I am in the process of replacing what I believe to be a failed air mass meter in my '92 non-turbo 240. Will know for certain after it arrives in the mail in the next day or two. While waiting for my purchase to show up in the mail box, I've been reading numerous posts and other info and have noticed that a failure of the hot/cold air delivery through the flapper valve in the air box is often cited as contributing to failure.

What condition contributes to the amm failure? An always hot air delivery or all cold air w/ no warm start up? The warm air hose and metal "deflector" that fits on the exhaust manifold are missing on my car. If a failed air valve which sends only hot air to the amm is the culprit, is it OK to run without the warm start-up air hardware? I understand that the absence of the warm air at start-up will affect emissions and driveability but I can live with those issues until such time I buy and refit the warm air "deflector" and pipe.

Thanks.