Engine emissions parts
 

I'm looking for some information on the emissions on our cars. I'm doing a restoration and everything will be original, but most of the emissions on my car had been disconnected.

There is a thermostatic switch in the intake manifold next to the water neck. Does anyone happen to know what this part is for and what it's part number is for a carb 86 305?

We haven't been able to find it at the local parts store and I haven't been able to find in my service manual or online.

Thanks.

Re: Engine emissions parts
 

That should be your temp switch that tells the computer the temp so it will turn on the fans if I am not mistaken. The p/n at Autozone is SU109.

Re: Engine emissions parts
 

That switch I have, the one for the water temp that turns on the fan.

I believe I may have figured this one out. It seems there are 2 systems with thermostatic valves (not switch, my mistake) on the front of the intake, one in the water outlet neck, and on directly in the intake.

If someone could correct me if I'm wrong, according to my service manual for the 86 TA, the valve in the water neck is part of the EFE system. The valve directly in the intake is for the EECS, which according to the service manual is a normally closed valve that opens at 170 degrees to assist in the purging of the charcoal canister.

Of course my service manual doesn't give me a part number for this, only its purpose and the temp at which it opens.

If anyone has any more information, or even pictures of a functional emissions system, that may help me, and hopefully others who may be doing a restoration who found a car with the emissions disabled.

Thanks.

Re: Engine emissions parts
 

I do have those numbers as I replaced both "switches" on my 86 305 carb Firebird awhile back. I'll have to dig them up. Seems like I posted some info on this on this forum, did you do a search?

Joel

Re: Engine emissions parts
 

Got lucky, found them.
I refer to them as a ported vacuum switch: the one on the thermostat housing I found new at GM #14007803.
The one in the intake manifold was a lot harder. Every one I ordered from GM had wrong threads. So, I used a BWD #EC920 for that one. My OEM number for the intake was 3031385 if that helps.

Joel

Re: Engine emissions parts
 

Thanks for the info.

I did a bunch of searches over the past year or so that I've been a member of thirdgen for emissions info. It seems most people are more interested in how to remove the emissions than to make it work.

Unfortunately, where I live, all emissions components must be in place to pass inspection (they don't need to work, they just have to pass the visual inspection).

But since I'm doing a restoration as close as I can get back to factory as I can, I'd like all this stuff to be accurate.

Anyway, thanks again for those numbers. I will pass them along to the parts store to see if they can get them, or at least cross over the numbers for parts that will work.


*** EDIT ***

I did a check on that vacuum switch, and it lead me to Advance website which says it does not fit an 86 TA. I'll have to check my intake to see what it's number is. I can't see why they would have a different intake on a TA vs. a Firebird with the same engine in it, but I guess you never know.

If it's the same intake, I'll get that switch since you said it works in your car joeld.

Re: Engine emissions parts
 

Yea, that is the switch I had problems finding. And it is possible that your engine code is different. Is yours code H or G?
It took me about 3 weeks of ordering parts from GM dealer and parts stores to get the correct thread and port size.
This actually looks to me like this switch might have been a "rolling" engineering change during the build year/years. It is quite common for this to happen.

I finally found mine(BWD EC920) at Advance. They ordered 3 different numbers, and this one fit and funtioned properly. I use the Well's site a lot to cross check and find parts.

http://www.wellsve.com/ecatalog.html


Joel