Engine wont start with PCV connected even after replacement

[Peage]

Hi Guys

I am having trouble with a V6 Mivec that I have been trying to get back on the road. The engine wont start with the PCV valve hooked up to the vacuum port near the injectors. Even if I start up the engine with the hose disconnected and then reconnect it stalls the engine. I have tried replacing the PCV valve but that hasnt solved the issue

From a cold start with the hose disconnected the engine starts and idles normally but but when it comes up to temperature it stops idling correctly (revs up and down) and once this starts to happen I am able to connect the hose and it doesn't stall the engine and it idles fine.

I have also had the stepper motor off to clean it up - although there wasnt much crap in there TBH. Would I be right in thinking I will need to buy a new stepper motor? Is there anything else I can try before buying one as I am seriously strapped for cash and this project has already eaten up more money than I would have liked. Thanks in advance!

Here is a video showing what happens when the hose is connected after a cold start....
From Youtube.com

[mivecmad27]

Sounds like a stepper motor prob,because of the vacuum bein disconnected it is allowing air into the engine unmeasured which explains the hunting,i'd say dis connecting any vacuum pipe would give you the symptoms you are experiencing,not just the PCV

[Peage]

Thanks for the response. I never actually tried it with another vac hose before I went and bought the PCV, stupid of me really!

So would you say it would be a safe bet that a replacement stepper motor would do the trick?

[mivecmad27]

Try start the engine from cold with everythin connected normally with the accelerator pedal slightly depressed,if the car starts and runs with you working the throttle then its 100% a stepper motor issue

[steelroe]

by any chance is the PCV turned the wrong way around

[Peage]

Dont think so, sure its the right way. I have plumped for the new stepper now as the engine would run with the throttle slightly open, as mivecmad sugeested to try. Will keep you posted!

[Peage]

Fitted the new stepper today and it has worked a treat Cheers for the help