Thread: Heavy Isolated Misfire Under Load

I've come this far, I'm not gonna give up.

Swapped the injectors around for ****s and giggles. No change still missing on cylinder 1.

maybe ill get the puller back in spring

It has to be a lifter. Its the only other possible thing I can think of.

Or that fubared cam of yours. ....

yeah thats always possible too. damn you pedestal!!!!!

I know its possible. I looked at it through the lifter hole and it looked fine. And the roller on the bottom of the lifter looked identical to the others. No damage or scaring.

No metal in the oil either.

Pulled the valve cover again today. Pulled the fuel pump fuse and had a friend turn the engine over while I watched the rockers movement.

When comparing the "troubled" rocker with another, they seemed to be rocking the same distance down. ... I know I should use a dial to measure for sure.


Anyways, this leads to believe the cam is fine and the lifter isn't pumping up.

If the lifter wasn't pumping up.. wouldn't that cause movement to be impaired?

When the engine is on and pumping the rest of the lifters with oil, yes the one not being pumped up would be impaired.

However, with the engine off, they shouldn't be pumped up. Therefore making the rockers look like they're all moving the same.

Put a new lifter in today. Took it for a quick ride. Went wot a few times. And it felt good.

Came back home put the new pulley on and the second time I went wot with the new pulley it started to misfire again.

I wanna say its the cam but I checked the height the lifters were rising as I turned over the motor and everything checked out. I marked the highest point on the lifter on a different cylinder then swapped the lifter over to the suspected bad lifter. When I turned it over it came up to the same spot.



Damn this car man.

I dont think so, its oil sitting in the top. Thats the lifter from the good cylinder moved to the bad cylinder.

So bigger pulley......no misfire......smaller pulley...misfire. Seems you have your answer right there......you don't have misfire......you have detonation issues. Betting your pistons and combustion chambers are all carboned up causing this. In simple terms, your combustion areas and pistons are so carboned up that the compression ratio is through the roof. Bring the car to normal operating temp. Get a squirt bottle full of ice cold water. Spray said ice cold water into intake and let it blow the carbon out as you rev it by hand.

The other option is to run your tank dry and put true racing fuel in it. Bet your issue goes away then.....as per previous paragraph.

Im open to new ideas, however I don't think that is the case here. I'll admit when I pulled my head 2 weeks ago all my pistons were pretty dirty(see page 3). If that was causing it then all the cylinders would be missing or "detonating". Besides, I'm not really seeing any KR.

Spend a little money and put racing fuel in it. See if it goes away.

Also, your #1 hole looks worse than the other two. I know it may not seem like much, but, remember, it only takes a .030" bore over to turn a 350 into a 355. Since the machining of that era still was not the best, any extra buildup in the chamber could have an adverse affect on it.

Everything mechanical seems fine then. Going back to what bill said earlier...You have a huge vacuum leak somewhere...or something electrical.