o2 sensor etc.

911Jarle · 12-29-2010, 03:14 PM

Hello guys!

I have a couple questions about o2 sensor, and removal of it.
My car is a 1978 SC with a 3.0 SC engine, not sure of the year of the engine, it has been swapped.

This year, I removed the CAT, and later on I swapped the exhaust.
I could not see an o2 sensor in the cat, but there was a small pipe exiting the muffler itself.

Just out of curiorsity, where is the o2 sensor located, and what was the pipe exiting the muffler, at this stage it is temporarily bent to the side..

I would expect the o2 sensor to be in the cat, at the time of the cat removal I gathered earlier owners had gone to the trouble, removing the sensor and adjusting the motor to that.

Thanks!

Cheers, Jarle

Roby466 · Roby466's Garage

I don't think that your 78 sc has the ox sensor... didn't only start in 81?

911Jarle · 12-29-2010, 03:44 PM

Quote:

Originally Posted by Roby466

I don't think that your 78 sc has the ox sensor... didn't only start in 81?

It has a replacement engine, that I do know.
It also definately had a cat, that's for sure.
But there was no sensor in the cat, and neither in the ex manifold.

Anyone know the different locations here on different models?

Thanks!

Cheers, Jarle

steely · 12-29-2010, 04:08 PM

My understanding was that the O2 sensor should be as close to the exhaust manifold (but in the cat) as possible to help it heat up. I really don't know if it's been done differently.
There should be a 30-40cm cylindrical connector for it on the left rear fender near the coil or fuel filter. Is yours attached to anything?

911Jarle · 12-29-2010, 10:48 PM

Quote:

Originally Posted by steely

My understanding was that the O2 sensor should be as close to the exhaust manifold (but in the cat) as possible to help it heat up. I really don't know if it's been done differently.
There should be a 30-40cm cylindrical connector for it on the left rear fender near the coil or fuel filter. Is yours attached to anything?

When I removed the cat, there was no sensor in it. So, if that's the location, it was definately removed.

Hmm.. That small diameter pipe exiting from the exhaust\muffler did that have something to do with the airpump perhaps?

Thanks!

Cheers, Jarle

javadog · 12-30-2010, 05:58 AM

Jarle,

Look at your engine and find the type number and serial number. Then, we'll know what you have in there. The '78 and '79 SC in some markets had a cat but it was different than the ones used in 1980 and later, when the O2 sensor was used. Shoot a picture of the muffler also, there were a couple different ones that had a small pipe going in to them.

JR

911Jarle · 12-30-2010, 02:45 PM

Quote:

Originally Posted by javadog

Jarle,

Look at your engine and find the type number and serial number. Then, we'll know what you have in there. The '78 and '79 SC in some markets had a cat but it was different than the ones used in 1980 and later, when the O2 sensor was used. Shoot a picture of the muffler also, there were a couple different ones that had a small pipe going in to them.

JR

Hey!

Will shoot a photo of the enginenumber tomorrow.
Hopefully that should shed some light on the matter.

Regarding the small pipe to the muffler, anyone know what it's for?

Thanks!

Cheers, Jarle

javadog · 12-30-2010, 03:18 PM

Quote:

Originally Posted by 911Jarle

Regarding the small pipe to the muffler, anyone know what it's for?

It depends on what muffler you have, which is why I asked for a picture of it. Some of the mid 70's US 911s had a small line going to the muffler as part of the emissions control system. Early turbos had a pipe going from the wastegate to the muffler.

JR

911Jarle · 12-31-2010, 02:10 AM

Quote:

Originally Posted by javadog

It depends on what muffler you have, which is why I asked for a picture of it. Some of the mid 70's US 911s had a small line going to the muffler as part of the emissions control system. Early turbos had a pipe going from the wastegate to the muffler.

JR

Hey guys!

Found this number on the engine:
930 105 111 0R
What does that tell us?

The muffler is a turbo muffler I think..
Including a picture of the end piece here.. Do not have it available you see.

Thanks for the info guys!

Cheers, Jarle

javadog · 12-31-2010, 04:59 AM

Jarle,

That's not the engine number, it's a number cast into one of the engine case castings. The engine number should be something like 930.XX and you should find it stamped on the engine case, to the right of the cooling fan. The engine serial number will be nearby and will probably be 7 digits. That does look like a turbo muffler, in which case the extra pipe was for the output of the wastegate. It would need to be capped on a normally aspirated car.

Thanks,
Jeff

911Jarle · 01-01-2011, 05:53 AM

Quote:

Originally Posted by javadog

Jarle,

That's not the engine number, it's a number cast into one of the engine case castings. The engine number should be something like 930.XX and you should find it stamped on the engine case, to the right of the cooling fan. The engine serial number will be nearby and will probably be 7 digits. That does look like a turbo muffler, in which case the extra pipe was for the output of the wastegate. It would need to be capped on a normally aspirated car.

Thanks,
Jeff

Hey found two numbers

63D 4945

930\10 Did not see anymore numbers close to this location.
Both numbers where close to the fan, on the right..

Are these the numbers I'm looking for?

Happy newyear everybody

Cheers, Jarle

911Jarle · 01-01-2011, 05:59 AM

Quote:

Originally Posted by 911Jarle

Hey found two numbers

63D 4945

930\10 Did not see anymore numbers close to this location.
Both numbers where close to the fan, on the right..

Are these the numbers I'm looking for?

Happy newyear everybody

Cheers, Jarle

From what I can understand, this means it's an SC engine, 1983.
Not US from what I can understand? Not even cat's?

Apparantly when they swapped in the donor engine, they didn't connect the o2 sensor simply because there is none? But the cat was just left there.

Are my assumptions right here?

Thanks guys!

Cheers, Jarle

javadog · 06:21 AM

Quote:

Originally Posted by 911Jarle

From what I can understand, this means it's an SC engine, 1983.
Not US from what I can understand? Not even cat's?

That's what it looks like. 1983 Rest of World (European) SC. No cat, just a pre-muffler in it's place. No O2 sensor; it will have the non-frequency valve version of the CIS system, and no wiring and control unit needed to run an O2 sensor, either in the car or on the motor.

It would be interesting to see some pictures of the exhaust system. A turbo muffler won't bolt up to a stock SC exhaust.

Cheers,
Jeff

911Jarle · 01-01-2011, 06:30 AM

Quote:

Originally Posted by javadog

That's what it looks like. 1983 Rest of World (European) SC. No cat, just a pre-muffler in it's place. No O2 sensor; it will have the non-frequency valve version of the CIS system, and no wiring and control unit needed to run an O2 sensor, either in the car or on the motor.

It would be interesting to see some pictures of the exhaust system. A turbo muffler won't bolt up to a stock SC exhaust.

Cheers,
Jeff

Next time I have my car on my lift, I'll shoot some pictures of it.
Earlier there was an insane turbo engine in the car. They didn't want to sell it with that engine because it was more than a handfull to drive.

My guess is that they kept everything they could, so probably fitted the muffler somehow instead of buying a new exhaust. I have since then fitted a Dansk sportmuffler with the 84mm pipe.

Actually I'm sort of relived the engine is a non o2 sensor type. Less things to worry about

Thanks Java for your help.

Cheers, Jarle