when oil cap is off engine stalls !?!

bbjs006 · Post by **bbjs006** » September 16th, 2007, 9:45 pm

hey there i have a 96 mx3 precidia V6,
just changed my oil today getting ready for winter and as i was checking how much oil was in there i started the car to let it flow around and get a better reading of the amount in the car and it stalled. I thought it was weird and added more oil i thought it was just really low but even now after going for a long drive with it at normal level of oil and having it spread around it still does the same ( almost as if it were choking or not getting enough gas, the normal stall) , it is an odd problem i have never seen anything like it with any car no mater what the make .... any ideas would be very helpful ...

thanks
Jeremy

solo_ryder · Post by **solo_ryder** » September 16th, 2007, 10:14 pm

Ok, so let me get this straight, you are running the motor with the oil cap? No wonder it is stalling, put the cap back on! You can seriously mess up your motor if you do that.

Post by **Mooneggs** » September 17th, 2007, 9:34 am

yeah for real - put the cap back on!! lol of course the car stalls without the oil cap on

bbjs006 · Post by **bbjs006** » September 17th, 2007, 11:28 am

so you are telling that for a mx3 it is normal to stall without the oil cap ? after it happened to me, my friend said there was something wrong, i orginally thought it was the oil cap and that he forgot to put it back on, then he showed me, a 1988 firebird, 2005 dodge ram, 2003 mazda 3, all start and run without the oil cap and said that he once drove around for a week without the cap because it had broken so he ordered a new one and he had no problem with nothing on there. This would be something new for me and as long as it is normal for the mx3 to do that, then there is nothing wrong and i thank you for your help.

solo_ryder · Post by **solo_ryder** » September 17th, 2007, 12:14 pm

Ok, man you really need to put the oil cap on, the reason you need to is because we have a PVC system in our cars, that means that the heads have to pressurize in order for the car to run properly. I have NO idea why you would run the car with no cap, that is just not smart.

bbjs006 · Post by **bbjs006** » September 17th, 2007, 12:19 pm

great thanks i thought that there was a leak somewhere else and is was chocking itself or something like that ... i wasn't planning on running it without the cap it was just while i was adding oil that i wanted it to flow everywhere so i could get a better reading, but anyway thanks for your help much appreciated.

Jeremy

Dali · Post by **Dali** » September 17th, 2007, 1:01 pm

yah this will happen if the cap is off (confused me the first time as well), when checking your oil leave the car off and sit for a couple of minutes, use the dipstick because you will never tell from the top.

umcamara · Post by **umcamara** » September 17th, 2007, 1:53 pm

I don't understand how leaving the cap off would "help it flow everywhere".

nope-mx3 · Post by **nope-mx3** » September 17th, 2007, 2:17 pm

You never measure the oil right after the car has been run.
to get an accurate reading, it should be left for about 5 minutes, to let all the oil get into the oilpan (wich is where you measure the amount of oil).

So, you really should check the levels with the engine cold, since you put more oil in while running it because it died without the cap on.

You dont want too much oil in there either, not especially healthy for the engine.

-n

Post by **Mooneggs** » September 17th, 2007, 4:47 pm

even if you just remove the dipstick while the engine is running it will stall also because of the way it is designed.

Nd4SpdSe · Post by **Nd4SpdSe** » September 17th, 2007, 4:58 pm

Isn't it basically just a huge vacuum leak with the cap off?

Post by **Custommx3** » September 17th, 2007, 5:07 pm

Vanished · Post by **Vanished** » September 17th, 2007, 5:44 pm

BIG vacuum leak. If you look at your engine, there is a hose that runs from your front valve cover right to a T joint that goes to your air box. Its like disconnecting on of those hoses.

94mx3precidia · Post by **94mx3precidia** » September 17th, 2007, 7:05 pm

i can honestly say i never knew that! I wouldnt know cuz i dont drive around w/o my oil cap or dipstick but its good to know. Just goes to show that u learn something new everyday.

fieromx3 · Post by **fieromx3** » September 17th, 2007, 8:06 pm

on my ZE even with cap off and pcv off no matter what it runs the exact same with it on.. off or on it runs and idles perfect..