hi folks

Dont know if anyone can shed light on this problem.If i remove the oil cap when the engine is running the engine wants to stall.The car ticks over normally with the cap in place.I have cleaned and checked the pcv valves and all seems good.any help would be great.

Cheers trev.

Solved - Don’t remove the oil cap whilst the engine is running Trev! [emoji23]

Solved - Don’t remove the oil cap whilst the engine is running Trev! [emoji23]

 

:laugh::laugh:problem solved

hi folks.

checked a mates 300zx today and after removing his oil cap his engine does not drop to a stall.so i think something is not right with my engine.any help would be great.

trev.

From what I can read its normal Trev.

 

https://www.zcar.com/forum/10-70-83-tech-discussion-forum/292352-engine-starts-die-when-oil-cap-dipstick-removed.html

Does it ever pop the dip stick after a spirited drive?

No, Nothing like that - maybe it's just me being paranoid after I replaced the head gasket and was convinced something must be wrong!! Nothing ever goes smoothly and I can't recall it doing this before.

Its fine Trev, trust me :devil2:

Just read your post.

 

One of the main causes for this to happen is the missing restrictors that are unforeseen due to them hidden well inside the PCV rubber hoses and intake cam cover breather hoses. I've come across this on VG builds which are getting quite common these days, and "normally" I see these missing from the left bank PCV hose that meets the exhaust cam cover due to people just fiting 16mm hose without pushing the restrictor back inside the replacement hose. The other issue is, without these in place, it can also pull a heavy vacuum and drag oil into the plenum. But it can also push boost pressures into the crankcase if your PCV valves don't seal well. With the restrictors in place, it slows the chances down.

 

Here's a link that shows the restrictors.

 

https://www.z1motorsports.com/z1-products/z1-motorsports/z1-silicone-pcv-hose-kit-twin-turbo-p-3726.html

 

 

Maybe someone can explain this better, but it is easy to understand that without these, your engine will pull free flowing air straight into your plenum when you remove your oil filler cap or dipstick.

 

Hope this helps.

thanks for that information riccardo,new rubber hoses ordered.must have fallen out when i was rebuilding the engine

thanks again i will let you know how i get on when said parts arrive.

trev.