Subaru Legacy 1992 wagon
I got a salvage air cleaner box. The car shop jockies have, over the years, cranked the bolts too tight which resulted in the plastic box breaking where are the nuts inside recessed holes that hold them in place. I'm on the last good screw and the one diagonal from it holds just enough to keep the top onto the bottom half of the box. I got a box from the salvage yard and it looks okay so I figure on popping out the old one and use the salvaged one.
On the box or attached to it is the MAF (mass air flow) sensor. I also got that with the salvaged air cleaner box but obviously I don't know its condition. I've always had a cool+wet weather running problem where sometimes the engine just gets way too much fuel so it is running rich. Not only does the engine have to get up to temperature but it has to be at running temperature for quite awhile. I'll get to work and it's still running rough. Then it sits for a couple hours, I go use it again, and it's running fine again. It will stall at lights because it chokes on seem to be getting too much fuel (I can smell the fuel stink even after driving 10 miles, or maybe it isn't firing because it's too lean and the unburnt gas is getting pumped out the tail pipe). Had lots of stuff looked and replaced over the years but no one came up with a solution, plus everytime I left it at the shop so they could start it cold then problem didn't show up. It is highly erratic when this happens. I'll go out to start the car, it's heaving trying to stay running, I put in neutral and rev the engine to 2800 RPM and leave it there for 10-15 minutes (so it gets up to running temperature and been there for 5 minutes), turn it off, go back inside for an hour, come out and it's running okay again. Very frustrating. I suppose it could be the computer but I'd rather try something cheaper (and easier). Maybe the MAF sensor is malfunctioning or dirty so the computer sees the wrong amount of air getting delivered.
Usually the answer (by the dealers) to replace the MAF sensor. Yeah, but expensive. And I'll have 2 of them: my original and the salvaged one. So I'm thinking of using CRC MAF cleaner spray on the salvaged one and see if cleaning it helps. If not or it gets worse, I'll just put my old one back (and uncleaned so it's in the same state as when removed). Apparently when you turn the engine off, the wire inside is heated to burn off any contaminants but it doesn't always work so a film accrues on it. I figure I don't have much to lose on cleaning the salvaged one other than the cost of this special cleaner spray. However, I'm wondering if there is any calibration to the MAF sensor or if it is just swap and use (when, for example, you install a new one at full cost).
Is this CRC MAF cleaner any good? (Found an example listing at