phantom257

hello all, over the course of the last year i have had this recurring problem which i thought was corrected until today. 4 times in the past i have had a very hard to duplicate issue. check engine would flash and not store a hard fault, only happened until 6500 rpm + running conditions pulling up a hill. started to find that the air filter came to be the cause just about each time being clogged by oil. car has been to the dealer many many times for this they are not rotary experts but are always making sure to check with mazda tech line.

some prior things to note:

2004 manual.
this is the mazda reman motor done before warranty was up.
BHR ignition installed
CAT is clear and been tested twice.
engine has 2000ish miles since motor replacement
blow by tube REMOVED when i add oil.

so here it is, 4 times (summer spring fall only) i have been going up a hill under a hard pull about 6500+ rpm and the power cuts cel flashes and i can not accelerate. i let off the gas let the car cruise under normal power a while cel stops flashing and car drives normal again most time even back about the 6-7k rpm again. each time in the past came to find airfilter was clogged in some way with oil on it each time accordion tube full, expansion box full etc. took it into dealer first 3 times no solution. 4rth time i cleaned it all instead and took it back. finally got the mazda engineer to suggest running the oil low as the new engine might not be the same oil level matching dipstick ( which i have seen as a tech on chevy and ford diesels for years.) as this sounded viable enough i have been running 1/2 lower on the dip stick since then and have had Zero issues until today.

today same run hot cobndions, started to accel around 6500 and cel flash, car cooled off later at home. oil in air filter etc... (only 300 miles on this filter). checked dipstick again its halfway from full more than 1/2inch that i have been doing.

so the solution i thought was golden has fallen apart, i will again have to take this in but i beg for help here. i have read all the oil in filter posts i could solutions for OVERFILLING should not apply here as i do not add oil with blow-by tube even attached to the neck EVERY TIME. what should i, or at least make the dealer check on this? as i am stumped and they are i could really use a technical answer here please.

kaseysdad14

Your best bet to keep the oil down would be to put a catch can on the breather. It will filter out the oil. There's a good debate over a sealed catch can vs a ventilated and so on and there's a few good diys. It will keep your upper intake manifold and filter clean. Also when you clean the manifold, be sure to clean the MAF. I'd still think that even with removing the breather it wouldn't be a bad idea to use a long funnel.

The flashing CEL is from a misfire. Get the oil out of your intake and see if having a proper air fuel ratio makes the misfire go away.

phantom257

so provided that i do remove the breather tube upon fill up i can still get oil in the intake without a catch-can?

i was under the impression it just catches oil from the fill up. yes the cleaning of all the items does include the maf, and yes until it happens again (filter clogging) i never get another cel until it happens again.

does the retrofit to the 07 style intake prevent this issue? i ordered all the parts mazda lists for an 07 for intake and tubes etc..

i do have a long skinny funnel i use sometimes, but it happened before even with that.

kaseysdad14

All the 07 breather changes is the location of the oil dumping. Instead of in that accordian it dumps it closer to your engine, I believe further back in the UIM. Getting rid of the oil is the best way to go. A catch can is relatively cheap and its simple to install. If all your worried about is liquid oil any can will work. They're on eBay for $30. If you want to get rid of the vaporized oil (you do) then a baffled catch can would be better. The oil condenses and falls out leaving clean air for your engine. If you know what you are doing some even have a return line to the oil pan and it becomes a zero maintenance item. Otherwise you just have to empty is every so often

04Green

iTrader: (1)

I have an 04, and a catch can. I set it all up so that the Air Jet feeds from the can, this means it pulls all the fumes. I also made the line from the oil fill go a tad up-hill before coming down.

You can also get a lot of oil shoved out the OMP check valve if it sticks. This may be your issue if things are recurring this often. That, or quit putting 8 quarts of oil in it ; ).

Vented catch can = vacuum leak, unless you only use the oil fill line. And, if you do that, car will stink a bit of oil and it will make a mess unless you figure out how to condense the vapors. The jet air line feeds from metered air. If you provide another path, it will really confuse the ECU when the engine is running leaner than it should based on the MAF.

phantom257

thanks guys, i think this gives me at least the clue i was looking for. i feel the car should not need a catch can no normal car should, as i have owned 14 cars and work on them for a living. that being said rotary is not my expertise so i defer to experts in the subject learning is good : ).

so ultimately it seems i need a catch can to prevent entering into the tube, but the underlying problem does exist of why. in the other threads i searched not many mention the issue and i think 04green your suggestion is the target of the next repair, or at least those valves that can stick. in the meantime I will look into the can. also there is no longer 8 qts i have been running 7-7.6 qts with WAY fewer incidents of this helped a lot.

thanks again for the help and i will post an update when i have one.