'93 civic failed emission or suspicious emision test ?

"robb" wrote in news:8L- dnY2qKZjT0rzXnZ2dnUVZ snipped-for-privacy@earthlink.com:

It is NOT "standard practice". You replace the sensor once it stops behaving as it should.

You're way high on HC and NOx on both years' tests, but the '09 CO of over

9% may be just a one-time glitch. It could simply be that the cat was insufficiently warmed up for both tests.

You don't have EGR, so that won't be an issue. Have you ever checked the basic ignition timing? How old are your plug wires/cap/rotor/plugs?

Don't know. In my area you can have it tested any number of times until it passes. I think you have to pay for each retest.

If you randomly replace parts with no success you'll be out at least that amount anyway.

First thing to do is re-book the test, but at a different station. Make sure you're the very first car on the machine for that day. Take the car for a long drive (at least an hour) and time your arrival at the station with just enough time to hand in your key. TURN THE ENGINE OFF; DO NOT ALLOW IT TO IDLE. They should have the vehicle on the dyno within fifteen minutes at the outside. This will ensure the cat is up to temp and as efficient as it can be, which is critical.

IF the car fails again, even when properly prepped, THEN you start doing troubleshooting. The results from this test, combined with the results from the other tests, should be enough for a competent tech to daignose the car.

Reply to
Tegger
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please, if your reading age drops below 3rd grade, it's best you do.

Reply to
jim beam

Well, it was stated that the tester was having a hard time positioning the machine's tach pickup... and 2700 is suspiciously close to 1/2 of

5000 (maybe the car's tach was actually reading 5400). IF the tach pickup was only getting every other spark (like from only one coil of a 2-coil pack on a 4-cylinder) then it could easily read 1/2 the correct value.

Get it tested again somewhere else- that'll give you a final answer.

Reply to
Steve

C'mon, Jim....

Its a CHEAP test, and there's certainly reason to question the first test (yes you CAN screw it up... its not easy, but it can be done, and I mentioned one way- getting the tach pickup positioned incorrectly so that its off by a factor of 2).

If this were an OBD-II system resetting a code repeatedly, I'd agree with you 100%, just fix the problem. But it WAS a suspect test procedure.

Reply to
Steve

that's the worst thing about the op's description of the test - the tach reading, unless it's a obdII vehicle, is taken by putting a sensor on one of the plug leads, under the hood, not a "paddle" on the dash. and revving the engine is perfectly kosher if the cat is cold or there is a misfire.

bottom line, the test was good. the op's description was unreliable. and his paranoia unjustified. the emissions result was perfectly consistent with the failure that followed.

Reply to
jim beam

very hard to mess it up. and you won't get a "factor of 2" on this vehicle.

the test is kosher. the op's description is flawed. spending more money on a test would have been a waste.

Reply to
jim beam

Actually, I've seen OBD-1 inspections done on machines where a mag-mount antenna is stuck to the underside of the hood or fenderwell near the engine, not on a plug lead. Not all machines are made the same, and I immediately thought that design was just begging for a frequency error- crappy machine design if you ask me. But even clamping on a plug wire can have an error. I have used enough induction-pickup timing lights that get enough cross-talk between plug wires that they sometimes fire multiple times per distributor rotation, unless you position the pickup

*very* carefully. And with a single antenna system like I described, you can get exactly the opposite problem on waste-spark ignition systems. The machine expects to pick up all spark pulses and divide by 4, but if it only picks up the spark from 1 coil and divides by 4, it will get 1/2 the correct RPM.

and

If the description was so poor, then you have no stronger case that it was good than I have in saying that it is questionable.

Some aspects were, I'll give you that. He admitted he wasn't paying close attention. But if he *EVER* saw 6000 on the car's tach, that alone make me suspicious. 3500 RPM or so- sure. 6000? No WAY.

MAYBE.

$30 for another test will remove all doubt. Cheap. If my wife came home with the same story, I'd take it myself and have it tested before I started throwing money at emissions parts.

Reply to
Steve

Maybe. Those cars can be sensitive to test procedures. I always let them run @ 2500 for 3 or 4 minutes before testing, I had a much easier time getting them to pass that way.

I hate to sound nebulous, but... maybe.. O2, map, coolant sensor, tight valves.. there possibilities are almost endless.

Er.. um.. maybe ;) Yes, I have seen plenty of O2's last a long time. As another poster suggested, it's time to get your car someplace

*competent* Ask your friends, call the BBB, call AAA.. find someone with a track record of 'very high quality'. Dont shotgun it with cheap parts, it may work, probably wont. At least 3/4's of the problems I see mentioned on this board stem from someone trying to save money.... Good luck, and I hope this helps. Ben
Reply to
ben91932

The original was of super high quality if it lasted over 200,000 miles. Why even try another brand? From my experience, denso's, bosch etc are all a crap shoot. If you install it and it doesnt work your only recourse is to exchange it and try another piece of crap and cross your fingers. Maybe they'll refund your money.. maybe not. If you value your time as I do, only use good parts, and never as a guess. HTH, Ben

Reply to
ben91932

What happen, what i did and PASS results follow.

First emmisions test failed. Tester had a difficult time geting a stable tach reading. Car died while driving two days later, would not re-start, or fire. Car had a very weak spark (as tested with my hand). Tested coil with Ohm meter at ~ 8 kOhms it was in replace range.

I replaced ignition coil, replaced plug wires, I cleaned the rotor and cap terminals, I changed the plugs, replaced the PCV valve and put in a new engine air filter. Then i took for my free retest.

2009 **( RE-TEST )** numbers =========================== ....................25/25 test............50/15 --------------------------...........--------- HC ppm .........60....................54 CO %.............0.13 .................0.15 NOx ppm.......168...................146 RPM..............2084.................1913 CO + CO2 %....15.1...............15.1

So not too bad Thanks to groups for helping.

robb

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Reply to
robb

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