AEM Tune to pass emission inspection

[Woody1989]

Hello,

Does anyone have suggestions or an AEM calibration file I can use to allow my 1989 MKIII to pass emissions?

The car does not have a CAT and I'd rather not go to the expense of adding a CAT at this point. Can it be detuned to the point it will pass emissions? I believe the test only requires a 1000RPM and 2000RPM "sniff" to determine PASS or FAIL. So, I can literally limp it across the street to the test facility and have them test it.

Thoughts?

Also, if there is no way to pass without a CAT what CAT is best recommended for a 3" exhaust? Are the Vibrant stainless steel metal core CATs any good?

Thanks,



Brad

 

[John Reed]

Hello,

Does anyone have suggestions or an AEM calibration file I can use to allow my 1989 MKIII to pass emissions?

The car does not have a CAT and I'd rather not go to the expense of adding a CAT at this point. Can it be detuned to the point it will pass emissions? I believe the test only requires a 1000RPM and 2000RPM "sniff" to determine PASS or FAIL. So, I can literally limp it across the street to the test facility and have them test it.

Thoughts?

Also, if there is no way to pass without a CAT what CAT is best recommended for a 3" exhaust? Are the Vibrant stainless steel metal core CATs any good?

Thanks,



Brad

Passing without a cat may be possible, depending on your states emission levels. I have done it before in certain states.

Things to keep in mind. You shouldn't have to "limp" the car around on a fairly clean running map. It should be running smooth, cams and crappy spray pattern injectors will increase your emissions dramatically, and just tune carefully (finding out what you failed on also helps you narrow the tuning down a bit) and you should have it. If you can't even get close with careful tuning, then a catalytic converter will be in order.

 

[Woody1989]

Passing without a cat may be possible, depending on your states emission levels. I have done it before in certain states.

Things to keep in mind. You shouldn't have to "limp" the car around on a fairly clean running map. It should be running smooth, cams and crappy spray pattern injectors will increase your emissions dramatically, and just tune carefully (finding out what you failed on also helps you narrow the tuning down a bit) and you should have it. If you can't even get close with careful tuning, then a catalytic converter will be in order.

Hello John,

The motor is the 7MGTE with HKS cams and a Powerhouse Racing fuel rail with 550cc RC injectors. I do have the test results at the office and will post the results later today.

I've decided against the Vibrant round metal core 3" CAT due to its 5" diameter. The less expensive Vibrant oval ceramic core is an inch or more less thick and is probably an overall better fit underneath.

If there is no way to pass the car without a CAT, are there any other/better high flow CATs I should consider?

Thanks for the reply.



Brad

 

[figgie]

all modern day aftermarket cats flow exceptionally good.

 

[Woody1989]

all modern day aftermarket cats flow exceptionally good.

Hello,

Here is what my results look like. Thanks for any help with tuning suggestions I might be able to make in order to get this car to pass.

Thanks,


Brad

 

[John Reed]

It looks to me you are running a bit rich and also picking up some tiny misfires (may not even really feel). I don't know what your tune looks like, so it is hard for me to say what is left on the table before a cat needs to be put in. Careful air/fuel tuning (again the engine should run GOOD), injector timing tuning and ignition timing tuning will be required. If you feel these are as solid as can be, then you may need a cat. Also plug gap being more open (like stock) helps also.

 

[SupraMan1987]

Appears as if your CO is off the charts. Lean it out, probably running rich. Also appears you have a very slight misfire. I'd say retard the timing slightly as well.

 

[Woody1989]

Appears as if your CO is off the charts. Lean it out, probably running rich. Also appears you have a very slight misfire. I'd say retard the timing slightly as well.

Geesh...how do you and John see a slight misfire with the information I've provided?

So, do you think simply retarding the timing and leaning out the fuel will get the car to pass?

I'm pretty sure I know where/how to retard the ignition, but not so certain about the leaning out the fuel.

Is there a "Tuning your AEM System for Dummies" book I can look into or can I send someone my AEM configuration and ask for it to be changed for me?

Thanks,

Brad

 

[northwestsupra]

a cat is almost pointless on the rolling test, past about 2500 RPMS the cat really cant keep up very well, i would lean it out a little, propane may help you out, while your doing a tune i would get a sniffer "smog analyzer" in the tail pipe and watch your emission levels and it will help you determine if you were getting better or worse. also due to the age of the car the standards for it should be lower than if it were a new car.
i know when i did my last emissions test the car was running very rich due to a slight vac leak and IC pipe leak and a plugged EGR, i had 3 inch pipes and no cat and still passed,but barley. how do you like that powerhose rail by the way lol

 

[northwestsupra]

a cat is almost pointless on the rolling test, past about 2500 RPMS the cat really cant keep up very well, i would lean it out a little, propane may help you out, while your doing a tune i would get a sniffer "smog analyzer" in the tail pipe and watch your emission levels and it will help you determine if you were getting better or worse. also due to the age of the car the standards for it should be lower than if it were a new car.
i know when i did my last emissions test the car was running very rich due to a slight vac leak and IC pipe leak and a plugged EGR, i had 3 inch pipes and no cat and still passed,but barley. how do you like that powerhose rail by the way lol

and sorry this is as close as i could find for things for dummies lol

 

[Woody1989]

a cat is almost pointless on the rolling test, past about 2500 RPMS the cat really cant keep up very well, i would lean it out a little, propane may help you out, while your doing a tune i would get a sniffer "smog analyzer" in the tail pipe and watch your emission levels and it will help you determine if you were getting better or worse. also due to the age of the car the standards for it should be lower than if it were a new car.
i know when i did my last emissions test the car was running very rich due to a slight vac leak and IC pipe leak and a plugged EGR, i had 3 inch pipes and no cat and still passed,but barley. how do you like that powerhose rail by the way lol

Yah, I was hoping the car would be old enough to be exempt from the emissions portion of the inspection, but I'm still five years out on that one!

I didn't know you could find/buy a "sniffer - smog analyzer". I think the inspection shop empathizes with me, but I'm not sure they'll let me tune while it's on their inspection machine. Maybe they will, couldn't hurt to ask.

Yah, don't get me started on Jarrett Humphreys. The more my car is seen by people in the "Supra Circles" the more horror stories I hear about how Jarrett screwed me here or there. Some of it is pretty comical like the time Jarrett told me my car was in New Mexico when in fact a friend of mine saw it at Ross's shop here in Texas. This was before I knew who Ross was or that his shop even existed.

Some of it really isn't comical like the time he ordered a "new" HKS IC setup for me only for it to be the EXACT same HKS intercooler setup I bought for the car back in 1990! Jarrett stuck me with it and kept my $1400. Told me to deal with it or come pick up the car with a trailer as is unfinished. At that point I didn't have any choice but to see that he got the car finished.

BTW, anyone want to buy an almost brand new MKIII HKS Intercooler?!

I've learned that Jarrett is a habitual liar. I guess he can't help it...poor guy. He's a real piece of work, but what comes around goes around. Jarrett will "get his" sooner or later and I won't be shedding any tears for him.

Regarding the Powerhouse fuel rail I can't say if it's good or not as I don't have anything to really compare it to. I do know that I find small pools or puddles of fuel accumulating in-between the intake runners on a regular basis. Not something I'm real pleased with, but Ross and the guys at Dynosaur Performance will be seeing the car again end of this month or first of next. I'm sure they'll find where this fuel is coming from and fix it.

So...you've got me wondering now why you ask about the Powerhouse fuel rail. Are these things known for leaking and burning down cars or something!

Best,


Brad

 

[gaboonviper85]

I woudnt be driveing the car with fuel running out like that!! I personally would stick with the stock rail as it's more than able to flow all the way to 800hp if not more.

 

[figgie]

a cat is almost pointless on the rolling test, past about 2500 RPMS the cat really cant keep up very well

And where pray tell did you pull this gem of information from? Toyota DISAGREES with your assertation.

That is specifically why toyota "tuned" the 7m TCCS to go lean and slightly rich and bounce between both, one side takes care of the NOx, the other side bring HC and CO into line. If it was steady state tune, then you would run into elevated levels of one of the components after a while as the CAT gets saturated.

i would lean it out a little, propane may help you out, while your doing a tune i would get a sniffer "smog analyzer" in the tail pipe and watch your emission levels and it will help you determine if you were getting better or worse. also due to the age of the car the standards for it should be lower than if it were a new car.
i know when i did my last emissions test the car was running very rich due to a slight vac leak and IC pipe leak and a plugged EGR, i had 3 inch pipes and no cat and still passed,but barley. how do you like that powerhose rail by the way lol

A plugged EGR will show as lean not rich. Since now all the air that is supposed to be inert is replaced with atmospheric air. VAC leak will also show as lean as now you are letting unmetered air into the engine which means more O2 then HC. This usually will put the NOx levels at absurdly high levels along with very high CO production.

 

[Woody1989]

And where pray tell did you pull this gem of information from? Toyota DISAGREES with your assertation.

That is specifically why toyota "tuned" the 7m TCCS to go lean and slightly rich and bounce between both, one side takes care of the NOx, the other side bring HC and CO into line. If it was steady state tune, then you would run into elevated levels of one of the components after a while as the CAT gets saturated.







A plugged EGR will show as lean not rich. Since now all the air that is supposed to be inert is replaced with atmospheric air. VAC leak will also show as lean as now you are letting unmetered air into the engine which means more O2 then HC. This usually will put the NOx levels at absurdly high levels along with very high CO production.

This is all great information and I appreciate the input, but what is my next move?

Adjust my fuel and ignition maps down a bit and try again? What's the harm in bringing them way down just to insure I pass the test? Is there a point where bringing them too far down will cause a fail in another portion of the test?

Thanks!

Brad

 

[figgie]

leaning out might work but might make you fail on NOx. That is why it is imperative to have all the OEM stuff. All of it serves a purpose.

 

[John Reed]

This is all great information and I appreciate the input, but what is my next move?

Adjust my fuel and ignition maps down a bit and try again? What's the harm in bringing them way down just to insure I pass the test? Is there a point where bringing them too far down will cause a fail in another portion of the test?

Thanks!

Brad

Lean misfire will cause the HC to go through the roof. Lean will not cause CO to go up (correcting figgies post above). CO goes up when the mixture gets richer.

A catalytic converter works great at 2500 and above, assuming the feed gases are close to correct.

The piss poor spray pattern of most bigger injectors (not sure if you have any or not) and more agressive cam profiles make emissions testing a chore. It really depends on your local regulations, as I said before. You also need to really work on the transients (accel/decel fuel) to keep things clean.

Got your email, I can take a look but going to be a bit tricky without being in the car. Passing emissions with a standalone and some mods can usually be done but takes some work and really knowing what is going on as things relate to each other.

 

[Woody1989]

Lean misfire will cause the HC to go through the roof. Lean will not cause CO to go up (correcting figgies post above). CO goes up when the mixture gets richer.

A catalytic converter works great at 2500 and above, assuming the feed gases are close to correct.

The piss poor spray pattern of most bigger injectors (not sure if you have any or not) and more agressive cam profiles make emissions testing a chore. It really depends on your local regulations, as I said before. You also need to really work on the transients (accel/decel fuel) to keep things clean.

Got your email, I can take a look but going to be a bit tricky without being in the car. Passing emissions with a standalone and some mods can usually be done but takes some work and really knowing what is going on as things relate to each other.

Hello John,

Yes, I have HKS cams and 550cc RC injectors. Now that you mention the transitions between accelerating and decelerating the tune does feel way off in that respect. Not very smooth at all IMO.

I'll see if I can get Chris or George (two different local AEM tuners I know) to sit in the car and see what they find.

Thanks again for your input.

Brad

 

[1jzdarek]

hey i have passed emission test in illinois with with my 1jz on aem ems sound performance said u will never pass emission with aem specialy its a 1j no egr and so far. well i had no choice but to pass it my plates were susspended on my car due to failling emissions so what i did is left not even half a quarter im my fuel tank and put a bottle of rubbing alcohol in the tank i went to the emissions passed with no problems hope this information helps cuz it helped me.

 

[Jostar]

hey i have passed emission test in illinois with with my 1jz on aem ems sound performance said u will never pass emission with aem specialy its a 1j no egr and so far. well i had no choice but to pass it my plates were susspended on my car due to failling emissions so what i did is left not even half a quarter im my fuel tank and put a bottle of rubbing alcohol in the tank i went to the emissions passed with no problems hope this information helps cuz it helped me.

WOW all you had to do was pass the sniffing test, I pass that shit with flying colors, I have a AEM... Why would SP say something real stupid like that??

 

[becauseican]

So what are some ideal numbers for passing emissions testing in regards to timing, rpms and a/f's. 14.7 afr's?. I am trying to get a 1jz JZA70 through, with a Haltech E8 runnig semi seq and waste spark with 550 cc injectors with a stock cat. It failed twice yesterday on the driving and the idle test. Timing is at 15 deg at idle (1000 rpms), and AFR's about 14.2-14.5 at idle, it also failed at 14.7-14.9 afr's idling. The plug gap is at .032 I dont have the sheet here now. I will post my numbers later today.