I just swapped a k20a2 into my car two weekends ago. Everything went fine, had the fluctuating idle but that went away in a couple days. It pulled hard and I thought everything was perfect. A day or two after that, it started misfiring. Replaced the plugs with Denso Iridiums and no difference, CEL came on in a couple minutes.

Cylinder #4 (I think it's #4 - it's nearest to the tranny) was completely carbon fouled within 100 miles on the plug. Plug IS sparking. I tried a new plug in that cylinder and it was carbon fouled after a couple minutes of idling. Swapped injectors with a k20a3 injector, still no power. I put the a2 injector back in and gave up - it was 2am.

So it seems to be getting spark and gas but cylinder #4 is running rich. I have a SRI and full exhaust. What could this be? (I can't afford to get it tuned right now)

I'm going to do a compression test but I doubt that cylinder has low compression because the motor was pulling hard for a few hundreds miles.

 

Have you tried pulling fuel out of the cylinder using the individual cylinder trim, just to see if it was affected?

- Derek

 

I'm sorry but I don't know what you mean. Could you explain what I should try?

 

Are you running K-Pro?

- Derek

 

No the vehicle is a 2002 Civic Si. I'm using the rsx-s engine harness and rsx-s ecu. Engine is stock, and this swap shouldn't need tuning. I seriously cannot afford kpro right now. It's like $1500 with tune!

 

I did the compression test. Please note that I used a $15 compression tester I just bought from Harbor Freight and this is my first time doing the test alone. I tried letting each cylinder crank 5 times but I can't be certain since I didn't have anyone watching the needle jump.

(Pulleys side) - 165 - 165 - 160 - 160 (tranny side)
I bolded the cylinder that is fouling plugs.

Here is the plug (has about 60 miles on it since I cleaned it last. About 250 total miles on it):

 

Install some new fresh plugs, and try swaping your injectors around i.e. cyl 4 to cyl 3 to see if the injector in cylinder 4 is spraying more then the rest etc...


Get your self kpro and a tune....

 

Like I said, the plugs are all new. The problem is NOT the plugs. The rich mixture is carbon fouling plugs within minutes of idling. I swapped injectors with a k20a3 one and it ran the same.

This swap does not need kpro and I don't have $1500+ right now...

 

Bump

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mtber &raquo;</TD></TR><TR><TD CLASS="quote">Install some new fresh plugs, and try swaping your injectors around i.e. cyl 4 to cyl 3 to see if the injector in cylinder 4 is spraying more then the rest etc...


Get your self kpro and a tune....</TD></TR></TABLE>
do what John sais! Swap it to another cylinder and see if the problem moves.

 

I have. The problem is that cylinder, it doesn't move with components. This leads me to think it's internal BUT the compression isn't low... ARGH

 

What injectors are you running? You mentioned swapping them with the k20a3. k20a3 has 270cc injectors while the k20a2 is 310cc. You want to make sure that you have a matched set of injectors.

Have you checked the coil to make sure it is working properly? Maybe try swapping the coils around and see if the problem moves. Maybe the one on cyl #4 is dying.

Have you checked your valve adjustment. Just a wild guess since you say the problem doesn't move with the plugs/injector. Maybe the valve lash is way off on that cylinder and it gets significantly less air than the other cylinders. If this is the case, then I don't know if the compression test would show this problem.

 

Yeah I adjusted the valves yesterday, they weren't off too bad. Actually, cyl #2 was the worst.

I also figured out that 1 of the injectors is malfunctioning. Even though I thought they were all good, the problem is now moving with the injector that was in cyl #4.

So I'm getting new injectors. Are these overkill? http://www.clubrsx.com/cr/PTE-...=fuel I'm not tuned but these are cheaper than stock ($108 each). I'm going to supercharge eventually. Will these be okay? Will it run rich or waste tons of gas?

 

Those are too big to run on the stock ecu. Just get some more factory injectors beat you could pick up some used ones cheap. Also did you open the throttle when doing the compression test "it usually takes more then five revolutions" those numbers seem a little low.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sr420Det &raquo;</TD></TR><TR><TD CLASS="quote">Those are too big to run on the stock ecu. Just get some more factory injectors beat you could pick up some used ones cheap. Also did you open the throttle when doing the compression test "it usually takes more then five revolutions" those numbers seem a little low. </TD></TR></TABLE>


agreed.

 

Leak down time!