I recently picked up a 94 3.4 automatic with 27k miles. It's been sitting for a long, long time and I've got a list of issues to sort. I'm taking a trip down memory lane as my first Camaro at 17 years old was a '94 V6, back in the late 90's...

One thing that's confused me is when I have it hooked up to my Actron OBD-I scanner, the data stream says AIR pump is ON. I believe these turn off shortly after cold start. Scanner says it's still ON even though engine is at full operating temp, 195, so I went looking for the pump. The car has a fuse for it... but I don't think there is one, or that it ever had one. I don't remember my old '94 having one, but that was a long time ago.

Did '94's have an AIR pump? And if not, any guesses as to why the scanner thinks it's on?

 

Factory service manual shows a secondary air pump. Appears to be located on the driver side subframe near the front of the engine. Look at factory service manual page 6E3-C6-7, and there is a diagnosict logic chart that covers “Engine in open loop, run engine to 3,300 RPM, air pump should turn off after approx 5 seconds”.

If the air pump runs in closed loop it’s really going to mess up the A/F ratio and run extremely rich.

 

Uhhhh...Why guess? Listen for the air pump running. It's not that quiet. Put your ear close to the ground on the front driver side.

 

That's why I'm confused. I don't hear or see one--or the necessary plumbing for it. But the car has a fuse for it, and my basic little OBD scanner says it's "on".

I found a single post from over 20 years ago on a V6 message board stating that the A4 cars didn't receive one in 1994, only the M5's with the V6, and the LT1 cars:
https://www.camarov6.com/forum/techn...-air-pump-3-4l

That makes no sense to me. The Factory Service Manual doesn't make any reference to differences between configurations.

 

Does it have a dedicated breaker in the under hood box? Factory service manual shows it. I have to look closer to see if there is in asterisk or a note indicating not all models.

I did notice there are no DTC codes for the air pump. Again it doesn’t differentiate between transmission types.

 

Mine has a relay and fuse for it, yes.

There is a '94 3.4 5-speed that newly arrived at one of the parts yards so I went to take a look at it today to kill time and maybe score some parts. Sadly, the car was already picked over pretty well and what was left was heavily worn (215k miles). Surprisingly the T5 transmission was still there, but who knows if it was any good. Anyway, it still had an air pump with plumbing right below the ABS block, and the under-hood fuse box was still there, same fuses/relays as mine. So, I've confirmed I definitely don't have one, but the question still remains: Did A4's of that year actually come with them?