Smog question? CA

[///Bimmerfan]

Okay today I went to take a pre-test to see if my 86 BMW 325es would pass and it ended up failing due to the CO the max you can have is 0.63 and I got 0.71 so does anyone know what I could do to fix this, any suggestions???

Thanks

[///Bimmerfan]

bump

[jlevie]

Were HC and NOx also high, even though they passed? If so I'd suspect the catalytic converter.

[///Bimmerfan]

Here are the official numbers.

[///Bimmerfan]

sorry for bump but I need help

[jlevie]

I'd say it is time for an catalytic converter

[///Bimmerfan]

So it wouldn't be the o2 sensor? Just the cat

[george graves]

What did you do to prepare for the test?

[///Bimmerfan]

What did you do to prepare for the test?

I changed the air filter, changed the oil, but I didnt change the sparkplugs and the cap and rotor. I didn't change the spark plugs because they were already bosch platiums in it.

[george graves]

Bosch Platinums suck IMHO. There is not enough surface area of something. The stock bosch plugs you get from the dealer are better.

Can you afford to do one more pre-check?

Here is what I would do.

Get 2 cans of sea-foam - run one in your tank when it's almost empty. The other, suck into a vacuum line, 1/3 of the can at a time, shutting the motor off for 30 mins in between. Then go drive the living piss out of it. You should produce a Hindenburg sized cloud of smoke if done correctly.

Pull your cap and rotor, and clean off any black with the flat of a screw driver.

Swap out those plugs for some from the dealer - make sure they are gapp'ed correctly..

Fill up on 91 chevron - and before you pull up to the smog station, again, drive the living piss out of it (a steep hill works well for this) - you want the cat smoldering hot when they hook you up.

That's what I've done in the past and it's worked for me every time.

HTH

[Farbin Kaiber]

x2 on everything above. Your car is designed for Bosch plugs, but not for Platinum ones.

[///Bimmerfan]

okay, But I wan't to fix the smog problem not get around it!

[Farbin Kaiber]

These methods are the proper ones for "fixing the problem". Install stock plugs, clean distributor rotor/cap, run 91 octane, seafoam the engine, and give the catalyst ample time to heat up for efficient conversion of emissions.

[deutschman]

yeah all the things mr. graves told you to do are right on. i am doing the same thing right now with my '87 325e. i got a new cat, new plugs, new oil filter, new fuel filter, and cleaned off my cap and rotor. i am hoping my 02 censor is still good because i don't have the $ for a new one, and my air filter still looks good. make sure your cat is really hot when you go for the test!!! if you have to wait for the tech to do the smog keep the car running till he does the test.

[Jon325i]

Ok - thread revival time. I've been searching around here today and this particular thread seems to be the most relavant to my issue. Come early June 2010, I have to get my car smogged and I am having concerns about whether it will pass. In the last two attempts, it has barely squeaked by as far as the HC (hydrocarbons) count is concerned during the 15mph runs. Listed below are the results from my tests in June 2006 and June 2008. Below the test results I brokedown the notable "prep work" I performed prior to each respective test.

Car: 1991 BMW 325i, 5-speed

Test date: 06/06/06

Odometer: 174,836
Vehicle condition/setup: unmodified M20B25, 4.10 LSD, 15x7s w/ 225/50 tires

Results 15mph (2063 rpm):
HC: Max = 108, Ave = 31, Meas = 104
CO: Max = 0.71, Ave = 0.10, Meas = 0.47
NO: Max = 767, Ave = 237, Meas = 756

Results 25mph (2131 rpm):
HC: Max = 83, Ave = 20, Meas = 44
CO: Max = 0.58, Ave = 0.09, Meas = 0.10
NO: Max = 706, Ave = 199, Meas = 151

Work performed prior to test:
New universal cat installed on June 4, 2006
New 02 sensor
Fresh oil & filter
Swapped out JC chip for OEM chip
87 octane fuel in the tank
Pre-test drive for 20-25 minutes to heat up cat



Test date: 06/02/08

Odometer: 197,875
Vehicle condition/setup: only change from June 2006 test was install a 3.73 LSD

Results 15mph (1833 rpm):
HC: Max = 108, Ave = 31, Meas = 106
CO: Max = 0.71, Ave = 0.10, Meas = 0.11
NO: Max = 767, Ave = 237, Meas = 289

Results 25mph (2966rpm):
HC: Max = 83, Ave = 20, Meas = 33
CO: Max = 0.58, Ave = 0.09, Meas = 0.01
NO: Max = 706, Ave = 199, Meas = 0*
*no explanation why – the tech simply said, "you passed…..barely."

Work performed prior to test:
Reinstall cat (swapped in and ran my test pipe shortly after June ’06 test)
Replace 02 sensor w/ hardly used sensor
1 can of Seafoam in tank, 2 cans thru intake vacuum
Replace 2 cracked/worn vacuum lines on engine
Swapped out JC chip for OEM chip
Fresh oil & filter
87 octane fuel in tank
Pre-test drive for 20 minutes to heat up cat

For the record, I went to the same "Test Only" facility both times and the same technician ran both tests.

So what could be the reason for the borderline readings of the HCs on the 15mph runs? In the June '06 test, the cat was just a couple days old and then I removed it about a week afterwards (as noted above, I installed and ran my test pipe). The cat was reinstalled about a week prior to the June '08 test. Usually high HC numbers mean the cat is shot (or so I thought) which can't be the case here since its hardly been used. Your insight & wisdom is greatly appreciated.

Jon