My compression test results.......

[Silent Drifter]

I did a copression test the other day, an from what ive read normal is 179 but my numbers were all from 185-195. I also have a DE if that matters. I was wondering if the higher compression is good bad or just doesnt matter. Thanks

[stash420sx]

I just ran mine the other day and I got 75/160 for all four cylinders. That was a static compression test. I disconnected the fuel and spark. Removed all spark plugs, and held the throttle open. I did three puffs.

[Checkered-Member]

I did a copression test the other day, an from what ive read normal is 179 but my numbers were all from 185-195. I also have a DE if that matters. I was wondering if the higher compression is good bad or just doesnt matter. Thanks

How does your fuel map look like?Are you running rich

[Silent Drifter]

I dont know how to check the fuel map, but I seem to have a lot of carbon build up out the exhaust, so I assume Im running rich.

[Checkered-Member]

I dont know how to check the fuel map, but I seem to have a lot of carbon build up out the exhaust, so I assume Im running rich.

Hmm…sound rich to me. You can invest 70 bucks for air/fuel ratio gauge, that will tell you for sure.A few good once can be found here:http://www.modacar.com/product...DAMET

[Asleep Altima]

jeez, he drives me crazy... (checkered-member) dont go buying any gauges, its a reference at best. those numbers look good to me, without knowing exactly what the tolerances are. any variance of 25psi or more between cylinders indicates a bad cylinder or at least, a cylinder with problems. as far as running rich goes, when was the last time you changed your oxygen sensor and/or your air filter? a clogged air filter will richen up the mixture since air is restricted from entering the intake.

[Checkered-Member]

a clogged air filter will richen up the mixture since air is restricted from entering the intake.

not true, your thinking of carburetors engines, fuel injection will compensate for the lack of air by dropping the fuel mixture.

[Silent Drifter]

Its a brand new KN filter. No idea when O2 sensor was changed, but why would that affect the compression? especially when the car isnt even on.

[Asleep Altima]

your numbers were good. why do you think theres a problem?? be happy theyre high. and checkered, dont tell me what im thinking. ive forgotten more than you know.

[Altiman94]

I agree with asleep. Those numbers are right on. My altima when I had it (ka24de) were all at 180, or there abouts. My ka24e s13 were all at 150-155. I'm havnig a rebuilt motor putin, so I'll check the compression of that motor when it's installed.

[RobDET]

if you are running ritch you can get carbon buildup over long periods and it can cause higher compression. I'm sure thats what he is talkin about

[Silent Drifter]

O ok, do any of you know what I can do so Im not running so rich, though I rather run rich than lean:)

[RobDET]

on a NA car the lean/ritch thing isn't as big of a deal. If you want to run slightly more lean i'de look into replacing the O2 sensor and checking the AFM voltage... Also TPS voltage...

You should also go through the steps to properly set your idle and base timing.

Any of those tihngs being out of spec can result in unburned hydrocarbons.

Also does the car use oil?

[LiU]

josh and kirt (real nice ppl, friendly and easy going, they're based in ATL, so check em out) over at http://www.drift-racing.com did it for me, I got 120~ on all 4 cyl... this is on a 96 KA24DE w/ clsoe to 110k miles... I am puzzled at the low numbers because my car pulls like a beast with #s that low it just seems weird. and the motor has been taken pretty good care of so...

here is how we did it, unplugged 1 plug at a time, plugged in the gauge, i cranked the car, and got a reading. repeated for all 4 cyls and got 120~ on all 4. Josh thent ested the gauge and said it was fine (its brand new). Can any1 tell me what might be wrong?

oh yea we were testing my motor for turbo... i need the boost, those bolt ons just aren't cutting it anymore

EDIT:I did a search and found out stuff like you hafta disc. fuel pump fuse, take all plugs out, and be on WOT or somn... maybe that's why my readins were low... at least they were consistent

[DAEDALUS]

You should have all plugs out too. This will allow the pistons/crankshaft to move faster since the starter doesn't have to work against compression in all cylinders. Make sure the plug recesses are clean before you remove the plugs, or dirt and crap will get sucked into the cylinders. Worst case, could be a small screw or washer you didn't know was down there.

[Silent Drifter]

Also does the car use oil?

Yea it burns oil.

[RobDET]

ahh that is why your tailpipe is black... i wouldn't worry... your car sounds fine...