Problem

[Ojc]

All things sorted with car Nova GSi engine BTW.

Anyway, it starts first time etc but idles very strange and revs don't drop properly, when you blip the throttle the revs up fine and then drops really slowly back down and eventually the engine cuts out.

Any suggestions?

[craig green]

idle valve or air leak maybe.

[Ojc]

Not idle control valve, had that off and cleaned it. Next stop is air flow meter?

[srs1]

i had same problem with my xe engine.
it was the airflow meter and also a open choke.
does it fuel ok or over fuel.

once i found a new afm it reved excessively, which was the open choke

[Ojc]

It fuels fine, sparks fine tis lovely jubbly apart from this problem at the moment.

Just to check, is there a flap inside the air flow meter that opens and closes when the car is started?

[Ojc]

Ttt

[craig green]

AFM has a flap to monitor air flow.

What acts as the choke on these engines is the idle control valve.

Are you confusing it with auxillary air device on the side of the inlet manifold?

Cg

[Ben]

I would say a split air pipe.

[Ojc]

How about a lack of petrol? Oh dear, I hope to god this is it :lol:

[Ojc]

Right, its not a lack of petrol.

Anyway, it drives absolutely fine, but when it comes to idiling its very rough and there is a lot of movement in the engine, its clearly over fueling as well as you can smell it and see a bit of black smoke out the back.

So, changed the air flow meter made no difference, also discovered this engine E16SE has not got a idle control valve? Just a coasting air valve, the TPS is fine and clicks, all four cylinders are firing and fueling (as it drives fine) its just when it comes to idiling its really coughing and spluttering.

Any suggestions as to what it could be?

[Stoo]

sounds very much like an AIR LEAK!!!!!!

How many people will it take to tell u!!

Split air hose, damaged gasket etc!! itll be after the AFM as well!

TRUST US!!

[johnny27]

check throughly any vacum pipes around the inlet end of things and the TB. A crack is most likely to come at the end of a pipe where it enters whatever its attached to. You'd be best removing the pipe from one end to check it.

[craig green]

Right, its not a lack of petrol.

its clearly over fueling as well as you can smell it and see a bit of black smoke out the back.

also discovered this engine E16SE has not got a idle control valve? Just a coasting air valve, the TPS is fine and clicks, all four cylinders are firing and fueling (as it drives fine) its just when it comes to idiling its really coughing and spluttering.


If there was a split induction hose, it would underfuel surely? The AFM will not register as much air as is being drawn in??

But it definately will idle like a dog ... I know from experience.

The E16SE should have an ICV, its mounted on the back edge of the cam box, kinda were a carb's fuel pump is sat. Perhaps a lack of one & its pipework is the problem?

Coasting air valve is on the dangling off the end of the inlet manifold, something else entirely.

Post some pics of the engine bay & back of the rocker cover area.

CG

[Ojc]

Craig, when you say it has a ICV, are you sure you not getting it confused with the secondary air valve which is located between the inlet manifold and the rocker cover? Does anyone have a pic of what they believe the ICV to look like?

Also in the Haynes manual there is no mention of a ICV for this engine?

[craig green]

Actually your right. Its not called ICV in the Haynes but its the same. if you have the thing as you mentioned then fair enuff.

Have you checked for holes in the induction tract? Any unmetered air that gets sucked in will cause it to run poorly.

CG

[Ojc]

The supplementary air valve is there, its strange though because when you unplug the electrical plug from it, it doesn't change the idling of the car at all, and doesn't throw up a engine management light, but if you unplug the Oil temp sensor that throws up a EML?

What is the job of the supplementary air valve? Anyone know?

Checked all hoses, no holes or split pipes, only one that looked like it could be doing with replacing was the rocker cover breather one.

[craig green]

What is the job of the supplementary air valve? Anyone know?

Checked all hoses, no holes or split pipes, only one that looked like it could be doing with replacing was the rocker cover breather one.

The supplemantary air valve works like an ICV. The engine monitors the idle speed via ECU & say when you switch on headlamps & rear heated screen, the load from alternator will slow the engine slightly & possibly make the idle lumpy, so the S.A D will open to let more inlet air in, by passing the throttle & making the engine idle quicker or more smoothly.

Agin the ECU will alter the SAD when cold started to idle quicker inline with the richer mixture the cold CTS has sensed.

Maybe change the breather hose & fit a new gauze in the rocker cover while youre there (pence).

CG

[Ojc]

Well the SAD is working fine, run 12 volts through it and it opens and closes fine.

Really at a loss to what this could be.

[craig green]

Have you removed the induction trunking from AFM to throttle 7 spread it apart to look for cracks & holes??

CG