00blackz71

I just did a cam swap with the vinci 80 ultra torque. 210/218 .551 116 I also added the crane 1.8 rockers and a nelson tune. I have adjusted the rockers serveral times and always had them too tight. The last time I thought I had them right but now it barely idles, sometimes it will go dead when I let off the gas and I can't get it over 40 mph and has no power. I haven't checked the compression yet but what should the compression read for a motor with stock pistons and heads on a 5.3? I figure if ones is too tight they are all probably too tight. Would the rockers being too tight be what is causing this or should I be looking for something else?

I just checked the codes and getting 351,353,355,357.

PappyDan

iTrader: (4)

under what conditions did you adjust the rockers?

00blackz71

Followed the instructions. Zero lash and 6 - 1/4 turns waiting 10 mins between each 1/4 turn. What would be throwing the codes?

PappyDan

iTrader: (4)

what rocker was to be used with your cam for the 551 lift, i see you added 1.8 rockers.

budhayes3

iTrader: (19)

A couple of guys have had problems adjusting those rockers. You could try putting it together with the stock rockers on and see how it runs...if all's good, you know that you just have to nail down 1.8 adjustment procedure.

thunder550

iTrader: (70)

Yep, I overtightened the rockers the first time I did them too and left valves hanging open. Wouldn't start. Put the stockers back on and it ran fine. Tried the Crane 1.8's again a few days later. Follow the instructions to the exact letter. when they say "lightly lift" up on the rockers to determine if there's zero lash, it means lightly, like barely touching them. Go back to the stockers and see if you can get started, if so, then yeah that's your problem and all you have to do is re-install them. Good luck!

00blackz71

I really don't believe that they are too tight. When I adjusted them I barely tapped the rocker really not even picking up on it at all for zero lash. The motor will start and idle fine but if I put gas to it and let off the idle will go up and down until it settles down again. When I drove it, it had no power and wouldn't rev past 2500 rpm. The codes 351,353,355,357 say that I have an ignition coil primary/secondary malfunction. I changed the computer at the same time and I am thinking that it is a bad computer. Is there any way that the rockers being out of adjustment could cause the codes I am getting?

PappyDan

iTrader: (4)

check all of your wire connections and make sure they are right.
did not know about the pcm swap.

Okie5.3

iTrader: (1)

are both coil packs plugged in? how about the crankcase ventilation tube from the throttle body to the passenger side valve cover? did you verify 0 lash, rotate the motor by hand 1/4-1/2 turn and rechecking each rocker, repeating another time or two until all are at 0 lash? it also should be 8 - 1/4 turns of the poly-nut. this will net you approx. .080" lifter preload.

O3GMC

How did you get the crane studs out to put the stock rockers back in? I've been wanting to try the stockers but I locktited the studs in, and dont want to get in there only to find out I can't get the studs out, and repeat the whole adjustment procedure again...


00black - Did you make sure the cam /crank gear dots were lined up? With those codes, sounds like a pcm issue to me... http://gearchatter.com/viewtopic10691.php