[Teleost]

Hello everyone, I am new to posting in the forum and hoped to draw on the wealth of experience here. I am a non mechanic with some basic skills, unfortunately not extending to EFI systems. Anyways, I have a project 1985 drover high top which has undergone a thorough restoration this year. The old engine was replaced by my mechanic in Adelaide (I've since moved to Hobart) to a MK3 swift GTI engine (G13B). The engine ran great and was a welcomed boost to power, however, after driving it across 2 states its idle is now doing something annoying. It starts at its usual 900 rpm and scales to 1500 as usual when it's cold. Where it used to go back down to 900 it now hovers between 1700 and 2500, mostly it holds steady but occasionally it bumps up and down about 500 rpm.

I recalled this thing doing something similar with the carbeuretted engine and assumed it was the old carb acting up. The problem would happen after long road trips and then normalise after city driving.

I thought the problem may be from stirring up debris in the tank so I did a fuel filter swap today and this made no difference.

I've checked over the hoses and lines and these look like they're ok, and should be since they're new.


I am at a loss as to what may be causing the problem and was hoping somebody here who is more familiar with these engines might have a better idea of where to look next.

And if anyone knows a good Suzuki mechanic in Hobart, I wouldn't mind hearing about them!

Thanks for any help!

[nickireland1]

My mk2 gti sierra had a rhythmic up down idle once warmed up, turned out to be something called idle hunting caused by airlock in the coolant system. I just had to bleed it properly and its fixed completely.
There are other causes of idle hunting, search for it on redlinegti for all your gti related issues.

[Teleost]

Bang on, Nick! Turns out the coolant was a bit low and corrected when it was topped up! Problem fixed now.

[nickireland1]

Tripped me the f**k out when it first happened to me too haha