P0351 after cam swap
 

TSo It's 3:30 am and I can't sleep, this jeep thing is driving me nuts, lol. I swapped in a comp cams extreme 4x4 cam, timing set and lifters over the weekend which can be seen at...

http://www.compperformancegroupstore...ode=A6CAMSx4X4

Wouldn't fire at first, was a tooth off on the distributor, no big deal, redropped it and it fired. Sporatic miss. I'm thinking ok, it's just wearing all that protectant off the cam. 15 minutes into break in it starts to tick. Shut it down, pulled the cover off, pulled the pushrods, blew through them, and put it all back together. 10 more minutes it starts ticking again. Still missing of course. Friend put a stethoscope on it and said it was coming from above the head line. shut it down, and checked the codes. P0351. Did not have this problem before I swapped the cam. Any ideas? The tick is at either cylinder 1 or 2

did you read the camshaft specs page at the bottom it states note #7 stock springs cannot be used did you use there springs

maybe the springs are to week that are stock

stock valve springs are to soft for this cam you need to use there valve springs if you didn't in the first place

Their valve springs do not work with 89 and newer vehicles, They won't fit. I called Comp and they told me most people just use stock springs, they don't have a recommended spring. Doing tons of research before I started this install, I've seen guys who say they've been running stock springs with this cam for over 2 years without a problem.

Also... Wouldn't weak valve springs miss the most at higher rpm's, and not so much at idle?

motor full of oil did you torque the rockers down worn rockers

are you sure the ticking your hearing is not a spark tick do you have spark plyg wires or coil packs

Plug wires, it's a 97. The motor has 6 quarts of comp cams 10w30 break in oil in it, and I torqued all the rockers to 21 ft lbs.

wow, page 4 already? back to page 1. I found some knicks in the top of the exhaust valve stem on cylinder 1, looks like they're being put there by a knick off the bottom of the rocker.

Exactly, that's the safest way to break-in a new cam (light springs) and I would think stock springs would cause no issues below 4000 rpm.

Going to attempt to take the burrs off the end of the valve stem and put a new rocker arm on it today, I'll let you all know how it goes.

got the burrs off the valve stem, put a new rocker assembly (2 rockers, 2 pivots, and a bridge) along with 2 new push rods on it. still ticks.

now for my moment of feeling stupid...

get the stethoscope on it again. still coming right from the front of the head, no-where else on the block except right at front... hmmm... lets pull the belt off and start it.... no tick! It was the water pump.

As for the miss with the P0351, my distributor housing had broke underneath the holdown clamp. We all have our moments I guess... new distributor going in tommarow. Will let you know if that takes care of everything. Will be nice to see how this new cam does with my header and intake.

glad to here you found the ticking culprit

Runs like a charm now! It kept missing with the new distributor, until we figured out that you can't go by the alignment holes when dropping the distributor like the factory service manual says, it was a tooth off every time we tried to do that. I don't know of it's because there's maybe an advance built into the cam or what, but it was putting the rotor past number one at top dead center. Re dropped it according to the rotor instead of the hole and she purrs like a kitten now.

Good onya for finding the issues. Those little gremlins can be a bugger.

If I may ask, looking at the cam specs, that is effectively a stock cam, (Which, IMHO, is the right way to go for these motors) why did you have to change it?