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-   -   Failed Emmisions test, WA (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/failed-emmisions-test-wa-715949/)

dhays 12-26-07 02:23 PM

Failed Emmisions test, WA
 
I actually am not surprised that I didn't pass. In WA we can get a free retestI've read through the FAQ and run a search but still have questions.

Washington makes an older car do both an idle as well as a 25mph test. I failed today with my new '94 FD. AFAIK, the car has a Bonez downpipe and high-flow cat. It has a Greddy Airinx intake system. 57k original miles.

I barely passed the 25mph HC test. I needed to be under 150 ppm and I tested at 145 ppm. I failed in the idle test. I needed to be under 220 ppm HC and 1.2% CO. Instead I was at 478 ppm and 4.68% respectively.

I had driven the car for over a 1/2 hour before the test with much of that at 3000 rpm or better on the highway. It is cold today but the coolant temp was about 190F.

Here are my ideas from my own limited knowledge and am looking for more. First of all, the oil and filter need to be changed as I'm a couple hundred miles short of 3k since the oil change I had done when I bought the car less than a week ago. I'm assuming that it could use new plugs since I don't know when they were changed last. I also don't know when the fuel filter was changed so I would like that done as well.

I frankly don't understand the mechanics of the car well enough to speak intelligently with a rotary mechanic. Any ideas as to what else should be checked or what else might be a likely culprit? FWIW, I am wondering if I don't have some ground problems with the car as well. Could a poor ground contribute as well?

BigWillieStyles 12-26-07 02:28 PM

well take the high flow cat off for a start.

I was under the impression it might be possible to raise the idle rpm just for the test, this will give a cleaner result

dhays 12-26-07 02:32 PM


Originally Posted by BigWillieStyles (Post 7665889)
well take the high flow cat off for a start.

I was under the impression it might be possible to raise the idle rpm just for the test, this will give a cleaner result

I'd really like to avoid taking off the high flow cat. One simple reason is that I don't have anything to replace it with. I've noted that other FD owners have passed even CA emission testing with that high-flow cat. So rather than the first thing to do, I'd much rather make that a "last resort" solution.

I thought about idle speed. During the test the idle was a bit low, under 600 rpm. Even if I increased the idle a bit, I doubt that it would help enough since I'm even close on the 25mph test in HC.

bryant 12-26-07 05:39 PM

have you checked threw your egr system?

dhays 12-26-07 06:07 PM


Originally Posted by bryant (Post 7666471)
have you checked threw your egr system?

Nope. Keep in mind that I'm about as ignorant as they come. I will start to read through the shop manual and see what i can learn about the egr system. Thanks for the suggestion.

I made an appointment for the car at Jerry's Small Car Shop for the 4th. They are WA State Emission certified as well as having a great rep as a rotary shop. I am going to put myself at their mercy since really the only thing I know about rotaries is that they go around instead of up and down.:lol: Jerry did mention that failing at idle (especially failing badly as I did) is NOT a good sign. Since the HC were so high at idle I'm assuming that it is running way too rich at idle. Not sure what could cause that.

4CN A1R 12-26-07 07:20 PM

+1 on the egr. i'd make a bet you have some complication there.

or move to florida, that'll also solve your problem

darkside7 12-26-07 07:24 PM

make sure your airpump is working.

bryant 12-26-07 08:04 PM


Originally Posted by darkside7 (Post 7666788)
make sure your airpump is working.

nice^^

dhays 12-26-07 08:19 PM


Originally Posted by darkside7 (Post 7666788)
make sure your airpump is working.

OK. (As soon as I can find it that is.)

I do recall reading a thread on how to check if the airpump is working somewhere. I'll see if I can find it.

2FAST7S 12-26-07 10:09 PM


Originally Posted by bryant (Post 7666471)
have you checked threw your egr system?

sorry, egr has nothing to do with HC or CO...egr is only used to lower NOx.

The problem with your FD is more of a rich idle...you have too much unburned fuel going through the highflow. You need to lean out the idle or possibly find a way to inject air into the cat(like the stock system with the acv/air pump setup).

I would clean out the air filter, get a set of fresh plugs/wires and maybe even try a slightly higher idle rpm (lean it out - stand alone ecu option only).
You might pass with the little tune up though!

dhays 12-26-07 10:42 PM


Originally Posted by 2FAST7S (Post 7667357)
sorry, egr has nothing to do with HC or CO...egr is only used to lower NOx.

The problem with your FD is more of a rich idle...you have too much unburned fuel going through the highflow. You need to lean out the idle or possibly find a way to inject air into the cat(like the stock system with the acv/air pump setup).

I would clean out the air filter, get a set of fresh plugs/wires and maybe even try a slightly higher idle rpm (lean it out - stand alone ecu option only).
You might pass with the little tune up though!

Thanks for the info. I keep learning lots and also finding more that I need to learn.

Speed of light 12-27-07 02:00 PM


Originally Posted by 2FAST7S (Post 7667357)
sorry, egr has nothing to do with HC or CO...egr is only used to lower NOx.

The problem with your FD is more of a rich idle...you have too much unburned fuel going through the highflow. You need to lean out the idle or possibly find a way to inject air into the cat(like the stock system with the acv/air pump setup).

I would clean out the air filter, get a set of fresh plugs/wires and maybe even try a slightly higher idle rpm (lean it out - stand alone ecu option only).
You might pass with the little tune up though!

+1

You can raise the idle to spec easily and properly by adjusting the idle air bleed located under the intake elbow flange. This will have the effect of leaning the mixture slightly since no additional fuel will be added.

dhays 12-27-07 02:09 PM


Originally Posted by Speed of light (Post 7669254)
+1

You can raise the idle to spec easily and properly by adjusting the idle air bleed located under the intake elbow flange. This will have the effect of leaning the mixture slightly since no additional fuel will be added.

Thanks Speed. Something else for me to look up in the shop manual. I sure appreciate all the suggestions and basic info on the car.

Six Rotors 12-27-07 02:31 PM

Note high HC can be the result of poor spark plugs,hence incomplete combustion.High CO is usually the result of rich mixture.

Upgrayedd 12-27-07 02:40 PM

With how close you are, compared to my terrible results, you may want to try a little denatured alcohol in your gas for the retest as well as fresh plugs. It's very common for people to fail the first time around ;) I tried 4 times and gave up :icon_tdow I have a stock cat in my garage if you decide you'd like to hook it up and make sure the airpump is giving air to the cat, if in fact it has not been removed. Jerry is a good choice. He'll be able to help you out for sure, and if all is well he may even give you a waiver ;) Lord knows I could use one of those

dhays 12-27-07 03:44 PM


Originally Posted by mazdatim (Post 7669391)
With how close you are, compared to my terrible results, you may want to try a little denatured alcohol in your gas for the retest as well as fresh plugs. It's very common for people to fail the first time around ;) I tried 4 times and gave up :icon_tdow I have a stock cat in my garage if you decide you'd like to hook it up and make sure the airpump is giving air to the cat, if in fact it has not been removed. Jerry is a good choice. He'll be able to help you out for sure, and if all is well he may even give you a waiver ;) Lord knows I could use one of those

One of the reasons I chose him, besides good reviews and a positive referral from Atkins, is the fact that he is a certified emission shop so I can use any work he does to get a waiver. I was also looking at Import Auto Repair in Tumwater since with traffic they might be quicker, but they are a certified emissions shop.

Anyway, I've spent all afternoon reading through the shop manual and end up with even more questions than I had when I started.:confused: I'm looking forward to next Friday when I can take the care into see Jerry. If nothing else, I'd like to see how they reach all the spark plugs.


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