will not hold idle

[SUSS]

i have a problem.
the vn will not hold idle. it idles for about 2 -3 seconds then dies. You cant even rev it because it dies even quiker. Would anyone know what is the problem?

[VPWAGZ]

crank angle sensor behind the harmonic balancer

[SUSS]

crank angle sensor behind the harmonic balancer

thx mate,
wot am i looking at to replace one of these things? is it a easy job?

[VPWAGZ]

harmonic balancer pully has to come off.

take your fan shroud off and get a rattle gun onto the pully nut, once thats off use a pully to pull the balancer off then its just a case of undoing 2 bolts that holds the crank angle sensor in place, then unclip the wires.

install new sensor then wack it all back together, insuring balancer pully nut is tensioned to holden specs. also check the condition of the crank seal while your at it.


as for costing on a workshop to do the job i have no idea!! rough guide $300?

[SUSS]

ok changed that. got a brand new battery also.

gues what,,

stiill the same problem??

i changed the coil packs also...

any one know what it could be?

[Dayvo]

My old VN had the same sort of problem . I went to start it one morning and just as it was about to fire up i let go of the ignition key and it backfired thorough the throttle body and jammed the butterfly open and it would only idle for a second then cut out .
Worth a go at taking the intake pipe of at the throttle body and having a look .
Cheers ,Dave

[nathans1987]

fuel pump?

[SUSS]

thx dayvo il check it out tomorow morning.

nathan - i just put a bigger fuel tank in with new pump and everything and all that is working fine

[azkwazere]

ill assume you started with IAC Valve? Its sole resonsibility being to control idle....

aZk.

[SUSS]

ill assume you started with IAC Valve? Its sole resonsibility being to control idle....

aZk.

no i havent, could you explain iac valve? wots iac stand for? i know a little abit bout engines but im not that good.

thx azk

[azkwazere]

Ok.....

On your throttle body you have a valve, similar(yet extensivly differnt) to a choke on a carby.

Its purpose is to control air flow on idle...

Idle is where the engine is just running, no throttle action on the drivers aprt at all. With the throttle closed, no air should be able to enter the engine. As you know, without air, engines wont work. So you need to get air into the engine without throttle response from the driver.

The IAC, or Idle Air Control valve takes care of this job by monitoring and controling air intake at idle.. ie. it allows enough air to have the engine sit at around 750-1200 rpm (approx.)

If it fails to work properly, not enough or way to much air will enter engine and youll get super rev at idle or it will stall due to suffocation.

Normally, an engine's IAC is adaptive.. ie. it will vary its control to meet situation..cold morinings etc... hence when your idle may be at 1200 for a period then decrease by itself.

so, generally, an IAC can be fully reset buy an ECU reset, so lets start with that.

SOLUTION: Disconnect you negative battery terminal for 5mins, pump your break pedal and remove all your main engine fuses then put them back in.

When you start the engine after the reset, hold the engine at 3000rpm for 10secs to allow ECU to regain control and adjust settings.

aZk.

[SUSS]

solution completed - result nothing.the motor would just not start over.

its getting air , fuel, spark, im lost..

[dippa00]

If your getting good spark it sounds like maybe your injectors are not opening.
Sounds quite possible you have an ecu (computer) problem.

[vn calais manual]

sure u put another pump in. but is it actually working properly. id check ur fuel pressure.......