A/F meter reading lean

[fisch]

I have never used an A/F mete before and am not sure if it is working. My dime came with a narrow band Halmeter AF10. It is a LZ22 with Z Therapy 46 SU's. Car has sat for 2 years, but the Halmeter was working before it sat and would read.

I did nothing to the car, adjusted nothing, but two years later the meter is pegging the lean side of the meter. It doesn't fluxuate at all no matter what I do, no matter how much gas I give it.

As a quick test it was suggested I warm up the car, then pull the choke while running and see if it goes 'rich'. Pulled it, the car sputtered and stalled out, but the meter did not move.

If it is really that lean, I don't want to blow anything up, but again I know little of these things.

What do y'all think? I will pull the spark plugs and see if they can tell me anything. I can find no info on how to test this Halmeter AF10. Thinking it was a clogged fuel filter, I replaced it. Same. The headers feel brand new and I see no exhaust leaks that are visible prior to the meter. I went through and cleaned all the fuses too.

[DISLEXICDIME]

sounds like the 02 sensor is toast

[Sealik]

Pull sensor and power it up/turn it off...then re-install it

If it still doesn't work.... toss it in the garbage... :D

[metalmonkey47]

I wonder if the sens-wire is shorted to ground. 

[fisch]

Thanks guys. I wondered that too MM. Trouble is, of course, this thing is installed where I can't even get a hand on it. So I have to figure out how to get to it and the wires. It is on a short piece of pipe just after the header ends, so worse case I can remove that piece of pipe to get to it.

 

OK so that is next, pull the 02 run it, Shut it off, put it back, start it up.

 

So am I right that pulling the choke enough to kill it should have made it read rich? It can't be choked enough to kill it and still be lean, right?

[metalmonkey47]

Thanks guys. I wondered that too MM. Trouble is, of course, this thing is installed where I can't even get a hand on it. So I have to figure out how to get to it and the wires. It is on a short piece of pipe just after the header ends, so worse case I can remove that piece of pipe to get to it.

 

You can alsways finds sense-wire and check with a ohm-meter to see if you have continuity w/ ground. If so, short to ground. If not, replace the POS :P 

[Sealik]

You can alsways finds sense-wire and check with a ohm-meter to see if you have continuity w/ ground. If so, short to ground. If not, replace the POS :P

 

Even if there is continuity....the sensor still might need to be re-calibrated in fresh air

That said...I would toss that narrow band POS...lol

 

Not sure what needles you are running in those 46s...but you could be running really rich at WOT etc

[fisch]

Thanks Selik! I hear you about the narrow band, it just came with the car! According to the PO the needles were a custom profile. But he says "I had it set up to run pretty lean at steady state cruise and to swing rich at wide open throttle." Chris (PO) has been super helpful with what he can remember about the build. It was a reliable machine for him, taking him all over the country. Heh he drove it to my house from Maine to deliver it!

 

As long as I know pulling the choke enough to stall it while warm 'should' have made it read rich- thus faulty meter, I am ok testing this further without blowing it up.

 

OK so pulling the o2 and running it, then reinstalling it is how you recalibrate these things? Will do. Wish I had Cee Lo Green's baby sized hands for the job.

 

[Sealik]

Yes..the 'choke' drops the seat away from the needle....thus producing a rich mixture

Those fancy disco lights should of flashed a different color....lol

That said...narrow bands are a lot slower in displaying info.... then widebands.

Also...if you're already running rich at idle, I doubt the narrow band will pick up 'anomolies' if the SUs are fully choked?

 

I believe all WBs need to be calibrated in fresh air.....and at certain intervals 'down the road'.

Can't remember if I had to calibrate my narrow band or not.......I assume I did.

 

I had to make custom needles for my LZ23

 

I doubt I would of attempted this without a WB