Help? SERVICE light coming on during idle.

I am having an issue with my 2009 GRiSO 1200 8v that has me puzzled. After idling for a while, the red dash light comes on with the !SERVICE notification, and this often accompanied by an engine stumble. After revving up the light goes off again and the engine runs smoothly. The diagnosis menu shows no codes (everything is at "0").

I thought this was a classic case of bad spark plug boots, and one of them did show a tear in it. I replaced with the NGK plugs and caps as described here: [You must be registered and logged in to see this link.]

But this did not solve the problem. Also, not sure if this is related, but when the engine is warm the idle is very high: around 1750 RPM.

Any ideas? Does it sound like an ignition issue, perhaps the plug wires or coils? Or something more serious?

Sounds like a combination of things but here's some thoughts based on my experience:

1. Pre-rollerisation (I saw your other thread !) my 2009 GRiSO had iregular idle 'stumble' that I could never figure or fix with tuning. It just felt like something hard was hitting something else hard inside the engine & dropped the revs for an instant. With hindsight I think it could have been caused when the metal surfaces (cam & flat tappets) were welding/interfering. It could also be just that the clearances were opening up too much but either way the whole 'stumble' went away after rollerisation
2. High idle could be badly tuned, could be frigged sacred screws, could be stepper, could be valve clearances OR could also be a combo of these. I've had 2,000 rpm high rev idle but cleaning TBs and retuning sorted that out; I still get the odd slightly higher than normal but it's liveable....one day I will try retuning idle with stepper out the circuit (I have fish tank valve in the inlet tube) and see if it will live without the stepper in use.
3. Do you get any codes on guzzidiag for the warning light ?. That could be a load of things ranging from lambda going out of range/wrong and throwing everything to ratsh*t; could also be oil gasket issue. If you ever fitted a Finebau unit or a lambda fooler you'll know all about o2 reading faults lighting up dash.

So I don't think it is anything to do with ignition; could be lambda and/or stepper issue (or rpm sensor) - especially if revving clears it; surprised you aren't getting fault codes; you need to rollerise. Soz to not be clear and others here likely can add more depth...

Yes, it has to be rollerised. Secondly I'd listen to what Paul is saying about some sort of sensor fooler, (Memjet, Finebau, Fat Duc or the like.) these all tend to over-tax the ECU's ability to trim and make it drop into 'Limp' mode which throws up a service warning and will cause a brief stumble when it occurs.

I'd check all the sensors, particularly the lambda sensor wiring to see if there is some shitty widget tucked up behind the starter motor.

Really though first order of business is to rollerise otherwise you're pissing in the wind.

Pete

Thanks, I guess I’ll see if it still happens after rollerization and deal with it then.

paulbrice wrote:

One day I will try retuning idle with stepper out the circuit (I have fish tank valve in the inlet tube) and see if it will live without the stepper in use.

Mine was tuned on a dyno (Lambda removed, power commander 5) with the stepper system closed, idle is always spot on, only use the stepper at realy cold starts as a choke. I installed a Briggs and Stratton fuel valve.

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You'll need to look at the stored codes. You get a code every time your get a SERVICE warning. I think the diagnosis menu only shows current active codes.

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Hmmm I checked all codes including “active” and “memo” and thy all show 0.

What about ECU errors?

All ECU and panel error codes show 0.

OK, I ordered the roller tappet kit! Ready for some fun installing it now.

Thanks for info Klaas because long term fixing it out the circuit means I don't have to buy a replacement plastic stepper (I've got old metal one) at €500+ euros

beetle wrote:

You'll need to look at the stored codes. You get a code every time your get a SERVICE warning. I think the diagnosis menu only shows current active codes.

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How can I look at the stored codes? I have just been using the diagnosis menu. Does it require a special device or is there another way to retrieve this information? (I have a generic OBD II code reader, not sure if that would work on this bike?)

You'll need Guzzidiag and Lonelec cables. Plug cables into the 'spud' under the seat and read out the stored codes using Guzzidiag.....full details are in the forum threads. Will also allow you to check and reset the TPS while you are at it.

Should have said you'll need a laptop to load guzzidiag on & to connect the cables - minor missing detail

Ah, makes sense. I’ll order the cables and get GuzziDiag going. I’ll need this to upload new maps after the rollerization is done anyway.

Yes, you'll need IAW5xReader & IAW5xwriter to do the maps. Let us all know what fault codes you get from that.

OK, Lonelec cables ordered from the UK. Thanks everyone for all the help and advice, this forum is a fantastic resource for a new GRiSO owner!