Banging, running like shit!!

[MattM]

could the vanos unit cause that?

The coil connector are pretty much impossible to get backwards on OBD2 harness

and yeah, the noise sounds exactly like that video, but not nearly as often

[sohc12vm20]

I heard the noise better in your video and I still believe its not mechanical, again I know this is not much help sorry, but I do think from my experience its gonna be related to ignition timing or at least in that ballpark. Whatever it may be, I cant wait to see whats causing this knock is.

[e46s54dr]

Its a slim possibility but can it be that youre running old/bad gas? My e46 had an erratic idle and what sounded like a rod knock when I ran old cheap gas that I had in my garage that I usually used on lawn equipment. As soon as I pumped a fresh tank and disconnected the battery to reset the dme, the sound went away.

[Ryann]

The "banging" sounds like popping in the intake manifold to me, like a carb'd car does when there's a massive vacuum leak or the spark timing's fucked up.

[butters]

The "banging" sounds like popping in the intake manifold to me, like a carb'd car does when there's a massive vacuum leak or the spark timing's fucked up.

good thought, reminds me of my experience with a ZX-6RR with standalone ECU and custom intake with fuel rail. when we were working out the kinks, I discovered that a relatively common issue was fuel buildup at the wrong time and pooling in the cylinder after shutoff. press the starter and a large explosion was ignited. akin to what people have been saying about screwed up spark timing, which could then cause misfires to be audible through the intake.

[MattM]

a guy on a another board suggest i unplug each coil 1 by 1 to see if it makes a difference... heres what i found

if i unplug any of cyl 1,2 or 3 it makes no difference... If i unplug any for 4,5,6 it runs REALLY rough until i plug them back in... the banging never goes away.

Also, when i run without the MAF it basically doesnt rev... it will die if you move the throttle too fast, and if you move it slowly you can get it open, but the engine doesnt respond... with the MAF plugged in it revs, but it wont stay running unless u keep it above 1000rpm

[butters]

if i unplug any of cyl 1,2 or 3 it makes no difference...

hmmm... that's not good.

swap ECUs if you have the means. test the heart of the beast?

[MattM]

i have swapped the ECU's, no real change. I have 2 ECU's now...

[Ryann]

Are plugs 1, 2 and 3 fouled? Have a look at them.

[MattM]

Are plugs 1, 2 and 3 fouled? Have a look at them.

nope, randomly swapping plugs and/or coil packs makes no difference..

[trackjunkie21]

something seems fubar'd in the harness, have you tested it?

[MattM]

using GT1 i have tested each injector, and every moving valve on the engine, they all respond.

The engine harness is about the last thing left i have not replaced besides the block and the head... those might be next....

[Ryann]

The engine harness is about the last thing left

So what do plugs 1, 2, and 3 look like after you've run it for a bit?

Have you tried turning the car over with a plug stuck in the end of a removed 1/2/3 coil to see what/if anything was happening? You'd have to ground the outside of the plug on something..

[MattM]

all plugs spark when pulled. They are just slightly damp with fuel...

The header bank for cyl 1,2,3 only gets warm(i can rest my fingers on it), where as the header bank for 4,5,6 gets smoking hot(normal?) after running for a minute.

The banging sounds consistently like its coming from Cyl 3 area...(where my dad puts his hand in the vid)

[Ryann]

Have you put a vacuum gauge on it? I have exactly ZERO 24v experience, btw. Just old school approach.

http://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm