or replaced.. Thnx for reply. I'm really just debating if I wanna sink more money in this car or not. But I guess I need to just take all of it off and check to make sure. I got this car for 4K almost 5 years ago and its been pretty good for the most part. But all this little stuff popping up here and there are starting to add up.. Not sure if it's worth dumping more money into.

Originally Posted by twentyocho

Nighthwk I was thinkin the same. After looking at everything Im thinking its gotta be the lifter or a chipped piston. That's really the only thing I haven't looked at. And yea I've cleared the code after everything I 've done or replaced.. Thnx for reply. I'm really just debating if I wanna sink more money in this car or not. But I guess I need to just take all of it off and check to make sure. I got this car for 4K almost 5 years ago and its been pretty good for the most part. But all this little stuff popping up here and there are starting to add up.. Not sure if it's worth dumping more money into.

Well, why not, right? New valve train means modded rockers, lifters, retainers, valves, springs, and and cam! Yay! Might as well do the timing chain while you're in there. New piston means lots of work, though, so you might as well make that worth the time - forged pistons! H-rods! Heads! Rawr!!!

You could just get away with replacing the valvetrain (or entire head), lifters and do the LIM gaskets while you're there and be good to go assuming the pistons are good. No need to replace the chain as they rarely have an issue. Being his work car I doubt there is a huge need for a forged bottom end (with another $400 for machine shop) and all that. Methinks his wife would probably put the kabosh on that idea real quick anyway, lol..