EGR, Cylinder #3, and Backfire

[Blown&Injected]

I am trying to figure what is causing the induction backfire. Brand new fuel system and lines but I need a gauge with a long enough line to read while driving because I think it is still leaning out.

Car has ALKY and that seems like it can make an induction backfire something extra special and the last one blew the head gasket.

The EGR is blocked off and it looks like there is still a clear path from the #3 exhaust port to the intake manifold but that is where the block-off plate stops the exhaust flow – right? I blew the Head Gasket on the #3 cylinder and my mind is just knocking ideas around…

I am gonna pull the #3 rod cap and take a look at the bearings – the oil pan was clean except for a bit of junk from the graphite head gasket.

New coil and vacuum lines but the module is at least 15 years old – might be the one that came on the car in 86!!!! Car has been driven just a few times per year for the last 10 years. Don't know what else to consider???

Oh yeah, the PVC is also totally blocked off, I just have big breathers, one in each valve cover. I did not want any dirty air in the intake - maybe I went too far???

 

[No disintegrations]

Any problem with the number 3 cylinder makes me wonder about a wiped out cam lobe since that one is highly prone to failure.

 

[rag231]

Pull the valve cover and check that rocker for movement. If there's no movement on the exhaust valve from a wiped lobe there is only one place for it to go, back out the intake valve. Unless its barely moving to squeeze out a little fuel. What gauge are you intending to get fuel pressure, air fuel, scan master? Around how much boost were you getting to get the back fire. What other tuning device do you have? Stepping into ALKY without them is a big risk. Any idea if you're running a flat tappet cam? If you don't hear any rod knock , I probably wouldn't waste my time pulling caps. The bottom end can take a few beatings from detonation.

 

[dank GN]

Bad coil ? Cam sensor not set right ,

 

[Mike T]

Every time that I've lost HG's #3 has always been worse than the other cylinders. Same for a friend of mine as well.

 

[Mike T]

Let me back peddle a bit on the above statement 3 and 4 have been equally as bad for me.

 

[Blown&Injected]

The roller cam looks fine - I have had lots of #3e fails - the ONLY lobe failures I have ever had (I am no engine builder but have done many cams in many different engines and the only fail I have had is the #3e on the Buick)

Got a new Coil - maybe the module is freaking out???

Also worried something is not right with the EGR block - off. The floor of the Intake is not sealed off.