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BMW E36 M3

The BMW E36 M3 is the first target of my alternative affections, it's quite

the opposite to a Lancia Delta, but offers a few positives in California

that a Delta can't. First being, you can get them here!

In the USA!

The US version of the E36 M3 has 80bhp less than the last of the European E36 M3 models, it also has a few things missing, but what's left is a cracking little car.

The story goes that BMW was not eager to loose huge swathes of cash again, trying to sell M3s to the US.

The previous model E30 M3 was so expensive, and even at the time its performance was a little lethargic. So when BMW decided to replace the E30 M3, they simply left the USA out, US customers didn't want the E30 car, the new one would be even more expensive, so sod that!

That's when the BMW Car Club of America started to bombard Munich with letters requesting the new M3. BMW had done a little switcheroo on the E36 M3, and given it a metric tonne of power from a 3ltr 6 pot, and it went like mad!

So eventually the USA got their own M3, but with a caveat. The US model was getting only 240bhp, rather than the 285bhp in Europe, and things got worse. A single throttle body, 328 derived block and head, no floating discs and weaker calipers, plus a light weight diff. Who on earth would want this thing?

Well, lots of people wanted it, the car was a huge success compared to the E30, and because lots were sold, there are lots to choose from down here. This M3 is in fact a great car, which is light and nimble, and really rather fast. It sounds good, and doesn't have exotic parts like individual throttle bodies to complicate the maintenance process.

This is the recently purchased M3 in my garage. It's a 1998 car, whose directly comparable European M3 now had 320bhp from a 3.2 ltr engine and a 6 speed box.

My car runs well, and looks good as only a So Cal car can, the body is as new, and the interior has stood up well.

The interior vinyl and plastic parts can be badly affected by the intense sun here, but this car must have been garaged.

I bought the car, but the owner forgot to tell me it hadn't lately been smog tested, so the first job was to get that done.

CARB stands for California Air Research Board. Due to huge levels of smog in the 1970s to 90s, CARB introduced tough limits on tailpipe emissions, mainly Nitrous Oxide and  Carbon Dioxide. To get a smog test in California you need the car to be bone stock,

and to pass ever more restrictive tailpipe emission targets.

This is why a Lancia Delta can't be legally registered and used in California. Other states in the US have lower standards, so a Delta could be registered in another state and visit California, but it couldn't live there.

So I took the M3 for a smog test, and although the testing sites can look a bit casual, the strict standards set are enforced.

The BM failed.

Now a search on BMW chat rooms shows that M3s failing smog tests is a common problem, the car is fighting a loosing battle as the limits come down every couple of years. The advice centered around the O2 sensors which are responsible for sniffing out the amount of oxygen in the exhaust gasses. Even though there was no warning light or code these sensors do slowly fail, and when they do the ECU gets tricked into over feeling, and this is what creates elevated hydrocarbons and N0X which means fail.

Cheap as chips O2 sensors were snapped up off amazon

for 60 bucks a pop and thrown on the car before the cats.

This made a big difference to the rich black puff you’d get

with your foot flat, but wasn’t enough to get through a

second smog check.

The numbers were much better though, and the O2 sensors

had cleaned all the N0X up, but had failed to clean the

low speed HC. This seemed to match every other forum E36 owner at about 20 parts per million above the limit.

With Fail number 2 under my belt I went out and bought

another bargain Celica Supra to soften the blow.

Once that was put away, I went back to the BMW and had another go at it. 


Even a loose oil cap can effect emissions


The entire emissions system is made up of lots of interlinking systems, and if just one is out of balance the car runs rich, so all the other possible trouble makers had to be done too. The first fix is nice new oil, and thicker is best on high mileage engines - burning oil produces hydrocarbons. Then a panel air filter to increase air flow and clean the MAF with a little rubbing alcohol and a q-tip.


A very kind fella at the bummer dealership gave me some Tecron injector cleaner which went in with a full tank of high octane Shell juice. I ran the fuel through which allowed the O2 sensors to bed in with the ECU, and it cleared out all the old carbon deposits that were left from the car running rich. The last advice I saw on the BMW forum, and the most appealing, was drive the snot out of the M3, then take it straight to the Smog station, burning hot cars run leaner. So after a monumental Mullholand thrape I stopped at a petrol station for a final fill up, before going for a retest, but noticed the station had a smog bay and a lonely chap waiting to smog. I rolled the dice that Friday afternoon and came up deuces! The M3 got a pass, and it was but the tiniest of margins, i think the difference was that Jose was actually trying to pass the car.

The smog tester actually wanting the car to pass makes a big difference. Some cars, like my M3, are so marginal that an unsympathetic tester can easily take the car over the emission limits. However, luck was with me this day, and we live to motor for another year.

A real big help

The beemer finally passed the smog here, this mechanic was very helpful. He knew that with care our M3 would pass the test, and it did, just!

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