xblazinlv

Well I attempted to get smogged today, had the original 74k mile cat on it with a functioning air pump.

I failed miserably.....

I'm not sure how to decifer what the results mean, so I attached the test.


My other problem is that the car isn't idling right no matter how we adjust the idle screw, it sometimes will idle at 1500 RPMs or other times goes down to 500-600 RPMs.

When it idles in the normal 720 range, my vacuum reading is only 10-12 which is low I'm assuming. My motor is mildly street ported, but other than that virutally stock besides a downpipe and intake.

xblazinlv

BTW I have brand new plugs, wires, o2 sensor, and all new vacuum lines. I currently have no service engine light codes being thrown either.

rynberg

You have a vacuum leak, you need to fix that first. Also, it looks like your air pump or ACV may not be working properly.

xblazinlv

The air pump is sucking air hard up top, I checked it. I had to hard wire it to a power source because the factory connector wasn't working, but the clutch is engaged and it was functioning during the test.


I must have a vacuum leak, not sure where but I'll have to pull the UIM and find it.

As for the other numbers, they were so bad, I have to have a bad cat too I'm assuming.

I also just replaced the fuel filter...so I know none of the normal components maybe besides the cat converter are the culprate.

mdpalmer

iTrader: (24)

^^ double check your air pipe that connects to the cat converter. Disconnect the tube that hooks to the cat with the exhaust parts cold. Start the engine up and check to see that air is flowing out of the tube. If not, you have to check everything upstream of it (the air pump itself, hoses, and ACV). FYI, I ran my car through a pre-test with a high flow cat, aftermarket downpipe, 3" rear section exhuast, aftermarket intake, new O2 sensor (I don't think it was working properly, since my engine harness was chopped up), new fuel filter, new plugs, "blown" engine, and I had HC readings a little better than yours (@ idle I had about 570 PPM). Your CO2 readings are pretty nuts too. There is a thread somewhere here on theforum that discusses ways to interpret your readings..... if I can find it I'll let you know.

xblazinlv

I actually checked the air pipe yesterday as I just bolted up the exhaust and fixed a leak, it is flowing air into the cat.

If you do find out how to interpret those readings definitely let me know. I'm sure there is a vacuum leak somewhere and that I probably need a new cat, but I was just shocked at how bad those numbers were.

Mahjik

iTrader: (1)

Did you ever check the calibration of the TPS after putting everything back together (since you are having idling problems, it's a good sign something isn't right there)?

Here's how I would start:

1. Check TPS calibration
2. Since you had problems starting and running the car in the beginning, make sure you didn't foul the plugs
3. Check/replace the cat

xblazinlv

I think that is good advice actually....I was going to try in almost that exact order.



Here's another question:

Can you pass smog if you do the vacuum simplification mod where you would block off the EGR and AVC, but keep the stock air pump and cat? I might just do that to get rid of the mess of vacuum lines, less to worry about anyway in terms of leaks.

Mahjik

iTrader: (1)

You'll then have to feed the cat directly from the airpump (if you block the ACV). Whether that will allow you to pass or not, I have no idea. I would recommend getting the stock components working first so you can pass testing. Then start removing stuff afterwards.

misterstyx69

iTrader: (142)

Mahjik has hit this one right out of the park..get a replacement Catalytic..(new cat)..and make sure that the car was taken out for a good run..just before the Emissions test..So the catalytic will be hot and doin it's job....you cant rely on the old catalytic ..Rotary engines have a higher exhaust temp than Piston engines.So they will burn out catalytic converters Faster than "normal"..If you haven't had any problems with your car lately(your compression is good, no Fuel related issues), Then a Regular tune-up and a New cat should be enough to get you to pass.raeding again..street ported engine,,search AIR PUMP TO CAT..EMISSIONS,FAILED EMISSIONS..stuff along those lines ..there should be info on how to hook your air pump directly to the cat..via the SPLIT AIR TUBE..and the New Catalytic should provide for attaching a tube to it..best of luck

xblazinlv

Yea.... I'm going to do that. Guess I have to start taking it apart and try to find my vacuum leak.

Is there anyway I can test the ACV and EGR valve to ensure they are working properly? Also, if my TPS is off, would that basically kill my smog as well?

I'm thinking I need a new cat converter with those high numbers, but I want to get this other stuff straightened out first. Thanks for your help

sevensix

iTrader: (1)

your vacuum should be around 20-22 in Hg at idle ~700-1000 rpm from what i remember. if your idle is higher then vacuum should also be a bit higher.

mdpalmer

iTrader: (24)

From what I've seen before, I think it should be around 18 inHg @ 750 RPM (randomly grabbed this from pg. F-220 of 1993 FSM). My motor was street ported and had shitty compression and had to idle at 1000 RPM to keep the shakes at bay (vacuum was 12-14 inHg).

xblazinlv

When my motor idles at or above 1000 RPMs, my vacuum is around 14-16

zerrovalve

xblazinlv man that's alot fuel, 10% c0 would be gross polluter here in the state of CA you should check all of the above and also maybe your ect for close loop operation

xblazinlv

ECT???

I really think I've got a bad cat, and obviously a few other problems

I'll get it figured out, there are only so many components that would cause this problem.

Everything else is brand new, so I don't have to worry about that stuff (fuel filter, plugs, wires, oil, filter, etc)

sevensix

iTrader: (1)

is this cold or hot figure? i assume hot?

zerrovalve

Engine Coolant Temp sensor, well i don't think a cat will oxidize 10% of co and a cat is designe to work best at around 14.7:1 a/f meaning when your car is in fuel control for emission only. and 10% of co means that you have an extremely rich mixture, so what ever that can cause your car to run rich is what you should look at like your load sensors (map, tps) and your ect which tells the pcm that normal operating temperature is up so it controls fuel unless you have a performance pcm that doesn't care about emission then yeah it would not need to be checked out i guess... you also mention a down pipe does that mean your primary cat is gone?

mdpalmer

iTrader: (24)

Not sure. The section I grabbed this from was relating to troubleshooting: "engine rough, on deceleration". I assume that the vacuum is checked at standard idle speed and a warm engine....

xblazinlv

I'll have to check on the ECT..... that could be a problem as well. I'm sure I need to re-calibrate my TPS as well. Lot's to do....

xblazinlv

Where is the engine coolant temp sensor? Does it have anything to do with the stock gauge functioning? My stock coolant temp gauge works if that helps at all. I couldn't tell the location by looking in the FSM.

Is it on the back of the water pump?

Mahjik

iTrader: (1)

The Coolant Thermosensor is on the back of the waterpump housing along with the Thermoswitch. That is not the same sensor which is for the dash gauge.

xblazinlv

Gotcha.... I'm going to have to replace that. I looked at it and the wire looks horrible and I was able to pull it out of the back of the sensor. There's one problem