I just made the AMM tester that is shown in the FAQ's.I put the the tester in the blue connector that has the pink wire.I hooked everything right as I thought.The O2 is switching back and forward as it is suppose to.I checked the OHM reading on the AMM pins 2&6 this checked out at 300 OHM's.The led light doesn't switch off and on as I thought it would.I switched out 3 AMM still no luck.When the engine is reved the led does go off.Am I doing something wrong.
Rodney

You must turn the screw on the AMM back and forth until the lights starts to flash. Then tweak it some more for equal time off and on, this fine tunes the mixture. It is normal to see the voltage swings on the O2 sensor output even though the test point light is not flahing. If the amm is so far out you will not even see the O2 voltage swings. If the light goes off when you rev it it sounds as if you are close. Keep track of your turns as you turn the screw.
BTW a normal analog meter will do the same as the light.
--
David Hunter

Could someone tell me were to find the DIY AMM tester in FAQ. I looked but couldn't find the site ? Thanks.

I stayed with the car and got the AMM adjusted.
I just hadn't made enough turns to the left are to the lean side.
I wasn't able to get a 50% duty cycle but it's close.
Thanks to those for your help. If you have a LH2.2 and don't have one of these in your tool box you are losing money in the new liquid gold (GAS).
Rodney

here it is:
http://www.brickboard.com/FAQ/700-900/EngineFuelinjection.htm#SettingBaseIdle

Tom

The LED should be blinking at an approx. 50/50 on/off frequency. The LH2.2 AMM allows you to tweak some internal voltage by turning the screw that sits (I think) to the right of the large connector on the wiring harness. The manuals I have all say that there is a plug that should cover the screw which may be the case for you. On two cars of mine that had LH2.2 the plug was missing which probably means they were tweaked prior to my ownership. If the plug is still on the AMM, drill two holes side by side into it and take a pair of needle nose pliers to pry/pop it out therefore exposing the screw...

When I set up my car after installing a new engine it took ~5 full turns to the left to get the LED to blink.

The signal that feeds the LED is the voltage swing of your O2 sensor. When was the last time it was replaced? If it's rather old, a new one will likely improve your gas mileage. Do a search on the BB for "Ford Mustang oxygen sensor", the O2 sensor that the Ford 5.0 liter engines use is the same as for your car. The only difference is the connector...which can be cut off the old one and crimped onto the new sensor. The Ford sensor costs ~$40 at your local auto chain vs. $120 for one that is made to fit your Volvo.

Good luck,
Bean
--
'80 242GT 93k, '94 945T 149k, '89 765T 71k (new '94 B230FT)

The plugs are out of all of my AMM I want to know why the LED is not blinking.
The O2 is switching as it should.
Rodney

You have to adjust the potentiometer with a slotted screwdriver. While measuring the resistance between pins 2 and 6, turn the pot and you'll see the resistance changes. It's a good idea to count turns; when you get to either end, the pot keeps turning but the resistance won't change (I believe it's 20 turns, end to end).
--
David Armstrong - '86 240(350k km?), '93 940T(270k km), '89 240(parts source for others) near Toronto

What is the base setting for the AMM when measure for OHM's mine is at 300 OHM's. I know how to turn the screw. I want to know why the LED doesn't blink.
Is it turn to the left for lean and right for rich are what.
Rodney

I rechecked my notes. The pot has 15 turns to it.

If the test point voltage constantly reads high (no LED), the mixture is lean; constantly low (LED on constantly) is rich.

Turning the pot clockwise makes the mixture richer; counter-clockwise is leaner.

If you hook up the AMM tester between the test point and 12 volts, there is still 2 ways to connect it; try swapping the test point wires between test point and the 12 volt connection. If the LED is connected the wrong way, you will never get it to flash.

--
David Armstrong - '86 240(350k km?), '93 940T(270k km), '89 240(parts source for others) near Toronto

The adjustment range is 0 - 1000 ohms. With the engine warmed up you adjust the screw so that your led blinks at ~ 50% duty cycle. Basically you are tuning the the amm to agree with the O2 sensor. The O2 sensor controls the mix after it's warm, but until then the amm is in charge and you want it to give a mix that is the same as what the O2 sensor would. I don't remember which way you'll have to turn the screw but if you count turns you can try each direction and always get back to where you started.
Good luck,
Tom