Very Low Vacuum (around 10in) - now low compression on one bank
I haven't really worried too much about the quality of the idle of my car, and sort of gave up and assumed "its just the way it is" for a long time now. Over the last year or so I've noticed that the brake pedal has become harder and that has lead me to notice that the vacuum at idle is lower than it used to be (its gone from about 13-14 at 800 rpm to about 10).
Its pretty steady at this level, I don't really seem to have any problems throughout the rpm range. I have advanced the initial timing as far as possible without pinging. I've played with the carb to get maximum vaccum but still havent made much progress. There are no vacuum leaks that I can determine.
When I crimp the PCV line while the engine is running there is an RPM (and also corresponding vacuum level) drop, and I can hear the valve click.
What sort of thing should I look at next? Compression? Valve timing? Stretched timing chain?
Thanks.
I haven't really worried too much about the quality of the idle of my car, and sort of gave up and assumed "its just the way it is" for a long time now. Over the last year or so I've noticed that the brake pedal has become harder and that has lead me to notice that the vacuum at idle is lower than it used to be (its gone from about 13-14 at 800 rpm to about 10).
Its pretty steady at this level, I don't really seem to have any problems throughout the rpm range. I have advanced the initial timing as far as possible without pinging. I've played with the carb to get maximum vaccum but still havent made much progress. There are no vacuum leaks that I can determine.
When I crimp the PCV line while the engine is running there is an RPM (and also corresponding vacuum level) drop, and I can hear the valve click.
What sort of thing should I look at next? Compression? Valve timing? Stretched timing chain?
Thanks.
?
