I unplugged EVAP solenoid, now it runs better ?

[VRTrickster 0]

I set out this weekend to sort out my on going lumpy idle, and cutting out. Before I set out to Egham to my Dads, to use his driveway services, I unplugged the EVAP solenoid valve.

 

The car didn't cut out, but did go to a couple of times and the idle was smoother ! It also started up better this morning, with none of the revs jumping up and down. Took it for a half hour run and it didn't cut out once, and idle was smoother, sitting a smidgen higher than before.

 

Before unplugging the valve the revs used to drop to a low idle and sort of creep up to norm idle. this was obviously if it never cut out, which it did rather a lot ! :x

 

Any ideas ?

 

Could it it be a dodgy valve or blocked canister ?

[VRTrickster 0]

It seems giving my car a vac leak seems to stop it cutting out. What would cause this to happen ?

[Taggart 0]

What's an EVAP solenoid valve?

 

How do give yourself a vac leak?

 

What canister are you talking aboot?

[VRTrickster 0]

The EVAP solenoid is a valve which controls the the petrol tank fumes going back into the inlet from the carbon filter canister, which sits under the air box.

 

If I pull the vac hose of the fuel reg it doesnt seem to stall, but if I plug the hose unconnected it does.

 

When I unplugged the solenoid whilst running hot, it didnt stall half as much, which is kind of a vac leak as it keeps the valve open rather than pulsed on idle. :?

[Critical_Mass 10]

Replied to on a thread regarding this- the valve at the top left of the engine block? Mine is missing completely.

[VRTrickster 0]

Critical_Mass, I think your possibly on about the black breather which attaches to the rocker cover to the intake pipe ?

[Critical_Mass 10]

Yeah mate. On some (most) VRs theres a round valve (PCV?) goes into the air intake pipe, mine is missing. Am i talking about a completely different valve?

 

Gaz

 

EDIT- sorry mate, misread what you said explaining (tired from stanford hall) what the valve did, i understand which valve youre talking about now, I thought the PCV did the job of dealing with the unburnt petrol fumes?

[VRTrickster 0]

No worries mate!

 

I think Ive had enough now with the cutting out that, I was considering going obd2 ! After reading Trigs posts it seems a bit to involved to carry out myself, and for the money it costs for parts and labour, I think Ill save up for a Emerald ECU !

 

Ive had enough :x

[Kevin Bacon 5]

Can't go wrong with a standalone mate, but if you think it will solve your idle problems.....wrong!! You've got to wire up an ISV to the standalone and program the PWM parameters. It's not a barrel of laughs! Or you can dump the ISV altogether and just hold your foot on the gas for 30 seconds when cold, which is essentially all the ISV does anyway.....

 

That might cure your problem actually, crack open the throttle stop a bit to give the ISV less work. If introducing an air leak smoothes the idle, either your ISV is knackered or there's not enough air getting in to maintain a smooth idle.

 

I warn you now though, even with a well setup standalone, no VR6 is ever dead smooth at idle like a BMW 6. You'll be chasing your tail trying to achieve that!

[VRTrickster 0]

Its not really the idle Im worried about, its the blasted cutting out that is really p*ssing me off :x

 

I think it could even be fuel related as it happens while cruising at low revs. When coming off the throttle at low speeds, it pops softly out of the exhaust, then the revs fall, and it just dies !

 

I was wondering if it was running lean on overrun and idle ? Is Vince able to change that part of the map when he remaps ?

 

I have changed the ISV for a new one, and also have a new MAF now, so theres not really anything else to replace!

 

I was going to check the cam timing again this weekend and replace the trigger wheel again, as I know I couldnt seem to get it spot on last time.

I know that the car was making 230 bhp on the rollers, so you would think the timing is ok, but Im getting desperate, lol!

 

Also what does the brass allen screw adjust on the ISV ?