lou

I have just finished installing my air fuel gauge on my 80. I am using a universal heated sensor located aft of where the left and right exhaust pipe join. I wanted it to take readings on all engine exhaust. I have an Ideal ground between the sensor and gauge. When I first started the car, It took about a minute to get my first reading(lean). As the car warmed up, it gradually has gone to the full rich on the gauge and has stayed their ever since. I shut the car off for an hour and then turned the gauge system on without starting the car and it still is reading full rich. Is this normal, should this reading go back to lean when the engine is off? I want to make sure the system is reliable before making carb adjustments. Thanks lou :confused:

Budman68

How far back from the manifold is the O2 sensor? The gauge my start at rich and is not getting enough heat to work.

lou

I used a heated O2 sensor (three wire) because it is 24 inches back. The heated sensor seems to work for the situation since I got my first reading in under a minute. When I first started the car, there was no reading for about 50 seconds, then one LED lit starting at the lean end and slowly moved to the rich side, LED by LED. So I'm pretty sure it starts at the lean end. I would think when the engine is turned off it would eventually go blank(out of range) correct? :confused: lou

lou

Okay heres an update, after sitting for six hours, I turned the gauge on and it sitting at just below the ideal setting heading back towards the lean side. I know the feed back would not be real time but it is much slower than I thought. I'm going to head out on the road tommorrow and get everything up to running temp and see if this speeds up the feedback between the gauge and the sensor. Any one else got and air fuel gauge? If so, how fast do you get info on the gauge. lou

Matt Gruber

lou
mine reads max rich with the engine off.
There are plenty of carbs set too rich, so i would not be surprised if a carbed car was too rich all the time. The plugs would be grey/black too!
One guy put the sensor in the tailpipe; imagine the delay on that :lol:
i get feedback in real time. in case you missed my article http://community.webtv.net/MATTGRU/AFtesting


[Modified by drives61, 7:02 AM 12/31/2001]

lou

I know I'm running rich, I just wanted to get everything set up before I start adjusting the carb. We all know running to lean is a bad thing! :eek: heading out for a test drive right now. I let you know what happens. lou

rainman69

Mine is currently loacted 2" below the collector on the driver's side. It's stock exhaust, so I didn't want it in the manifold. I get realtime results...the A/F Gauge is constantly changing from one LED to another.

I'm using a non-heated Bosch O2 sensor from Advance Auto Parts that is the correct sensor for a mid-80's Corvette. It works great, starts at rich and backs its way down as the car warms up. Accurate within 1-2 minutes after starting. :smash:

lou

Good news! went for a drive and everything is working great. I am getting almost instant feed back from 02 sensor. I am running rich at idle. but thats why I got the gauge to do fine tuning. This is great. I will take some pics and post them tommorrow if anyone is intereseted in seeing the set up. Thanks guys!!! :D :cheers: Happy New Year!