Fluctuating idle/revs?? Please help....

[BadBadtz]

Hi All,

Just been out in the car and I have noticed that the revs seem to be a little unstable whilst at idle?? Sat in traffic and sometimes the revs will climb to about 1300rpm and then drop down to about 600rpm quite eratically?? I've never seen this before and its only just started doing it.

I think I noticed it whilst cruising with no gas on too. Doing maybe 3krpm and coasting in 4th it gets a little jerky sometimes??

The car still pulls well to the limiter, its just when the gas in not on.

Please help.

Cheers,
Nick

 

[drivebymonkey]

the automatic choke and the idle contol valve are the first places i would look.

then i would be stuck!!

 

[kingston]

i get similar though not irratic idle, starts off high then drops down to 6/800 at start up

Also get when slowing down in your in high gear/low speed, around the 3k mark it feels as if the wheels get tugged..

 

[corbie]

When was the last time you cleaned your Spoon Drop in air filter, if you are saying it didn’t used to do and started recently, could be that the filter is dirty.

Since you have a KPro why not do a datalog and see what is happening, as it could be a flat spot in the map?

 

[BadBadtz]

i get similar though not irratic idle, starts off high then drops down to 6/800 at start up

Also get when slowing down in your in high gear/low speed, around the 3k mark it feels as if the wheels get tugged..

That's normal when the engine is cold.

 

[BadBadtz]

When was the last time you cleaned your Spoon Drop in air filter, if you are saying it didn’t used to do and started recently, could be that the filter is dirty.

Since you have a KPro why not do a datalog and see what is happening, as it could be a flat spot in the map?

Unlikely to be that as its not been in there that long. My new CAI has just arrived so that will be going on this weekend.

The KPro is being remapped on the 6th April so I'll see what they find. Just odd that its only just started doing it??

 

[C&S Evo7]

You have a problem with the idle air control valve. located under the throttle body, this is a fairly common fault,

When the throttle butterfly is closed (i.e idling) the valve allows air to bypass the butterfly letting the car idle. As the load on the engine changes, alternator charging or fan switching on and off etc the air required to keep the engine running changes, the valve varies the amount of air required to make the idle as smooth as possible, when there is a problem with the valve the engine hunts at idle as it is unable to control the air accuratly.

It can be removed and cleaned which helps sometimes but unfortunatly the Iacv cannot be replaced individually (its not available from Honda as a part the whole throttle body has to be replaced. Most people would opt for a spoon as they use astd body and are cheaper than the one from honda.

 

[BadBadtz]

Thanks Simon! How difficult is it to remove and clean?

 

[C&S Evo7]

A bitch :? ,as the throttle body needs to come off then you can get at the IACV, you will need a new TB gasket from Honda. i think there maybe a post somewhere about removing it. i think wooty did this ages ago.

 

[BadBadtz]

A bitch :? ,as the throttle body needs to come off then you can get at the IACV, you will need a new TB gasket from Honda. i think there maybe a post somewhere about removing it. i think wooty did this ages ago.

Cheers mate. I'll do some searching around.

 

[pudski]

Having near enough the same problems with my car. But when the under bonnet temp is high(usualy after driving 9-10 miles) it seems to be ok.
idle air control valve? or heat related?

 

[MilanoChris]

Got the exact same happening to mine now. It's fine when driving about as long as the revs stay above 2000, car pulls fine, no power issues, though as soon as I'm in town in stop start sraffic the idle is all over the place. It's always hunting between 800 and 1400. Really fustrating.

Since I'm planning on a larger TB and the Hondata gasket is it safe to leave it how it is until I get one or the other or both?

 

[kingston]

have you tried putting some injector cleaner additive in with the petrol, when i spoke to tom about this issue he suggested trying that first before replacing valves and such - the issue has now gone away for me

 

[BadBadtz]

Hi Chris,

Mine cleared itself up after a long drive. Probably just the ICV getting gunked up.

 

[MilanoChris]

Hi Chris,

Mine cleared itself up after a long drive. Probably just the ICV getting gunked up.

Yep, mine's fine after the SW meet! Some long high revs periods seem to have cleared it!

 

[JT3173]

I get this along with a violent jerking when the engine is cold and I coast in a low gear. Once the engine is warm it clears itslef up and everything is fine.

 

[JT3173]

Re:

You have a problem with the idle air control valve. located under the throttle body, this is a fairly common fault,

When the throttle butterfly is closed (i.e idling) the valve allows air to bypass the butterfly letting the car idle. As the load on the engine changes, alternator charging or fan switching on and off etc the air required to keep the engine running changes, the valve varies the amount of air required to make the idle as smooth as possible, when there is a problem with the valve the engine hunts at idle as it is unable to control the air accuratly.

It can be removed and cleaned which helps sometimes but unfortunatly the Iacv cannot be replaced individually (its not available from Honda as a part the whole throttle body has to be replaced. Most people would opt for a spoon as they use astd body and are cheaper than the one from honda.

Cheers for the info on this Simon, I have the same issue, PM sent.

For anyone else that my have this issue I have found a good guide to taking the idle air control valve off on Club RSX.

http://forums.clubrsx.com/showthread.php?t=288936&highlight=idle+air+control+valve&page=1

:xcheers:

 

[jay82]

Re: Re:

You have a problem with the idle air control valve. located under the throttle body, this is a fairly common fault,

When the throttle butterfly is closed (i.e idling) the valve allows air to bypass the butterfly letting the car idle. As the load on the engine changes, alternator charging or fan switching on and off etc the air required to keep the engine running changes, the valve varies the amount of air required to make the idle as smooth as possible, when there is a problem with the valve the engine hunts at idle as it is unable to control the air accuratly.

It can be removed and cleaned which helps sometimes but unfortunatly the Iacv cannot be replaced individually (its not available from Honda as a part the whole throttle body has to be replaced. Most people would opt for a spoon as they use astd body and are cheaper than the one from honda.

Cheers for the info on this Simon, I have the same issue, PM sent.

For anyone else that my have this issue I have found a good guide to taking the idle air control valve off on Club RSX.

http://forums.clubrsx.com/showthread.php?t=288936&highlight=idle+air+control+valve&page=1

:xcheers:

i do have the same problem the last few months aswell and was just to about to put a post up today

 

[JT3173]

Re: Re:

You have a problem with the idle air control valve. located under the throttle body, this is a fairly common fault,

When the throttle butterfly is closed (i.e idling) the valve allows air to bypass the butterfly letting the car idle. As the load on the engine changes, alternator charging or fan switching on and off etc the air required to keep the engine running changes, the valve varies the amount of air required to make the idle as smooth as possible, when there is a problem with the valve the engine hunts at idle as it is unable to control the air accuratly.

It can be removed and cleaned which helps sometimes but unfortunatly the Iacv cannot be replaced individually (its not available from Honda as a part the whole throttle body has to be replaced. Most people would opt for a spoon as they use astd body and are cheaper than the one from honda.

Cheers for the info on this Simon, I have the same issue, PM sent.

For anyone else that my have this issue I have found a good guide to taking the idle air control valve off on Club RSX.

http://forums.clubrsx.com/showthread.php?t=288936&highlight=idle+air+control+valve&page=1

:xcheers:

i do have the same problem the last few months aswell and was just to about to put a post up today

Haha, beat you to it then didnt I :lol:

Still got to clean my Idle Air Control valve to make sure, after that if it still does not work then I think it will be a little remap

 

[jay82]

Re: Re:

Haha, beat you to it then didnt I :lol:

Still got to clean my Idle Air Control valve to make sure, after that if it still does not work then I think it will be a little remap

mines not really that bad but i'm putting the kpro in the car in july and want everything 100% in her