Heads up California

[markba633csi]

Just wanted to remind those in Cali don't ever buy a vehicle without a smog certificate- BMW or other.
I made that mistake with my '96 Z3 M44 and I'm paying dearly for it. Won't pass the dreaded low speed NoX test
and I've changed the cat and both sensors. Now it looks like there is too much carbon in the chambers and may
require pulling the head to clean. Chemical additives in the tank are proving to be ineffective. Beware.
I may end up donating the vehicle to charity at this point. The money I've lost? Just take a figure that would be painful to lose and double it.

The seller of a vehicle is responsible for providing a car that passes the test, even if it is sold "as is" or as a "parts car"
The only type of title that avoids that is a "junk" title which means the vehicle cannot be driven on the street
This is in the motor vehicle code. Whether the seller knew or didn't know if it would pass, doesn't matter.

 

[Duncodin]

I've heard the cat on m44 is a distance away from the engine so the cat takes a long time to reach working temperature. Giving it a quick test before fully warmed up will often fail - so I've heard.

 

[markba633csi]

Another thing I might add is that there is a fair amount of smog cheating going on- It would almost be a good idea on any car you buy
even if it supposedly passed the test is to do another off-line test just to be sure. Be prepared, be aware. Don't believe anything you hear,
and only half of what you see.
I hate the situation but it is what it is.

 

[t-tony]

Just wanted to remind those in Cali don't ever buy a vehicle without a smog certificate- BMW or other.
I made that mistake with my '96 Z3 M44 and I'm paying dearly for it. Won't pass the dreaded low speed NoX test
and I've changed the cat and both sensors. Now it looks like there is too much carbon in the chambers and may
require pulling the head to clean. Chemical additives in the tank are proving to be ineffective. Beware.
I may end up donating the vehicle to charity at this point. The money I've lost? Just take a figure that would be painful to lose and double it.

The seller of a vehicle is responsible for providing a car that passes the test, even if it is sold "as is" or as a "parts car"
The only type of title that avoids that is a "junk" title which means the vehicle cannot be driven on the street
This is in the motor vehicle code. Whether the seller knew or didn't know if it would pass, doesn't matter.

What are the exact emission limits vehicles have pass in Caifornia please?

Tony.

 

[markba633csi]

We have 3 tiers, and it apparently changes with vehicle type, engine size and year. I don't know if the entire set of data is printed anywhere
but for the '96 Z3 M44 engine the specs are as follows: (and measured for my first fail before converter change)

HC: ppm 15 mph rpm 1896 Max 60 Ave 9 Meas 19 ok
CO: % 15 mph ....................Max 0.53 Ave 0.03 Meas 0.00 ok
NO: ppm 15 mph ...................Max 459 Ave 67 Meas 709 ...... Fail

HC: ppm 25 mph rpm 2992 Max 43 Ave 6 Meas 15 ok
CO: % 25 mph.....................Max 0.51 Ave 0.03 Meas 0.00 ok
NO: ppm 25 mph.....................Max 746 Ave 62 Meas 394 .... Pass

Co2 and O2 are also measured but not graded as pass or fail
After the first fail I found cracks in all the rubber intake parts and replaced- no change
No codes are showing up, all monitors set, no check engine light
It almost seems like the max limits for NO are reversed between 15 and 25 mph- the more stringent test should give more leeway
One would think
I would sure appreciate if any members, especially California with a similar car could post their NO numbers please
-Mark

 

[IainP]

I post this all the time, to clean carbon off valves and chambers, spray water mist from a plant sprayer into the intake, whilst holding the revs 2.5-3K. The engine will stumble and you’ll need to keep the revs up. Massive amounts of grey ‘smoke’, really steam, out of the exhaust. Repeat at intervals until the ‘smoke’ is white.
Water is a fabulous scouring agent, the steam removes all the carbon from the chamber and exhaust valves/seats.

 

[markba633csi]

Thanks Iain I'll try that
I have done a similar trick in the past with my Datsun 510: route the windscreen washer pump hose to spray water directly into
the carburettor throat and activate the pump quickly a few times while driving at a spirited pace. Risky, but often works
A fine mist would be much safer- I'd be more careful this time and use a spray bottle

 

[markba633csi]

Oh by the way: Can anyone tell me what this item is behind the intake (between intake and firewall):