3.0 Tapping Noise

[81dmc]

Ran some more today, and can definitely hear intermittent and very slight misfiring pops from exhaust.

[Bitsyncmaster]

Ran some more today, and can definitely hear intermittent and very slight misfiring pops from exhaust.

I always though my engine had the same "very slight misfiring pops". But I put some software into my idle ECU to detect a misfire which checks every two ignition pulses and triggers if that time is outside +/- 50 RPM and my engine can idle for 5 minuets without any hits. So that popping sound you hear may be something other than a misfire.

[MrChocky]

I always though my engine had the same "very slight misfiring pops". But I put some software into my idle ECU to detect a misfire which checks every two ignition pulses and triggers if that time is outside +/- 50 RPM and my engine can idle for 5 minuets without any hits. So that popping sound you hear may be something other than a misfire.

Obligatory sewing machine sound effects.

[AugustneverEnds]

Does your car have a catalytic converter? Perhaps it's partially plugged? The manifold gaskets might be beginning to leak. Fun job!

Is your EFI mapping dialed in? Maybe the mixture is slightly off.

[81dmc]

I always though my engine had the same "very slight misfiring pops". But I put some software into my idle ECU to detect a misfire which checks every two ignition pulses and triggers if that time is outside +/- 50 RPM and my engine can idle for 5 minuets without any hits. So that popping sound you hear may be something other than a misfire.

Maybe you're right. I just also get some vibration when it's doing the micropops. I may run a test harness and swap to the eagle premier coil pack instead of COPs.

Or maybe I got a bad EDIS module

Does your car have a catalytic converter? Perhaps it's partially plugged? The manifold gaskets might be beginning to leak. Fun job!

Is your EFI mapping dialed in? Maybe the mixture is slightly off.

Cats are new DPI high flow, and I have new manifold gaskets on order. I probably toasted the gaskets as I ran the car for about an hour then I found I forgot to tighten the header studs .

Overall, mixture isn't done yet, but in the video, it was idling around 14 afr and 14* of timing. I messed with the AFR and it didn't effect how it was running much.

[81dmc]

Tried the Monaco coil pack with no change. Drained oil after 35 miles of driving. Oil had a definite dust of metal. Was a 10w30.

I changed it to VR1 20w50 and the idle oil pressure went from 14 to 22 psi. Big improvement there. Cam lobes still look good from oil fill hole.

I will experiment with the exhaust gasket, EDIS, and injectors next to determine my issue. Will also try running with only headers to see if that?s my vibration.

[Ron]

Did you try pulling the plug wires one at a time?

[81dmc]

No change pulling injectors one at a time. Also tested injectors and spray looks good.

I read somewhere online that the hydraulic cams are different then solid lifter cams. Anybody know if this is true?

[Ron]

No change pulling injectors one at a time. Also tested injectors and spray looks good.

I read somewhere online that the hydraulic cams are different then solid lifter cams. Anybody know if this is true?

Good, pulling either one should change the sound if the problem is exhaust gaskets, usually.

Solid lift cams typically have faster ramp speeds, lift higher, and need stronger valve springs.

[81dmc]

I wish there were performance cam option for the 3.0. I would?ve put a set of cams in this if that were the case.

Hopefully most of the noise goes away with break in. I guess I?ll find out if it eats the cam or not.