Legnum wont Idle

[Blackpoolchris]

Hi All My Legnum has been parked up in the garage all winter. It starts ok and runs on choke, but once i started to drive, it stalls all the time when i take my foot of the trottle. Any ideas way please. Thanks Chris

[Wobble]

boost leek ,stepper motor ,maf , fuel pump - maybe one of these

edit how does it drive when the throtle is down?

[foxdie]

You could also try resetting the ECU so it has to re-learn where to idle.

1. Disconnect the car battery negative terminal for 10-15 minutes, then reconnect it
2. With a cold engine, start the car and turn the aircon on full blast (fan to maximum, aircon on, temperature as low as it'll go)
3. Leave the car running like this for 20-25 minutes, do not touch the accelerator
4. After 20-25 mins or so, the car should be idling around 650 RPM when the aircon compressor isn't running and a little higher when it is
5. Turn the aircon off, the car should settle down to 650 RPM and stay there perfectly

Job done

[Blackpoolchris]

The Battery did go completly flat over the cold months, I charged it for about 2 weeks.

[Blackpoolchris]

Hi I Have tried this the car idles fine with heater fan on cold or hot as soon as i switch it off the idle dies. I have tried it on the road and same reults. any more idea's please

[foxdie]

You reset the ECU for 10 mins then definitely left the car running for 25 mins with the aircon on full cold before turning the aircon off?

Does it stall before you reach the end of this 25 min period, or does it stall as soon as you turn the aircon off?

[Blackpoolchris]

I may not have given it the full 25 mins.. It stalls when i turn the air con off.. If i drive it with the air con on the slowest fan setting it keeps running ticking over at about 900rpm

[bakerboy-2007]

Sounds like the stepper motor needs a clean
Just a 20 min job artical on here somewhere

My old car did the same thing after being stood for 2'weeks while we went on holiday

After cleaning do a ecu reset and should be fine , car does run a bit rough for first couple of hundred miles while it learns but will stop stallin

Good luck

[ianturbo]

I may be over your way tomorow if it's not pissin down , two heads better than one !
Ian

[Turbo_Steve]

Seconded - sounds like your idle control needs a good clean.
For best results, I'd suggest removing the throttle body, and from that removing the idle plate (be careful with the gasket) and clean out the huge amounts of crappy oil that's lurking in there - some of it will be thick and sticky like tar. Whilst it's open, it's worth cleaning out the various ports in the throttle body too.

You will have the stepper motor itself out. At this point, I would suggest a subtle modification to it:

I took a dremmel with a sanding tip to mine, and tapered the end a little more. This not only cleans off all the crud, but if there is a "dead spot" within the motor, it moves the idle point - the motor will no longer need to go to it's "dead spot" when trying to idle - it will be higher up the scale, as the bung is slightly smaller.

The ECU will re-learn this new stepper motor position for the same idle - it just means it tends to idle somewhat higher after an ECU reset.

[ianturbo]

As I said I am in blackpool tomorow , donor parts to see what's wrong !

[Blackpoolchris]

Hi Ian that would be great if you are. I have sent you a message with my mobile number

[ianturbo]

Pm replied , I'll give you a bell when I see the tower !!!
Ian

[ianturbo]

And it fixed it's self !!! Them japs know how to make a car !!!!
Ian