Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Are there any direct or indirect scan tool indications for a bad PCV valve? (Stuck open / closed /just sluggish etc).
In particular - 2009 Honda Odyssey 3.5 liter.
operation is about the same across the board, it is to achieve a neutral state in the crankcase. if you want to make a tool you can use a map, 5v regulator and a volt meter, attached it to a old cap to get a reading. a example would be on a standard gm map ~2.2 would be good, +/- .3 would be a malfunction. there is more than just a pcv that could be at fault like a plugged pcv/vent hose or bad rings that could cause the fault. you should be able to find a issue with out a tool most times by pulling the cap, it should not be sucked in or pop out. there is some that fall out the norm tho, those would use a vacuum on the case and any leak would be a issue
Thanks for your replies. The engine is running fine. This all started when I took the car in for routine checks and they flagged the PCV valve as "clogged". I asked them if it was really clogged or is this just something they flag after time and mileage (118,000 km). After a heated discussion they admitted that it had not been checked but it was a time and mileage thing and the only way for them to get their "system" to put it on the report was to actually flag it as bad in some form or other. Apparently there is no method of putting an explanation along with the diagnosis.
Very poor "system" IMHO but I'm sure it makes them lots of money. Especially when the valve replacement is $189 ($48 being the valve). So this is why I wanted to know if it was actually bad or not. I was surprised they would take the time to pull it out, figure out that it was bad, and then turn around and put it back in without letting me know. It's easy enough to get at to test it myself. I was just wondering for interest sake if it would be identified on a scanner before i get the wrench out.
If the crankcase & valve covers aren't showing signs of excessive pressure or oil leaks the idle speed is okay with no problems on light acceleration it may well be fine.
A lot depends on oil change history modern fully synthetic oils especially the more expensive ester based ones keep the engine internals much cleaner than old style mineral oils. Also keeping the engine running in the proper temperature range helps prevent the formation of harmful tarry carbon and varnish deposits.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
It's funny you replied. I was only just thinking about my initial reply. I assumed it was stuck open but didn't even consider it being blocked.
Hope we were of some help. Like any mechanical part, it won't set a code itself, but may lead to other systems not operating properly and setting a code. It's up to the mechanics to desipher the data and work out what's wrong
