low boost after check valves popped out

OK Guys, my check valves popped out of my throtle body the other night. Ever sence then my 2000 Si with RevHard kit has ran like crap. I've checked and changed the plugs, checked the oil, and looked for leaks. The car idles fine, doesn't miss, no strange noises, runs rich when on the gas, but I'm only boosting 3psi instead of my usual 7psi. Any one got any clues?

The first thing to check would be if the system is properly sealed, make sure there are no leaks where boost can leak. Make sure the are no exhaust leaks where exhaust gas can circumvent the exhaust turbine. After that, if everything check out, take your turbocharger out and check to see the wastegate is properly working, it may be stuck open. At the same time check for damage to the compressor, and turbine. After checking these, if you still aren't making full boost, post back.

Check valves are GARBAGE. Switch to a MAP Off an Ex Civic, or get a GM 3 bar. Don't use a check valve. You probably have a boost leak somewhere. Check all your connections and piping. Also, revhard kits have a nasty habit of cracking manifolds.... check that out whil e your at it.

Thanks guys. I'm with you Cronic, check valves suck. My missing link is on its way. I'm also showing an error code 5. I believe thats "low vacum/high vacum" code. My internals are my main concern. Do you guys think theres any chance that I really screwed something up on the inside?

DONT buy a missing link either.. it's the same damned thing as a check valve.... ugh.

Return it.

Yes, there's a possibility you f'ed something up. I'll grab my book when I get home and check that CEL code.
If your worried that much. Goto Autozone, or Discount, and buy a compression tester, and 1 qt of oil. Any wt will do.

Remove all your spark plugs, and disconnect your fuel pump fuse.

Do a compression test. (IE< Screw the tester in there and crank the motor over)
Write down your numbers...
There should be less then 20psi variance between every cylinder.
After this, start over from cyl 1, add 1 capfull of the oil, and test again in each cyl.
If the compression jumps up over 50psi, you have a compression issue. It shouldn't really jump very high if your rings are good.

Once you start your car back up, it will smoke for about 10 minuites very bad. This is normal, as your burning the oil out of the cyls.

Thanks and let us know.

Thanks Cronic. I plan on doing a compression test this weekend when i have time. (she'll just stay parked till then) I really don't think, or atleast pray, its anything internal. I believe its a MAP/vacum thing. If you come up with anything else, please let me know.

Don't feel bad. My oil rings finally went yesterday. Building a stock block as we speak, and this block's going to GEM in a couple weeks.

CLOGGED CAT! After checking compression, adjusting vaulves, testing wastegates, swaping BOV, the damn cat was stopped up. When ever my check valves poped out, the map sensor just told the ECU to dump as much fuel as possible into the engine, running way rich, and clogging up the converter. Race pipe here we come! Thanks for the help guys.

I have a 99 si and was thinking of purchasing the revhard 2C kit, which stage do you have ,do you like the quality of the kit?

I have a 99 si and was thinking of purchasing the revhard 2C kit, which stage do you have ,do you like the quality of the kit?

I have the stage 2 kit with upgrade turbo from the 2c kit. I love it so far.
I haven't had any problems from any of the stuff that came with the kit. Get ready to do a little cutting along the way, but no biggy. I few bugs here and there with the car, but none from the kit itself. I don't know what sort of upgrades you already have, but if you don't have atleast a stage 2 clutch of some kind, you might as well buy one and install it while you have the car on the stands.

yea, i will definately need a new clutch, and the money to buy the turbo kit.