qtiger

What's your knock look like

Mario

No clue to be honest.

I borrowed my neighbors compression tester and got these numbers. I pulled the ECU fuse, and cranked 6 times: 134, 130, 135, 135

Tried it again 10 minutes later and got 70, 130, 135, 135
Tried it again and got 75ish, 130, 135, 135
Tried it again got 90, 130, 135, 135
And last time got 94, 130, 135, 135

qtiger

You weren't bubbling your coolant on the dyno, were you?

Mario

I don't believe so.

qtiger

Okay, so you're running a stock ECU now, with a VAFC, yeah?


What ECU are you running now, and what ECU was chipped?

Mario

Yes, AFC with JDM P30 ECU.

The ECU chipped was a P06.

b16ahybrid

Those numbers seem kind of fishy....
Man if you were getting a consistant 70ish on that one cylinder I would say drop a bit of oil down that cylinder then run the test again, but your number is all over the place so it's hard to say.

btw I wasn't recomending a larger turbo as a solution to your low number problem, there is something obviously wrong, but what it is i'm not sure..
I still think it looks like your engine is missing with the chart being so choppy.

critter sit-t

not to jump in here but ill put my input in. i built a b16a2 for puerly turbo app. it had 8.5:1 compression pistons in it. It ran ok but lacked power due to the low compression ratio (not saying that thats your problem0 I took my car to a shop to have the vtec controller installed and the car dynoed and the shop ended up messing up the motor really bad ,so I thought< I was getting the same stuff you were getting on your charts after Vtec kicked it went hay wire. I ended up pulling out the motor after a compression test reveiling that #3 had no compression at all. it ended up one of the valve guides had a small burr in it which was causing the valve to not operate proprley. I went throught the entire motor finding nothing else wrong so i put it all back together and all my power is back, i had to reset the vafc cuz the shop is retarded and dosnt know what there doing but other than that i went through all that for a burr in a valve guide. im not saying that thats your problem at all but you might check it out. test your piston rings they make air fittings that screw on like the compression testor to tell you if your getting blow by or not. the car is going into the shop next week after the fmu comes in and its getting dyno chiped and turboed. yaaa. well good luck i hope maby this gives you another aspect of things.

raiden571

pull the haed off the block and drop the pistons. you probably have blown ring lands. there not that expensive and it isnt that difficult to do, just tedious. the trick is to take your time and while your at it, you should atleast get a ball honer and redo the cylinder walls to get tahat nice cross-hatch effect for good ring seal

Mario

Thanks guys... I ran a compression test again and am at 135psi across all the cylinders. It's good to see that it is at least constant now... I know the numbers are still low however.

I do have a question: would an unusually low compression cause any special oil characteristics? The oil still looks fresh, and I am not burning absolutely any at all. (last oil change had 4qts new oil, and after 4,000miles all 4qts came back out).

Apparently a 99-00 Civic Si and a 1995 del Sol VTEC distributor cap does NOT fit my motor... I can't explain to you how frusterating this is. Once I do that I have new rotor, cap, and plugs going in... and hoping this will help my misfire problem so I can at least get the car tuned.

Thanks a bunch guys.