82 SC - No o2 sensor installed?
 

Is there a reason my car wouldn’t have an o2 sensor in it? Original CIS still installed.

I believe it was originally a California car, had the original thermal reactors installed which I swapped out to SSI.

[/HTML]http://forums.pelicanparts.com/uploa...1694366682.jpg

It depends on the engine. Please post the engine type code here you can find on top right side of the engine case close to the oil pressure sensor (not on the mounting bracket of the fan!)
Then we can figure out whether it used to have an O2 sensor or not. It's not that simple to modify a CIS engine from lambda control to non-lambda CIS system...

Thomas

http://forums.pelicanparts.com/uploa...1694373098.jpg


Probably deleted.

That's where the O2 sensor wire enters the engine compartment and connects to the harness "pin" under the fuel filter. Is the Lambda control unit still there under the passenger seat ?

http://forums.pelicanparts.com/uploa...1694389028.jpg

Yes it still is there.

Pictures of the Engine……..
 

Could you post a picture of the WUR by intake runner #2? Thanks

Tony

That's exactly not the type number, this is the serial number.

See this picture for more clarification on how to find the egine type number(yellow):

https://i.imgur.com/NKJ7OOf.png

Green is the location of the engine serial number.

Thomas

The Engine Number can be simply decoded:
https://www.stuttcars.com/porsche-911-engine-numbers-1965-1989/

So 64c0361 results in a 1982 SC for the US market coming with a 930/16 engine.


Yes a Californian car but in 1982 no thermal reactors we used, just a very efficient 3 way catalyst system.

So, check if all other lambda control based components are still existing and if yes, then simply buy a new sensor and re connect it.

i`d say do not worry too much about the o2 sensor..you do not need it at all.Back in the 1980-90 in california we did disconnect all that stuff on 911 Sc cars....the engine will run without it much better...


Ivan

930/16 ! Thank you.

http://forums.pelicanparts.com/uploa...1694483468.jpg
http://forums.pelicanparts.com/uploa...1694483648.jpg

If "all" of the lambda components are working properly and the ECU is in perfect condition it has a lot of advantages, beside no performance loss, a better mileage and all benefits regarding proper fueling.

Ok ,if you say so Andrew;-)..without O2 sensor the engine will run very good and the difference on fuel consumption is very very little...that goes for 911SC and Carrera too....
Ivan

Don't want to blame you - you may be right. my personal experience is complete another story...

When I bought my SC, lambda control and the whole CIS was out of order: Wrong WUR, dead O2 sensor, worn injectors, misajusted injection begin, misaligned fuel distributor, way too rich mixture, dead TTS, massive vacuum leaks, crushed airbox etc. But the car started and ran somehow. But overall the mileage was poor and the performance wasn't what to be expected with the camshafts and Dansk exhaust. All in all, the entire CIS including the lambda control did not worked properly.
After a long examination and get myself introduced to CIS, I can say that the CIS is a very good injection system for that time and is still today with very good performance and mileage. The car starts quicker than any other of my cars - at any temperature.

If you change some of the components or "tune" the CIS because some things do not work any more - which is quite possible (and this is of course the main problem) - you can tune such an engine to run somehow: Either for top end performance or for a good start, but this is always a bad compromise.
It depends on you what you expect from the car: On racetrack you drive the car “digitally”: WOT or idle... starting difficulties and mileage are not in focus... the other way around - rolling around on Sundays with your partner on the passenger seat, the WOT power doesn't matter...

Thomas

Yes ;-)

Very well.some peeps like to have it ..but most of the 911 owners around the world do not.It is just an emission crap;-)..totally unnecessary stuff on the 911 engines....

Ivan

81 sc /16,
Stock, -cat, o2 connected, primary pressure 4.8 bar, control 3.4 bar, wur within spec and set to slightly richer end of cold warmup spec, original fuel accumulator (tried a new one as preventative maintenance with same part number and it was a struggle to start right with wur in spec, so changed back)

Starts beautifully, no stink at all, all conditions, terrific power, smooth, I can't see a car running any better. But it takes some time to get it just so and any shop would go bankrupt.

With O2 connected:
FV idle set to 45% duty cycle or below, car pulses at 2500-3000 rpm in 2nd/3rd gear cruising. (less torque I thought below 6200 rpm but able to pull to 6400 rpm)
FV idle set to 50-55% duty cycle, car is smooth all rpm, all the time, seems like more power below 6200rpm and less above that.

I think porsche has the max enrichment setup perfectly for this car at the specifications they've provided. That being said, I think that over 6200 rpm is when full enrichment above 65% FV duty cycle might help and I'll mod the ecu circuit with input from rpm for that specific condition one day.


John W, gave a co level that works for him, I'd like to compare for myself, you know it's going to work well, between him and proporsche they have hundreds of these under their belt.

For those with properly tuned O2 connected cars (cis), have you tried pulling the o2 sensor to backup your opinions using the CO levels set as John recommends?

Phil

Hmmm, Crap, I see.
I never knew that lambda control comes only with benefits for emissions. Honestly and with no offence but you should get a bit more into the combustion subject.

ok i do that ;-))))my 40 years on these beast ..and .i know nothing....enjoy your expertise Andrew...

Ivan

don’t make it dramatic, I never claimed that you know nothing.
Just have a beer, as you brew, one of the bests, and that makes you less thinking of things that could be just crap.