DualCamEJ

iTrader: (1)

So my car smokes at idle. I would have to say I took my motor all the way to the rev limiter and start smoking the next day. It takes a long drive to where about 20-25 minutes for it to smoke. It's still a fresh motor from Japan with only 47,xxx miles tops. It's a 99 ek hatch, jdm b18c with a stock p2p single cam vtec ecu. Vtec engages but p2p ecu rev limiter is around 7800ish. Piston rings SHOULD be fine I'm guessing because I never took the motor pass 9k. Ever. So when I hit that rev limiter it might of had too much stress on the seals and must have gotten damaged, almost like an incident that can cause bent valves.

So here's the question, I heard that bad valve seals smokes at idle, and bad piston rings smokes under load. True or False?

Any help would be appreciated. Thank you H-T members.

NotARaCist

iTrader: (1)

First off, what the monkey ******** are you doing running a B18C on a P2P ECU? That right there probably caused your current problems.

Second off, I'll address a very common misconception. "Fresh motor from Japan" is a lie told by all of the engine importers. The truth is, you have no way of knowing how many miles the motor actually has on it. That whole "Japanese cars have to have the engines replaced at xK miles" thing is a complete lie.

As for your true or false statement, false. Valve stem seals usually smoke under load, and rings usually leak...always, if they're bad.

You need to do two tests to get a "general" idea of what's wrong. First, do a dry compression test. This will confirm the damage, and help you pinpoint which cylinder(s) have failed. Second, do a wet compression test. It's exactly the same as a dry test, you just put a teaspoon or two of motor oil in the cylinder before doing the test. Once you've done both tests, post the numbers for all four cylinders here, and we can work from there.

If you have access to an air compressor (even a small air compressor will do the job), you can also do a leak down test. There's a good how-to here.

DualCamEJ

iTrader: (1)

The motor ran fine for about six months with that ecu, no CEL at all. Bypassed the CKF sensor too. Until this point which i never took it to the rev limiter. Good point on the tests, I'll try that to narrow it down rather than jus slap something on. I'll get the numbers posted.

NotARaCist

iTrader: (1)

All other factors aside, The D16Y8 (what the P2P ECU is made to run) and the B18C (both variants) are COMPLETELY different motors. It really wouldn't surprise me if the P2P ECU leaned the **** out of that motor, and detonation decided to break a ring land or two on you.

Once you have some numbers up, we can work from there.

DualCamEJ

iTrader: (1)

Compression test is done and here are the results.

Cyl.1 cyl.2 cyl.3 cyl.4
Dry 210 200 210 212
wet 255 240 240 210

they do seem fine here, ive done multiple tests on each cylinders and this is what I came with. Piston rings seems ok.

NotARaCist

iTrader: (1)

Uh, re-do the test on cyl 4. The number definitely should not go down. Your dry numbers look perfectly healthy, though. There's nothing there to indicate that your motor should smoke at all.

What color is the smoke? Clear, white, blue, or black? Give your exhaust a quick whiff - does it smell sweet, oily, or like you're hanging outside a gas station?

tony_2018

Get the correct ecu and stop playing......You're doing more harm to that engine than you think you know.

DualCamEJ

iTrader: (1)

like a very lightish blue and lil white. once i was done with the all the tests, i did one last test on cylinder 4 and i got the same results. i think its the valve seals

TomCat39

If I recall there is two piston rings before the oil control rings on each piston, you can break one ring and still have compression from the second ring.

The problem with the incorrect ECU is that it's likely to pump more fuel in than needed which in turn can cause cylinder wash.

If you haven't had your car tuned, then the improper ECU can be causing damage that you won't realize until it's too late.

Also, like it was mentioned in another thread, your piston rings can be fine while the oil control rings are shot thus causing smoke while having good compression numbers.

Are you getting the blue tint smoke all the time or just under load after idle? If it's after idling for a bit then getting on it and on no throttle high rpm deceleration then it's more likely valve seals, if it's all the time, load or no load then it's more likely oil control rings.

DualCamEJ

iTrader: (1)

just when It idle it smokes a light blue tint. Also at deceleration, thats when its more white smoke. When I let off the gas in gear

NotARaCist

iTrader: (1)

Light is good. Light means you probably don't have fucked ring lands. Might be bad ring gap, broken rings, or washed cylinders. Regardless, the solution is the same: Rebuild the bottom end, and get the correct ECU. If the smoke is minor, and you aren't losing a significant amount of oil, I would honestly just put the correct ECU on the car and leave it. The correct ECU is extremely important, though. Keep running on the wrong ECU, and you seriously risk blowing that motor way the **** up.

If you decide to rebuild the bottom end, it's a fun process. I'm actually in the middle of it in my project thread, if you're curious for a how-to/DIY, but get a factory service manual for the motor. I would like to think my build thread is very in-depth, but it should still only serve as an addition to the FSM. Parts-wise, you'll need complete bottom and top end gasket kits, rings, main and rod bearings. Some people say head studs are optional, but I highly disagree. Replace them as well. Labor-wise, you'll just need a quick hone, and a professional to check clearances for your new bearings. While the block is out, I would definitely recommend having the block hydrosonically cleaned, and replacing your valve stem seals while you're in there.

It could wash it, or it could lean it and cause detonation. Regardless, OP should definitely get the correct ECU - A GSR swap can be fun to drive even with the wrong ECU, but put the correct ECU on it, and suddenly it becomes a LOT more fun to drive.

TomCat39

If it's smoking at idle it sounds more like an all the time sort of thing. Valve seals is typically after idle but idle itself would be fine and smoke free.