Hello, I have a 1992 Camaro rs 25th anniversary edition 305 T.B.I. v8. I have looked at the vacuum diagrams and I still have no idea. Could anyone tell ,me where the lines go? I will attach a photo, if you could be as specific as possible I would appreciate it. Thanks!

 

NVM I see you said you already looked at the diagrams.



Maybe this will help ?

 

Does anyone happen to know where the EGR solenoid is?

 

Mounted under the coil

 

Ok, thanks!

 

 

Also the throttle body does not have J that it shows in this diagram, any ideas?

 

The car drives really rough, I have found multiple vacuum leaks, and it has no o2 sensor, would that cause it? It bucks every now and then.

 

You're going to need to connect an O2 sensor, then connect a scan tool. Record any "codes", look at the data stream. Then clear the codes, and see what comes back. Again, the data stream will lead you toward any faults.

How you proceed from there will depend on what codes you get--if any--and what symptoms the car has.

Wouldn't hurt to check fuel pressure, cylinder cranking compression, and all the "usual" tune-up items--spark plugs, plug wires, cap, rotor, filters, check timing, test for powerful spark, etc.

 

Ok, thanks! I am not too mechanically inclined, so I really appreciate everyone's help. On that note I have another question. There is a line running off the EGR that connects to a T fitting. One side goes off and hooks to the engine and the other side is not connected. Any ideas where that missing line would go? I will attach photos.

 

Also, my throttle body only has three ports on the front, not four as shown in the diagram, ?

 

I have a TPI but that vacuum T leads to my cruise control vacuum reservoir. Its probably the same for TBI.

 

Would the port on the front left side connect to the EGR solenoid?

 

Thats what wildcard600 is showing. Cant help you myself on the EGR as on TPI (before I removed it) the vacuum port is on the front underside section of the tpi plenum.

 

That's hooked up wrong. The vacuum reference should go from the source, to the EGR solenoid, and from the solenoid to the valve. The three way check valve goes to the vacuum reservoir, the engine, and IIRC the HVAC controls thru the firewall.

The MAP sensor should be on it's own spur, and there shouldn't be a vacuum line to the AIR injection on an EFI thirdgen.

 

These diagrams, especially the EGR solenoid diagram are a bit generic, but you should get the idea. I'd ignore the tee off at #6 on the solenoid diagram, like I said, the diverter valve on EFI V8 thirdgens doesn't have a vacuum line.

 

Here's a better thirdgen specific vacuum diagram for TBI...



The five speed diagram is the same except it shows the vacuum line to the AIR diverter valve. Maybe that's correct, Idk, I don't spend much time around TBI cars. If you have a 5spd and still have the air injection hooked up, you're on your own.

Looking at your TBI, you have ports J, C, and A. Clean all the oil and poop off the casting and you'll probably find they're actually marked.




Hook your EGR solenoid up to J. Run a hose from the other side of the EGR solenoid to the EGR valve.

C goes to your PCV valve. The other valve cover needs a breather, or it goes to the tiny filter in the side of the stock air cleaner.

A goes to the charcoal can.

S you don't even really need unless you're running the stock aircleaner and actually using the Thermac for cold starts. Your car is EFI, you don't need Thermac. Even if you're using the stock air cleaner, the thermac doors default to open if you leave them disconnected from vacuum.

3-way check valve



The port on the back of your intake needs to go to the 3 way check valve, it needs to go on the side with a single hose barb. The barb coming straight out the other side of the 3 way valve goes to the vacuum ball under the driver's battery tray. The 90-degree barb goes to the vacuum line that goes thru the firewall to the A/C system.

I hope that's clear enough.