Attacahed is my smog sheet for my car. Its a low milege collectors item, and i have put maybe 2k miles on it since i got it 2 years ago, and it had new plugs and wires then. I got the california regeristration in the mail saying in needed to complete a smog check, so i drove it around for a good week, revving it up nicely and getting a fresh tank of gas in it, and it failed. If anyone knows first, what tune up methods do i need to do to this car, (i am very familar with the 3.0L m3 engine but not this one), and second, what the numbers correspond to, (i remember when i didnt pass in my 95 it was due to the 02 sensor and it wasnt passing at low rpms). The car runs a little rough on the idle, until it gets nice a warm, but nothing significant. Are there any valve adjustments that need to be done? Any help is greatly appreciated. Thanks

-Nick

Well, you can go back to where you got it smogged and ask for (I'm not sure on the name of it) a certain form, where the state of California will pay for something along the lines of 75% of what it costs to get your car fixed to where it will pass smog. Just a heads up.

Maybe a bad cat or O2 sensor? A few posts in s14.net suggest that a new cat solves all the smog issues. But I'd check all other emission components first.

I'll be taking my newly acquired E30 M3 to smog next week. Keeping my fingers crossed :paranoid:

thanks, good luck with your m3 as well. One thing ive learned is that its worth it to find the problem than than do a quick fix. I can get a new cat, and it will pass, but in 2 years after running rich, all the catalyst will be burnt out again, and I dont want to shell out 400 dollars every two years for smog. Im replacing o2 sensor, checking vaccume lines, replacing fuel regulator, etc, and hopefully that fixes the problem or gets it down far enough where i feel comfortable in putting a new cat on.

-Nick

You have a intake gasket leak.. you need to replace these following items..
intake "big rubber block gaskets" (2) blue ecm temp sensor, cap & rotor, spark plugs, and a wire set if it's the orignal one's also replace the 02 sensor since your at it..
And run the heck out of the car before you smog it to burn all the carbon out of it.. and she'll pass... :)

BTW here's a good site, where all of us e30 m3's hang out www.s14.net alot of support and help...

well i pulled the plugs, they have slight carbon buildup on them, nothing that would prevent them from failing, but enough to signs that its not running right. I have gotten carb cleaner, and sprayed all around the intake manifold and vaccume lines to see if there is leakage, but no sign of the carb cleaner getting inside, meaning no vaccume leak. I am assuming maybe MAF went bad, or another sensor, so thats the next check. Any suggestions?

You're running super rich. A vacuum leak will lean mixtures on L-jet systems, unless misfiring. You need to check for high fuel pressure, leaking injectors, O2 sensor readings, coolant temp sensor specs, MAF specs.

Yeah, I agree with the fellow about changing those parts, and driving it hard. SInce you are located in California, choose a really hot day, go somewhere where there are no cops, and drive it really hard. I mean hit about 120 mph, and stay there for a good 10 to 15 minutes-the more the marrier. I had an E36 M3 with complete engine modification: Dinan supercharger, Dinan intake, Supersprint headers, Shrick cams, Supersprint exhaust, and I was afraid for it not to pass smog. I live in Southern california, so I choose a hot day to get it smoged, and I drove about 110 to 120 mph for a good 15 to 25 minutes. Then I went to the smog station, I got out;however, I left the car on. I went in and gave all of my information, and then went back inside the car I kept on revving the engine up, and sometimes I will leave it revved up at 5000 rpm. It passed with ease.GOod luck to you

First off, always pay extra for a preliminary smog check. If you flunk the CA smog test bad enough, your car will be flagged as a "gross polluter", and you may have to bring it to a referee.

If your is in good shape, tuning ,cat etc, then go to the drugstore and buy 2 or 3 bottles of isopropyl alchol, with the highest percentage you can find. Longs sells like 99% (1% water), try not to use rubbing alcohol because it is only 70%.

I have many sketchy performance cars that barely pass (or barely don't pass) and this alcohol trick works every time so far.

I usually have about a quarter tank of gas, and put in 2 bottles, and then after _passing_ the smog test, I go fill up the car to dilute the alcohol.

YMMV

Jay

that you call Bill Arnold, the E30 M3 guru in San Rafael. Pretty close to Napa and he knows his stuff.

If you need to replace the cats, there are some decent aftermarket center sections with cats available. I found a used center section and a Supersprint muffler for $400 a few years back.

And yes, having your car hot for the smog test and blowing out all of the carbon is a good idea. Good luck!

Bill

First off, always pay extra for a preliminary smog check. If you flunk the CA smog test bad enough, your car will be flagged as a "gross polluter", and you may have to bring it to a referee.

If your is in good shape, tuning ,cat etc, then go to the drugstore and buy 2 or 3 bottles of isopropyl alchol, with the highest percentage you can find. Longs sells like 99% (1% water), try not to use rubbing alcohol because it is only 70%.

I have many sketchy performance cars that barely pass (or barely don't pass) and this alcohol trick works every time so far.

I usually have about a quarter tank of gas, and put in 2 bottles, and then after _passing_ the smog test, I go fill up the car to dilute the alcohol.

YMMV

Jay

why not just use ethanol or methanol? Or ideally get your hands on some methyl t-butyl ether. Oh wait, these things aren't easy to get.

Years ago i had the same problem, change the cat on it passed with flying colors. Now ijust have a resonater so ever 2 years i swap my resonater to my cat, and i pass with flying colors.

Attacahed is my smog sheet for my car. Its a low milege collectors item, and i have put maybe 2k miles on it since i got it 2 years

I noticed 2k in 2 years. When was the last time you changed the oil? High hydrocarbons can be linked to stale/dirty oil.

Years ago i had the same problem, change the cat on it passed with flying colors. Now ijust have a resonater so ever 2 years i swap my resonater to my cat, and i pass with flying colors.
Not to be a jerk, but if you put a new cat on anything, the car will pass with flying colors. It's not really fixing the problem, though.

And run the heck out of the car before you smog it to burn all the carbon out of it.. and she'll pass... :)


What he said. Seriously drive it like you stole it for 20 minutes right before you take it in...

well i pulled the plugs, they have slight carbon buildup on them, nothing that would prevent them from failing, but enough to signs that its not running right. I have gotten carb cleaner, and sprayed all around the intake manifold and vaccume lines to see if there is leakage, but no sign of the carb cleaner getting inside, meaning no vaccume leak. I am assuming maybe MAF went bad, or another sensor, so thats the next check. Any suggestions?

Ok you have both CO2 and O2 that means that the cats aren’t working so maybe they were not hot yet. So that is one problem and you have a rough idle and you said you had carbon buildup so you might try top engine cleaner to clean it out and the injector. You say that you only put on 2k in 2 years if you only drive it short trips like 15 to 20 minutes at a time it doesn’t get that hot carbon builds up so you can go for a long drive like 2 hours non stop and it will actually clean it out.

By the way good choice NOT replace the cats. People that do, will replace them in two years again because they really did not FIX the problem they just put a really expensive bandage on it and the real problem is the car not running right and that will destroy the cats.:handclap

Thanks for all the help guys, I have an update. I replaced the engine temp sensor and O2 sensor in hopes that the readings were off. Of course I think the 02 sensor has never been changed, and it ran slightly better once replaced.
I started the car, drove it down to the office and planned to take it into the referee to have it checked out. When I got back in the car the damn thing wouldnt start, the starter wasnt engaging. So i push started it and got it back to the house, and started pulling the top end of the intake off to get to the starter.
One thing that caught me off guard was the fact that the hose that drains from the bottom of the Air intake manifold (big black box before the throttle boddies) had a hose comming out of the bottom, similar to my 95, but the hose appeared to be cracked (i dont believe i cracked it when removing it from the box). After that was removed, there were 4 individual throttle bodies one for each cylinder, however i noticed definate oil in the intake. When i opened the throttle boddies and ran my finger in the intake valves there was definate oil in there. Now at this point in the intake i know that each cylendar is isolated by its own intake rail basically, so how the hell could it be getting oil in all of the intakes? I was told that because there is a crack in that one hose, that it could be throwing the timing off and getting blow by, but how the hell could oil be in blow by, the top of the cylendar is suppose to be clean. Any advice on this would be greatly appreciated.

-Nick

Believe it or not but there is a hose that goes from your valve cover to the intake that is suppose to vent blow by in to the intake to go back in to the cinders this could be one way that oil is getting in to the intake as normally a little oil will get in to the intake.

so then a definate problem i would assume would be that there was a crack in the blow by hose, which in turn was an intake leak and gave it a faulty reading. Excellent, I will replace that and then take it in. Any other advice?

-Nick

so then a definate problem i would assume would be that there was a crack in the blow by hose, which in turn was an intake leak and gave it a faulty reading. Excellent, I will replace that and then take it in. Any other advice?

-Nick

Make sure you have good gas in the car for the test it would be a good idea to put premium gas in and don’t forget that for the cats to work they have to be hot. Oh and good luck.

NEW NEWS!!!! The car finally passed, I got a new o2 sensor in it, a new temp sensor, and a new blow by hose. Thanks for all the help guys, all good suggestions.

OK some new news. Because I am down in Santa Barbara, I am having someone take care of my car up north, taking it in and such. I changed out the o2 sensor and hose and engine temp sensor myself. Anyway I just got the good news that it passed, but it turns out that i just got a $250 bill. Not too bad, i know smog is like $70 of that but I guess the car was "diagnosed" and the fuel mixture was turned up too high. Is there a fuel mixture regulator on this car or anthing that would change that??? I know there is a fuel line regulator, but that was not touched. He said he changed a setting and asked if anyone had touched it. Any info on if this is possible would be helpful, I dont want to get screwed by some guy making shit up.

There is a "Fuel Quality Switch" inside the engine computer (DME). You can access it by prying off the small plastic plug on the outside of the case. Use a jeweler's screwdriver and carefully turn it all the way COUNTER-clockwise. This is the '0' position, and where it should run. Nowhere in any documentation does BMW or Bosch allow you to change that switch setting. But if you have poor quality fuel, it can increase or decrease fuel and cut back on the ignition timing. Jim Conforti used to have a link up, but search some of the archives on various E30 M3 sources, and you'll find out what the switch settings do.