Guys,

I just discovered that I'm missing some parts in my 81 vette

Can you help me out identify them ?


THANKS!!

 

The thing attached to the exhaust pipe looks like an oxygen sensor. I'm not sure they were on '81's. Has the engine been replaced?

 

From my limited experience ....plug on exhaust pipe is O2 sensor , next to oil filter is oil temp sensor and I believe the wire on distributor is a test wire ..not hooked up to anything normally .....
Good Luck ,Neal

 

The Distributor Radio Sheild is of coarse missing on top of the Dist unless You removed it for the Picture. All the Spark Plug Wire Sheilds are missing. Some sort of Sheet Metal thing behind the Oil Filter. The Engine Block should be Blue unless the Engine is Canadian built. The Sensor unpluged at the Oil Filter Boss is for a Oil Press Gauge and or Light but not in the stock location for a Vette. 81 was the first Year for a ECM so did they have an Oxegen Sensor? I'm going to Guess its got a Canadian Built Truck Block and or Motor in it and that probably means it has 4 bolt mains and is every bit as good as the stock 81 Motor.

 

Thanks for your help
I bought the car 2 weeks ago, don't know much about older corvettes,
Have no idea if car's engine was replaced.
Car is running, there are some small issues with it( headlights not going up, battery drain) and also there are some wires that are not connected, and i think emission system is partially missing.

my question is , how badly do I need O2 sensor ? oil gauge looks like it is working, needle goes up from 0 to 40 when car is running

Also Would you know where this green wire should be connected?

 

The distributor ignition lead on 81's was white. Seeing the wire tire holding things together and the loose white wire, I wonder if some non-stock "rewiring" has been done to your distributor.

The sensor in the block by the oil filter is for the oil temperature gauge. Your 81 would have been equipped with one of the optional ETR (digital) radios when new. The ETR radios had the clock incorporated into the digital radio face and had an oil temperature gauge in the center cluster, in place of the standard analog clock.

81 was the first year Federal emission Corvettes came with a computer (Calif Vettes had them starting in 80). 81 Catalytic converters had a fitting for the A.I.R. system, but I don't remember any sensors in the left exhaust pipe.

I'm not sure about the green wire. The plug on the end looks like one used at the heater blower motor, but I can't place the one in your picture.

I'll take a look at my 81, when I get to work tomorrow. I'm the original owner and nothing has been changed or removed from it. I'll let you know what the white wire and green wires go to on mine, and I'll look for the exhaust pipe sensor, too.

 

not sure if a 81 had 02 sensors but thats whats in the pipe. i believe they started that in 82 or 86. but by the looks of the pipe seems that might be a newer block and they just scabbed the the remains of the collector pipe that was already on the manifold to the exhaust that was already in the car. If you locate the numbers by the passangers head theres a lil flat spot with numbers and you can look up where, what, and when that block was in. the orange plug above the filter as everyone else has stated is the oil temp sending unit. the white and green wires not sure about.

 

The '81 C3 had the CCC ignition control system which used a computer, a special distributor, an electronically-adjusted carb, and the oxygen sensor in the exhaust to manage fuel mixture and timing on the car. It was the first such use on the Corvette. It was replaced in '82 [and '84] with a better system and fuel injection (CrossFire system using 2 throttle bodies). Then GM went to port injection systems in '85.

If all the stock equipment is there and functioning...including the sensors, too...the CCC system is pretty good for normal driving and more efficient on fuel use.

 

it looks like you have a pretty good 81 there peterec. sure some things arent working as you said but at least it doesnt seem to be messed with too much. my 81 had the sensor on the exhaust exactly like yours but that exhaust is long gone. the oil temp connection was there also just as your pic shows and you answered your own question, as that green wire you asked about is for your oil temp so normally it tucks into that black plastic tubing that runs down the back of the block .

 

Thanks Guys For you help,

I'm going crazy because of this car Felt in love with it but like it is with every woman, it gives me some hard time too...

Can you Guys recommend me a book that has all parts identified with names and diagrams what should go where?

One more question, I think my engine is leaking oil, as you can see from the picture there is oil all over engine, Recently I have changed the oil to Synthetic 10w30 ,
Does Old Cars require thicker oil? the engine has 54k miles,

 

Canadian built GM engines came in orange, blue and black just like any Flint or Tonawanda unit, were 2 bolt or 4 bolt and were fitted to many different cars and trucks built in either country.

The fact that the OP's engine is now black means that somebody has messed with it, but not much beyond that. Could be a new crate engine made in Mexico for all we know at this point.

 

How can I find out if that engine is original for my car?

Don't know the history of the car,

 

Look for the casting number, casting date and information on the engine stamp pad. This question gets asked several times a week so there's lots of details of where to find them if you search.

 

Look on the passenger side of the engine block, toward the front of the car. Just in front of the valve cover there is a pad with 2 sets of #'s on it. First one is the vin derivitive (last several numbers of the vin of the car for which engine was built.) The second # is the engine ID code. you can google small block chevy id codes and it will tell you what type of vehicle it came from. If you use the "search" function on this forum, you'll find plenty of threads w/ pics and descriptions of where to find these numbers as well as casting #'s for heads, intake, etc. Good Luck

-Nick

 

You have said the fuel efficiency thing before and I asked you where you get that info with no response? I am not trying to be a jerk, but mine without the CCC gets better than the original amount based on what I have researched. I will be glad to admit if I am wrong, but it seems to me that comment is misleading. The CCC will allow the car to run very well and be emissions compliant, but even running properly and optimally and brand new showed 15 and 21. I get about 17 and 21+ not a huge difference but it shows the CCC is not more efficient, and my motor is tired as well. Just askin....

 

My car is missing some Emission control pieces , my question is , can i completely remove all emission control parts? in IL cars older than 1994 doesn't have to go for emission test , Would that affect performance of the car?

 

The first thing I did was remove ALL of the emissions stuff, but do not confuse that with the stuff required to run the computer. I suggest you take a pic of your carb and distributor and post it, that will tell if the computer is still hooked up or not.

edit: it will not effect performance except make it better. Leave the PCV system in place, the rest can go in my opinion, but keep it in case the laws change...

 

Maybe you have already found out,but,the white wire was more than likely put in so you can hook up your hand held tach.