bdpratt

I was having problems passing smog because my 85 GSL-SE was running too rich. A friend who does not have experience with rotarys (but does with emmisions) made adjustments and now it passes fine, however it idles rough.

He had to adjust a screw inside the air flow meter body. (Not the screw on the outside). He had to remove the air filter box, pry open the meter housing and turn a screw that made a click noise as it turned. He turned it three clicks. He said it was a rough adjustment for the meter. (Not the fine adjustment found outside the housing.)

I would now like to fix the idle and I have the article by David Lane, but it does not mention this "rough" adjustment in the meter housing. I am concerned that I will need to richen it up using this adjustment. Can anyone tell me how it works and how I can find the proper setting? My friend just turned it until the HC levels went down so it would pass smog, but it is not nessassary the optimum setting.

Thanks,
Ben

MyRxBad

Rotaries are supposed to run rich... How was the car idling before? If it was fine, then readjust the air flow meter (3 clicks) back to what it was.

j9fd3s

iTrader: (3)

there is a spring for the flapper door, it is adjustable for tension. you need to put it back into the stock spot, i have tried 4-5 clicks both ways on the afm and the best setting is the stock one.

mike

bdpratt

thanks, i'll put it back where it was.

bdpratt

I have the airflow meter off and apart, but I can't find what was adjusted. What do I turn that made a clicking noise, and which way to I turn it to richen it up?

Thanks

bdpratt

Ok, I think the adjustment is the teeth in the gear, so I have moved it three theeth clockwise, but I have another question.

I measure the resistance between Vs - E2. I think this should indicate how open the gate is. Fully closed the ohms are about 200. When I start to open the gate, the ohms go to 500 and stay about there though the whole swing. Then at fully open, it drops back to about 250. Is that right? It doesn't seem right to me. I would think that it should increase linearly to 1000 ohms as I open the gate. Does anyone know?

Thanks

j9fd3s

iTrader: (3)

yeah, you need to measure the voltage at the ecu to get the right readings. i dont really know the theory, but it has to have the full 12v going thru it to give the right reading

mike

FJ

Sorry, I don't have the answer, but it doesn't seem right to me, either..

Vs-E2 should, indeed, increase linearly with the flap opening, according to the diagram. As diagrams (and logic) can be misleading, I checked mine.

Had 100 ohms when closed, and it increased to 500, linearly. When fully open, it did drop to 250 as yours did. I was surprised also, as there is no switch mentioned in the manual that would activate only when the flap is fully open. Mine has been running well, so it has to be normal.

As with j9fd3s, I don't know the theory either (as much as I would like to). The information is simply not available, as far as I've found.
I suspect the actual ohm values are not important; the ECU takes a peek at the voltage at idle and at higher Rpm's. It uses relative values, not absolute. Same reason some cars run badly when the battery has been disconnected for a bit: it takes the computer a little time to "re-learn". But I've not found that to be the case with mine.

The fact that it goes to 500 ohms as soon as you move the flap sounds like a problem, but I'm not sure what to suggest... Sorry I couldn't be of more help...

-John

P.S. : The AFM is not meant to be adjusted. Don't screw with the factory settings. Find the real problem or you are chasing your tail.

bdpratt

Thanks for having a look at yours for me. I definetly think there is something wrong with my AFM. Everything I have found on the Web indicates the ohms should start at 20 and linearly increase to 1000 as the gate is opened. Maybe this is the source of my smog difficulties.

Thanks again.

While I'm thinking about it, I have one other question.

The device mounted next to the firewall on the passenger side with a vacuum tube and a cable running to the throttle, located directly above the Vacuum Switch. What is it?

The T coupling that connects the vacuum lines to this device was broken. I have replaced the coupling, but I don't know what the device does. Possibly Cruise Control? Thanks.

Ben

j9fd3s

iTrader: (3)

its about 2" around? vcauum line and 2-4(i forget how many) wires? thats the reason it doesnt pass smog. i have no idea what else that valve does, except make the car fail smog.

if you want the afm voltages at ilde, wot and cruise i have them

mike

j9fd3s

iTrader: (3)

its about 2" around? vcauum line and 2-4(i forget how many) wires? thats the reason it doesnt pass smog. i have no idea what else that valve does, except make the car fail smog.

if you want the afm voltages at ilde, wot and cruise i have them

mike

bdpratt

I'd apprieciate that

Ben

Mark S

iTrader: (1)

I'm about to take my car in for it's first emmissions test

Would anyone mind describing in more detail how to adjust the AFM to change the mixture?

bdpratt

I give you my recent experience in getting my '85 GSL-SE smogged in CA.

1. First I did not get a pre-test. This was my first mistake. The HC and CO were around 900, which is about three times the gross polluter levels. Because I did not get a pre-test, the DMV was immediatly notified, which meant I had to get re-tested at a test only shop. Test-only shops do not give any help in finding the problem, they only pass or fail you.

2. The main catylitic converter (the last one) was rattling. So I got it replaced. This cost $225. I then got it retested. Keep in mind, each re-test costs $40 bucks. It still failed. The emmission levels were about 700.

3. I then took it to a friend that know emmissions, but not rotaries. We hooked it up to his machine and adjusted the Idle Mixture with the L--R label and also the mixture setting directly on the AFM. Both of these we put as lean a possible (CCW). Then turned up the idle screw cause it was idling bad. It passed ok on his machine. (But I had to take it to the Test-Only for the real test)

4. I drove 4 miles to the test only. It failed. The levels were about 600. (They were 120 at my friends shop).

5. Took it back to friends shop. Levels were 600. Played with the Idle Mixture screws again. Emmisions back down to 100. Drove to the test-only.

6. Failed again. Levels about 600. It was like the rich/lean mixture was being reset by the computer after a few minutes.

7. Decided to try something else cause I was getting nowhere (and desperate). So I replaced the other two catylitic converters as well. They were $170 each.

8. Went back to test only. The two new cats made no difference. Still about 600. (That really sucked!)

9. So I went back to my friends shop. We took the AFM off. On top is a black plastic cover. Pry the cover off and inside large black plastic gear. He thought fooling with that gear might help. (I don't really know what it does, but its like a course rich/lean adjustment.) When turned it 3 notches clockwise. Guess what! The HC and CO was less than ten. The car also felt more responsive, but idled really bad.

10. I drove it so the test-only guy. He gave me a weird look about the idle, but I think felt sorry for me at this point. He tested the car and it passed like a champ! 6 HCs and 17 COs at 15mph. I little higher at 25mph. Well I got my certificate and got registered.

Lessons learned (the hard way):
At least two of the cats were a waste of money.
Get a pre-test! Test-Only sucks.
A lean mixture is the way to go.

Since then, I had to put AFM mixture back to normal, because I never could get the idle right with it that lean.

Anyway, if you need any more specific info, let me know. Good luck!

Ben

MyRxBad

Yes, Cruise control.

Mark S

iTrader: (1)

Thanks very much, Ben. It sucks that it took you 6 tries to pass... I have definitly heard some sad stories when it comes to passing CA emmissions, though

j9fd3s

iTrader: (3)

the air pump/ air control valve are key to passing the smog test

mike

bdpratt

Can you detail what you mean by this? I have followed the steps detailed in "Secondary Air Control System" of the shop manual and the ACV and related devices all check out. Also the air pump is working.

Do you know of any other specific tests or things to look for regarding the ACV?

Ben

yety1

Regarding your question about the "device mounted on the firewal" is called the actuator and is part of the Cruise Control System the cable hold the throttle and is assisted by vaccum. so If you have already replaced the T connector you may be all right. unless the diaphragm (inside of the actuator's body) is toasted or broken... good luck