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Cam installed 1.6 rr install think i have a bad rocker adjustment

1K views 6 replies 3 participants last post by  96rmlt1sedan 
#1 ·
Just got everything in place dropped my motor back in car with custom Lloyd Elliot cam summit 1.6 rr Comp hardend push rods 26918 beehives and pcm for less tune. I adjusted valves on the engine stand using spin the pushrod method to find zero lash then going half turn pre-load I would go almost half turn then screw in my poli lock tight as I could with Allen wrench then complete my half turn to make the lock bite in I used 1 tdc set closed valves then spin to 6 tdc set closed valves. Engine fired right up first time little valve train clack for a min or two then got nice and quiet I'm assuming after everything got oil and lifter pumped up it sounds good at idle very little tick coming from valve covers not loud at all but here is the problem it starts to run rough as it warms up and I tried to drive it up the street it's popping out the pass side exhaust over and over again like a gun shot sounds like a Harley out that one side no power not drivable but at an idle miss is very suddle and valve train does sound good pretty quiet aside from a very slight tick that occurs on and off at different times.. any advice I'm thinking valve adjustment is off and am thinking to try to re set the rockers while the engine is running does it seem like I'm on the right track thanks for any help sorry bout long post wanted to be detailed with Wat I've done..96 Buick roadmaster heads converted for screw in studs..
 
#2 ·
After re adjusting the valves using the running method, you need to put the car on an obd 2 scanner or scan program.

Read codes as some don't light the service engine soon light.

Also use an obd 2 scanner or scan program capable of doing running sensor data. Since your car runs well when cold, but has problems when hot, I suspect your running problems have to do with car entering closed loop operation when warm.

Because you modified engine, you probably need to have your computer tuned. Could be cause of trouble also.
 
#3 ·
I use the # 1 TDC, adjust the various I/E valve, rotate engine to #6 TDC and do the same . But "spinning" the PR to determine zero lash is not what I do. You are prone to go past zero lash that way. Do the up/down method where zero lash is when no more up/down movement of the PR. Then 1/2-3/4 turn past zero lash.

As noted you need a PCM tune for the new cam or the motor will not run as well and tend to stall

The running like crap once warm...something going on when you get into closed loop so you need to scan motor for data

confirm you have your plug wires on right
 
#4 ·
I had the pcm tuned by pcm for less I sent them all the cam specs and all the info on parts and stuff so the tune should be good Keith wenzel was the one who tuned it.

I actually got underneath the car last night in the garage to check some things out and noticed I broke the plastic connecter to the rear o2 sensor prolly during tranny swap there is 2 on each side..
Could that one sensor not being plugged in really make it run like that and be undrivble with constant popping and no power. Mabey I should fix that b4 any adjustment to rockers guess I haven't run the car enough to throw the code yet but I will scan with my reader tonight see Wat else I can find.also if I decide not to set the rockers while running I hear it's pretty messy I will go back and try the up and down pushrod to find zero lash.
 
#6 ·
Yea I had the timing cover off wen I put the cam in and lined the dots up and spun the motor bye hand to make sure the lined at 12 and 6 and straight up at 12 and 12 and I'm sure 100% the wires are on correctly I did them one at a time on the engine stand looking at my other lt1 and verified with the wire diagram in my GM shop book for Capri Buick and impala the big red books..if I unplug the front 2 o2 sensors and send it into open loop and try it out if it is a problem with that one being unplugged would that be a way to trouble shoot it mabey it might clear up abit?
 
#7 ·
Now that I think of it that would make it run worse if I did that keep it on high idle for warm up..any how thanks for the help guys I'm gonna go check some things again tonight mabey pull a valve cover on that one side and see if anything is wrong with the rockers and I'll run a live scan..
 
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