Adjusting idle on 310 (1.6 Sigma)

[JonPivo]

Hello, I am after some help adjusting the idle on my 310R.  

My 7's idle seems to be on the low-side with the car often taking a bit of effort to start when cold and once going it doesn't maintain an even tick-over.  If I blip the throttle the engine almost stalls as the revs fall  (down to about 500 according to Easimap) before recovering and 'hunting' for bit before settling down a little (at around 800 to 860).  This also happens when driving, making the car tricky to drive in town.   

I can see various threads covering this topic but most seem to be for different models.  I have tried adjusting the throttle stop on the throttle body and increased the idle from about 800 to nearer 950 but the hunting was just as bad.  I would take it to an approved dealer to get it sorted but there is no dealer in Scotland currently...

Is anyone able to offer any advice?

Thanks,

Jon

[Graham Hutton]

Great question, I have the same problem and also no answer! Hopefully someone on here can help

[K7 VCT]

I have a 310 conversion on my 2014 car.

It was carried out by sevens and classics and the idle is perhaps a bit low, but it doesn't hunt much if atall and never stalls if revved.

Sounds like the map upgrade may be an issue perhaps?

[Tom_Arundel]

!. Don`t touch the throttle pedal when starting engine

2. Check for air leaks on manifold (pipes/plugs)

3. Disconnect, leave for a bit and then reconnect  battery to reset ecu

3. Possible lambda sensor failure...disconnect sensor plug under footwell and try driving without it connected (hunting)

Try these in sequence to see if it improves....generally works for me!

When you say `hunting` do you mean the engine speed changes by itself or do you mean the car `kangaroos` (jerky) when you try to accelerate/decelerate? `Kangarooing` can be throttle pot setting error and is not uncommon. If you have Easy map you can reset it but it is very sensitive and needs to be in balance with the idle air setting.

[JonPivo]

Thanks for the advice, Tom.  Following you're steps here's what I find...

1.  When cold I find the car won't start without a little bit of gas; it just turns over, almost catches but then stops.

2.  I can't see any obvious air leaks; I will have a more thorough check later this week.

3.  I have disconnected the battery for a bit so hopefully the ecu has reset ( any ideas how long this takes, i.e. is it pretty much instant or does it need no power for several minutes?).

4.  I will disconnect the lambda sensor when i go out next and see if there's any difference in behaviour. I thought this only had an impact once the engine is hot, so shouldn't be an issue at start up? On the the lambda sensor, how should this show up on easimap? I have to added it to my 'dashboard' but it always shows an error. Not sure if this is a real error, or because I have the wrong config file, or the ecu doesn't share this info? I also get an 'unknown error' coming from the ecu at all times, again I am not sure if this just because the ecu is locked or if it is a genuine issue.

By hunting, I mean the revs oscillate once the throttle is released, usually dropping down to a level where the engine almost stalls before recovering a bit and 'bouncing' around for a few seconds. This can cause 'kangarooing' if changing down, which is fun...more of a problem is when edging out of a junction, it is very easy to stall, usually at just the wrong moment! 

Finally, is anyone able to provide a bit more detail on the correct setting for the throttle pot for the 310, and a bit more info on how to adjust it? As you can probably tell I am quite new to all this, so please assume I know nothing!

Cheers,

[ChrisC]

Error from the Lambda sensor status, sounds like you have found your problem.

The Lambda sensor closed loop idle won't start until the Lambda timer has completed (30 seconds from memory) and the coolant is above 60c.  Each time the car is switched off and started again the lambda timer starts again.  So with a warm engine you only have to wait for the lambda timer, but a cold engine needs the coolant to warm up.  

You can look at the lambda voltage, which once working closed loop should oscillate, showing its controlling the fuelling.

only Error I have ever seen meant a replacement was needed.

beware of cheap alternatives and fake parts from eBay and Amazon.

[colindavies56]

what's your TPS reading on the easymap. with just the ignition turned on. 

[JonPivo]

Thanks Chris.  I had another play with Easimap to see what I could see with the lambda sensor - using the input template that easimap defaults to, I get no lambda panels and there is no input available to add. 

If I use a randomly selected one (9A6ae91.ec2) this does have some lambda outputs including warm-up timer that counts down from 20 seconds following start-up.  Once up to temperature the only lambda value that changes is 'Wide Range Lambda 1', measured in mA.  There is an additional panel available, labelled 'WR Lambda1 RI Error', which just shows a constant resistance value of 490 Ohms.

Is there a particular input template that I should be using?  Or is the fact no other outputs are available suggesting the probe is dead?

  

[JonPivo]

Hi Colin - TPS is 0.0 with just the ignition on.  Once started, with no pressure on the throttle, it mostly stays at zero with an occasional flicker to 0.4. 

[colindavies56]

my mate has the same model, oakmere set his at 0.38,before you alter anything take a photo of both easymap pages for a safety setting. set with just ignition on and it's easier as engine doesn't throb. 

[JonPivo]

I gave you the throttle site reading, the TPS (assume this what is labelled throttle angle increasing) is 0.41.

Do I adjust this by altering the throttle stop only? Or is there something else I should tweak?

[Tom_Arundel]

The TPS is driven by the throttle butterfly spindle so changes to the idle air setting/throttle stop affect the TPS readings. There are 2 basic settings on easymap   one is throttle position 0-15 and the other is voltage. 0.38v is about right (maybe a bit low) with a position setting just changing from 0-1. However.....the throttle stop/idle air may need adjusting for RPM and this will change the TPS setting which will need resetting and this will probably affect the RPM....YO!  There`s a lot of trial and error involved and the system is very sensitive to small changes I`m currently set at 0.4v and just on the edge of 0-1 position change which works for me!

Best to set it with a warm engine

Don`t overtighten the TPS screws.........It has been known to lock the throttle wide open !!!

 

[JonPivo]

Hi all,

Quick update on my car's idling issues...

After trying various things, I came to the conclusion it was probably a faulty lambda sensor (unplugging it made no difference to the way the engine ran).  Once we were allowed to visit England again, I took the car down to Oakmere who checked it over and replaced the sensor under warranty.  Engine is running well now - starts first time from cold and no more oscillating revs!

Thanks to all of you who gave advice.

Jon