just got this 95 b150 for 500 bucks, runs ok just a little rough and makes this upper engine noise? is this typical to these? just wondering if there is a common part failure, its got 205k miles, compression is 130 all around, and vacuum indicated no valves sticking open, spark plugs indicate very lean running condition(white tips), i notice my map sensor reads 11 inhg and the vacuum gauge is reading about 19 or 20 at idle, maybe the map sensor is causing my lean condition and the noise is spark knock? any insite or info would be great, i have a scan tool and can read live data so if someone could use more info i can get it, thanks... david

 

well map sensor is all good, mistake on my part thats what it should read.

basically anyone else have a problem like that, loud tapping noise from the left valve cover, sorta sounds like the timing chain might be a little loose? any common problems with this engine that could cause a really lean condition with similar noises??? any info appreciated, thanks....

 

A tapping noise from within the valve cover usually means that one of your lifters is sticking. About 90% of the time this can be cured by doing an engine flush to dissolve the deposits in the lifter.