Re: Causes for an AMM failure code?
I didn't remember exactly what the code said. Come to
think of it I think it did state" signal from AMM missing" for that
code. So it looks like I need an AMM.
The part number I gave in previous post is correct, that
is what this car has installed! It's Bosch # 281101A
It's not xx012 or xx016, it is exactly as above.
On Sat, 22 Oct 2005 11:14:14 -0700, "Randy G."
>Geronimo <firstname.lastname@example.org> wrote:
>>Re: my 89 740 B230 non-turbo Gl sedan that is down: Very hard to
>>start, you have to give it LOTS of gas, it won't idle at all. It dies
>>when you put it in gear:
>> It has a code set for "air mass meter failed". But I have a bad
>>air duct that really needs replacement.
>Is it the one before or after the AMM? If after, repair it with epoxy
>for plastic or RTV to see if that is it. If before, it will have
>virtually no effect on the AMM.
>>It doesn't have a rigid
>>plastic duct like the turbo has, it is flexible/corrugated. it has
>>gotten soft and was collapsing, and because of the rediculously high
>>price of a new air duct, I wrapped it up with metal tape.
>Ya- that will work temporarily. Go to a wrecking yard and get a
>>The ends of
>>this duct are different sizes...so I couldn't just buy a generic flex
>>*metal* one off-the-shelf from a local parts dealer. I need to go back
>>out to the car and unwrap the duct and see if maybe it has split or
>>something, which would let unmetered air into the intake. If this was
>>happening, could this trick the computer into thinking that the air
>>mass meter is bad?
>No, I don't think so.
>>Seems like this would cause it to set the mixture
>>completely wrong, at the least, right?
>Yes, but wouldn't cause the code. The code states, "Bad or missing
>signal to or from the AMM."
>> Yea, this engine doesn't have a "limp-home" mode in reality,
>>because when the car was working OK, I once pulled the conn. off the
>>AMM, and the engine didn't just run badly--- it wouldn't idle at all,
>>and was undrivable!
>You might have other problems as well. With the AMM disconnected it
>sould run- very rish and not over about 3500 RPM.
>> Does anyone have a spare used AMM, P/N 281101A? Even if it proves to
>>be just a matter of fixing the duct, I still need to get one to have
>>around for when the AMM really does fail, if it turns out to be in
>>fact good now. The local junkyard doesn't have any89-92 740's.
>I think the number you need is the Bosckjh number, like xxx xxx xx 012
>or such. Post the number here- maybe someone can find one at a yard
>BE SURE to check the air box heat riser control thermostat for proper
>opreration. IT MUST NOT allow hot air in once the car is warmed up or
>in a temperate climate. If in doubt- replace it! The hot air will kill
>a good AMM.
> __ __
> Randy & \ \/ /alerie's
>'90 245 Estate - '93 965 Estate
> "Shelby" & "Kate"