What's the usual cause of a lumpy idle?

Picked up the 2.0 and it's very nice. Only issues with it is a lumpy idle and no temp gauge.
I'll probably take the thermostat off my 1.6 as the car is using the fan when it gets hot.

Also where is the ECU as wasn't sure if it's got a 1.6 or 2.0 ECU in it which could be the idle issue (running lean maybe)

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1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

look up in the passenger side footwell and u shud be able to see the ecu code

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Cool will do tomorrow and post it

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1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

ur lumpy idle problem is probly a fooked temp sensor as this affects fueling and u say ur temp gauge isnt working, hope this helps

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Ah cool, where is that situated on the car?

The fan is coming on and cooling it all and I have the part to hand if I can find it on my car

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1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

its on the thermostat housing but if the fan is coming on then i dont think it will be that. wen was it last serviced do u know?

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Maybe its cammed.

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Well I'll change that anyway can't hurt
Not sure when last serviced but went through it's mot in December.

Cammed?

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1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

Nevemind appears the MAF was crap. Unplugged it and its idle was fine.
Will take the MAF off of my other si with the filter tomorrow and try that

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1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

could be the temp gauge sender which is located under the thermostat remove the top rad hose and you will see it the top one is the temp sensor and the only way to tell if its cammed is whip the rocker cover off and take a look at the code on the end of the cams

she's figured out its the MAF already..

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Well I cleaned up the current MAF and changed over to my k&n.
It's running a bit better but it's still lumpy but rather them idle if 500-600rpm and almost stalling it's starts steady at 1500rpm then dips and goes up and down between 900-1000rpm so it'll do until I can replace it

_________________
1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

_________________
1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

ooooh new bits any plans you wanna share

Rad and fan are up next so I can change the thermostat etc then.
Also going to give the coolant holder a clean up

The maf in the boot that's a 1.6 one isn't it?
It appears to be identical to the one off of my old car.

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1 way to sum up the 197 is like sex, you build upto the best bit and when it eventually happens it only last a few seconds but you always want to do it again!
Poor Orange Si is hurt. Started first time after sitting for 3 weeks and with virtually no petrol in it

yeah i think it is

just leave the maf off, my mk2 runs fine with out it

but as said if youve got a 2.0 ecu, injectors etc, then a 1.6 maf will make it run like a bag of shite!

but as said it could also be the temp sensor on top of the stat or a timing issue

did you find out what ecu its running?

pretty sure its 2ltr ecu but not 100%

DEEP, DESK or DEWY is what you need