I posted earlier about a problem that developed after my dyno. I developed a bad miss, I also noticed a slight tapping sound under the hood. I pulled my valve covers, and pushrode. 6 or 7 you couldn't see thru, so I cleaned them with carb cleaner. When I put it back together with my fouled plugs, it seemed to run much better. was it possible my miss and lost power was caused by a lifter not pumping up? And now that the push rod is clear its pumping up good? It was idling a little rough, but i thought it was from the cam, now its smooth as glass, or at least like a new truck. Any info is a help. If its screwed, I just may have to convince my wife the motor is gone. Which means a 6.0 Which of course would have to be bored and stroked to 408

Thanks for the help guys. And gals if any chime in.

 

Ok it seems a lot better, but every now and then it still misses, or pulls timing, I cant really tell. Do you think the problem is fixed, and I should just change the oil/filter, and plugs? Or am I missing something?

 

Is the tapping gone?....

 

Yea, the tapping is gone, but the problem came back.......Worse. Now its missing popping, and loosing power at different points in the rpm range.

 

check and see if you did not bend a push rod

 

or cracked a spark plug

 

I rolled the poshrods on a glass door, none of them seemed bent, but 1 had a spot I could tell was rubbing. I'm looking into changing them. I've changed between two sets of plugs, but come to think of it I did drop one thats in there now. I'll probably change them again just to be safe. I want to try to rule out all mechanical problems before I go to Futral or Thunder to get it dyno scanned. I'm going to try Thunder and see if I can get an appt for Thurs.

 

hey white - does it miss at idle at all? try putting a vacumn gage on it and see what it's doing. should be a fairly steady vacumn, probably around 18-20 inches. if there are random flucuations could be valve/valve guide related. a low reading probably an intake gasket. also in your other post you said that you seafomed it. did you pour it into the gas tank, if so may have clogged an injector. if your fouling plugs are they gas or oil fouled? oil fouled=bad rings/guides. gas fouled could be a sticky injector from the seafom or possibly ignition related which will cause a false lean and the ecm will command more fuel. just some suggestions to try and help out.

fwiw - if you have headers and you can make it miss at idle or free rev, spray a little brake cleaner on each tube and the one that does boil off the cleaner is the suspect cylinder.

 

No it wouldnt miss at idle, the only time it did it was when it was warm, and under a load. I finally tracked it down to a bad plug wire, but it dreve me crazy, cause it did the same thing with two different sets. My factory ones, and a new set of MSD's. I decided I would change wires, O2's then buy a new motor, but it got fixed wiht the new wires. Was looking forward to 408!!