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94CivicVX · 03-15-2013, 08:02 PM

PROBLEM SOLVED!!!!...

So after going over everything again and again, I took off the valve cover and realized that the timing plates on the rocker arms were damaged. There are little tabs on the timing plates that sit on top of the primary rocker arms. The tabs butt up against a casting on the rocker arm caps. These tabs allow the car to disengage VTEC once it is engaged. The tabs on mine were all broken off!!

I had to change all the timing plates. (They must have been damaged by students since the engine spent it's entire life at a technical college). I didn't realize they were messed up when I originally put the engine together. When the valve cover was off I could see that the primary rocker arm pistons were all engaged into the secondary. A flick of the spring by hand disengaged the little pistons in the rocker arm, freeing the primary rocker arms from the secondarys.

So what was happening is that the engine was constantly in VTEC!! This caused it to run with a stumble in leanburn. It's surprising how well it ran overall considering this issue, but now it runs PERFECTLY.

Can't wait to see how the mileage will be!!!

Note: It doesn't look like a catalytic converter is necessary for proper leanburn operation. I have installed an innovate LM1 wideband 02 sensor right beside the OEM sensor and the car is entering leanburn just fine with no stuttering or problems. (I drilled and tapped the OEM manifold right beside the stock 02 sensor. )

Thanks to everyone for their suggestions!

03-15-2013, 08:02 PM	#19 (permalink)
94CivicVX EcoModding Lurker Join Date: Dec 2012 Location: Canada Posts: 8 Thanks: 1 Thanked 0 Times in 0 Posts	PROBLEM SOLVED!!!!... So after going over everything again and again, I took off the valve cover and realized that the timing plates on the rocker arms were damaged. There are little tabs on the timing plates that sit on top of the primary rocker arms. The tabs butt up against a casting on the rocker arm caps. These tabs allow the car to disengage VTEC once it is engaged. The tabs on mine were all broken off!! I had to change all the timing plates. (They must have been damaged by students since the engine spent it's entire life at a technical college). I didn't realize they were messed up when I originally put the engine together. When the valve cover was off I could see that the primary rocker arm pistons were all engaged into the secondary. A flick of the spring by hand disengaged the little pistons in the rocker arm, freeing the primary rocker arms from the secondarys. So what was happening is that the engine was constantly in VTEC!! This caused it to run with a stumble in leanburn. It's surprising how well it ran overall considering this issue, but now it runs PERFECTLY. Can't wait to see how the mileage will be!!! Note: It doesn't look like a catalytic converter is necessary for proper leanburn operation. I have installed an innovate LM1 wideband 02 sensor right beside the OEM sensor and the car is entering leanburn just fine with no stuttering or problems. (I drilled and tapped the OEM manifold right beside the stock 02 sensor. ) Thanks to everyone for their suggestions!