To start off- Car was fine.

I installed a aggressive MIVEC map that gained me 1000 rpm's of spool, she spooled at 3800 vs 4800... but she knocked her *** of. Everything was fine up until this point.

So I switched back to my normal map.

Never stoped knocking. It knocks under any boost. I have logged as much as 14 counts..

So I pulled timing (14 max) - turned boost down to 19 psi (fpred) - added fuel (10.0)

Still the same.

I pulled the plugs- number 2 was WHITE. all others were loaded with fuel.

SO i sent my 900'c off the DW. The injectors tested ok. all within 3%. I had them cleaned and blueprinted and now they are within 1%.

I installed the injectors and a new intake manifold spacer/gasket.

Shes still knockin and that cylinder is still white as hell.

What do you think is going on?

is it possible that with the mivec map, i nicked a valve causing air to leake in when the valve should be sealed and leaning it out?

 

Aggressive mivec, makes the fueling during spool up really lean... so the fuel map has to be adjusted to dump fuel during spool up 2-3 points less than most of the rest of the map.

Check the spark plugs if they are all firing or replace all 4. I'd check compression, should be about 150psi across the board on a very hot motor.

 

have you pressure tested and covered all of the bases?

cb

 

Do you have a wideband?

Scorke

 

all 4 are firing. I had plugs go bad and as "missfire" is very obvious. and if it was not firing, the cylinder would be black from the unburned fuel. also, the afr's were fine when i ran that angry MIVEC map. Logged with my aem wideband

the only bas ive covered so far is testing the fuelinjectors. WHats a possible outcome? where is the fuel going?

Yes, AEM.

 

Could something be clogging the fuel rail?

I ask because the fuel rail is the last part that could change how much gas each cylinder is getting.

 

the fuel rail lets gas flow through a pretty big opening, i guess this could be the case, I wonder if the FPR unit has gone bad, possibly that one injector is just not getting enough fuel to pull from?

I have a AMS Fuel rail, stell braided lines on a stock FPR.

 

His WB02 should verify rich A/F's, which I assume he did....

If A/F is rich (10:1), Mivec is stock, and timing is stock, then I would Comp check and borescope the motor.

 

my car is far from stock. As you might see in my Sig... Current mivec setting is not stock, but its been working for over a year, I just wanted faster spool up since ive seen mine is one of the slower spooling cars.

 

I understand, but put it back to stock and see what happens, sure you'll lose spool, but see if it reduces knock...

 

You mean put the stock mivec map on the car? Considering ive been running this mivec map for 12 months with no issues, I do not believe it "all of a sudden" stopped working.

I tried a new mivec map last week, it knocked, i removed it, it kept knocking.

I have already narrowed the problem to a cylinder, being teh one plug that is chalk white and all other plugs are black.

Now I just need to figure out whats goin on inside that cylinder

 

did you check the other threads about knocking?

 

Just do a damn compression test... sigh. If you get bad result then boroscope it...

 

^ x2

 

i know.... gonna try to swing by All Aspects monday and do one.... i was just hoping for someone to say they have seen this exact issue before.