Bad iding

[coolvxss]

My mum car seems to be idling bad. its a vn v6 series 2. she said when she starts it in the morning, it seems like its reving too much(like on older cars when you leave the choke on) but when she gets to the end of street, it nearly stalls because of low revs..

Her CAS was stuffed not too long ago, it use to not start when too hot. so took it to mechanic and got it replaced. It starts every time now, but sometimes when go for a drive to shop or someting, then come back and try start it, it wont start straight away. motor turns over for 5 seconds then starts, where as my vn starts in a second. And it just generally idles really rough lately.

[Not_An_Abba_Fan]

Could be a leaking injector. When it starts, does it puff out some black smoke?

[coolvxss]

Na pretty sure it doesnt. How would i tell if its leaking injectors? would i be able to see or smell fuel? and it sometimes starts fine, and sometimes doesnt?

[Not_An_Abba_Fan]

Generally the longer you leave it the harder it is to start as the fuel rail has completely depressurised and fuel has leaked into one cylinder.

Next time you go to start it, prime it a couple of times first, turn the key to on, then off, then on again, you will hear the fuel pump buzz, when it stops, start the car. If it starts immediately every time you do that, then it is either a leaking injector or a fuel regulator leak.

[aussieghostrider]

in the morning car idles high to warm up and its stalling at end of street cause its still cold ..give it a minute or so to warm up .. it is winter after all...

ok to the other problem of not liking to start when engines warmed up..

If I was you I would replace fuel filter , air filter , and run a botte of nulon total engine treatment at half a tank of premium fuel and go for a good drive ...

if that not help .. throttle body needs carbie clean treatment ,spark plugs/leads stuffed , or stuffed inlet manifold gasket ???

inlet manifolds are always a hidden problem with bad idle and stalling etc ... if you use a bit of coolant and you cant see a leak then inlet manifold gasket is always the problem ... you agree Abba ?

I gots to get my inlet gasket done soon .. lol

[mischa]

Next time you go to start it, prime it a couple of times first, turn the key to on, then off, then on again, you will hear the fuel pump buzz, when it stops, start the car. If it starts immediately every time you do that, then it is either a leaking injector or a fuel regulator leak.

Hmmm, my car takes some kickin over to get it started cold anless i do this, but fine when ive just been driving it. Could i have this problem?

[coolvxss]

in the morning after not being started the whole night, its starts fine. Just revs high for a while, then after driving few hundred meters and stop at end of street, feels like its going to stall. But has never actually stalled since the CAS got replaced. Is it possible the mechanic didnt fit the CAS right?

[89berlina]

Sounds like the CAS is fine or else it would be stalling completely and not starting for awhile. I dont think CAS have intermittent faults (correct me if Im wrong). They're either working or they're not. My Commodore has had similiar symptoms but Ive been able to fix all of it and its running beautifully. Here is a list of some things to check:

• Fuel filter - Definately a cause of making it hard to start. Cheap and easy to change, so if I was you I'd do it anyway to eliminate a potential issue.
• Injectors - May have a blocked or leaking injector. This is usually also linked to a dirty fuel filter. Easiest way to check this is to listen to each injector when the car is running using a screwdriver pressed up against the injector and your ear. You should hear each injector ticking and all should sound similiar. If one doesnt sound right, remove its electrical connection. If its working the car should run rough once you remove it. If not there wont be any change in the idle. Then you will know which injector to change. Best to change them all if this is the case.
• Fuel regulator - A way to check if this is working is to have the car idleing and remove the vaccum hose connected to the inlet manifold. You should notice that the engine revs pick up - if so its working fine. Something quick and easy to check.
• Coil pack - Try swapping it over with someone elses, if you know anyone with a VN. Also check that the coil pack has a good earth.
• Spark plugs and leads - Something thats quite easy to check if you have a manual. Test lead resistance and check spark plug gaps. If plugs are burning well, they should be a tan colour.

All I could think of for now...

Hope that helps

[Cheap6]

I'd be going with this "if that not help .. throttle body needs carbie clean treatment" to start with. It sounds like the IAC motor valve is sticking. I think there is a "How To" on it.

I prefer to avoid the carby clean (as much as possible - it does work really well) and use a rag soaked in kerosene or petrol to wipe the parts instead. I try to avoid the carby clean because it can wash th elubricant out of the throttle body bushes and IAC valve drive gear (and that most contain methanol which is pretty nasty to breathe in or with skin contact).

You really need to remove the throttle body and the IAC valve/motor to do a proper job too.

[aussieghostrider]

I have found if you use carbie cleaner it does remove lube from the IAC motor .. but using wd40 and an long plastic attachment you can spray wd40 in there and I alsy spray wd 40 in and around butteryfly whilst opneing and closing it ... when I would accelerate the thing would stick and revs would stay so car had automatic cruise control ...

[Chirpstr]

I had a similar issue with mine and in the end it was the fuel pump not holding pressure (but fine when running) and going back down into the tank. Like Fan Abba suggested flick the key on and off several times quickly so that the buzz goes on off on off on off and so on.....Then crank her over. If it starts then my money is more on the fuel pump rather than injectors,reg.

[Not_An_Abba_Fan]

The idle problem could be the IAC. Try cleaning it. Make sure the seal on the IAC is still good too.

It is sounding more like a vacuum leak though.

[ghog1726]

id say a vaccuum leak. id start checking the o2 sensor if it "feels" like its going to stall then doesn't (o2 sensor bolts into exhaust on passenger side headers - just unplug it and if problem does not change or barely does ur o2 sensor might be fkd/clogged/etc orrrrr check on the back of your throttle body about half way down there should be a little vacuum lead that goes across to your map sensor which sits on the firewall near the back of engine bay - its a little black bit of plastic with a power plug and a vacuum line, if the line is split or not connected it would cause the issues your having

[coolvxss]

Thanks guys. i will try some of this out on the weekend