Mitsubishi Lancer 98 choke races when cold

shabbycart · Postby **shabbycart** » October 18th, 2023, 3:31 pm

Hi all,

I have acquired an old lancer from my father inlaw.
1998 lancer GL with carbs. (1.3 or 1.5 haven't had a closer look yet - I'll have a look through the paperwork soon)

198,000 kms

Only issue I am having is that when it is cold it does idle very fast (Not sure on the rpm but I am estimating about 2000 at least, maybe more). Sounds like someone has their foot hard on the gas!
After it has warmed up, say 4-7 mins, then it slows down fairly quickly and idles perfectly.

How can this automatic choke be adjusted to start up at a lower rpm when cold? Does it have an adjustment?

Thanks

Postby **Dave** » October 18th, 2023, 3:52 pm

1998 GL is a 1.3 engine. The GLX is the 1.5.
Doesn't make a difference as the carburetor on the 1.3 or 1.5 is the same carburetor.

I would start with a service of the carburetor aka rebuild with fresh gaskets and seals.
Then you would know the condition of the automatic choke.

There was a Keystar rebuild kit back in the days..not sure if still available now.

shabbycart · Postby **shabbycart** » October 18th, 2023, 3:59 pm

Thanks.

It was rebuilt 2-3 yrs ago.
Runs perfectly from idle to full speed through the gears.

Just on cold start thought there may have been an adjustment to alter choke.

Had been modified some yrs ago when they added AC.

As I'm in Uruguay the kit won't be available here unfortunately.

If its just an adjustment of a component on the carb I'm hoping that would be a solution

Cheers

Postby **Dave** » October 18th, 2023, 4:24 pm

Yes there is a screw to hand turn and make mild adjustments. There is also an air screw which also can be used dependant upon your spark plug colour.

New carbs are available on eBay. Kits would be easy to spot. Can't miss that bottom gasket.

Good luck.

shabbycart · Postby **shabbycart** » October 18th, 2023, 4:36 pm

Dave wrote:Yes there is a screw to hand turn and make mild adjustments. There is also an air screw which also can be used dependant upon your spark plug colour.

Good luck.

Ah perfect.
Do you happen to have a diagram showing which screws to adjust to alter the choke cold limit?
Thanks

Postby **Dave** » October 18th, 2023, 4:42 pm

So it's a big screw that is turned by hand and it will depress a flat lever which is attached to the throttle plate. All mostly at the bottom of the carburetor.

shabbycart · Postby **shabbycart** » October 21st, 2023, 1:52 pm

I see the hot air intake pipe is missing. I assume this is quite important as it sucks in the hot air when starting and has some effect on the auto choke.
Any idea of the part number?
I don't suppose a rubber hose would resist the heat from the exhaust manifold

Postby **Dave** » October 21st, 2023, 2:18 pm

It's only required in cold climates.
Helps warm up quicker.
You can improvise there if you think the heating process would help with that hose back in place.
Part number lol....doubt you are getting that back to buy new.

shabbycart · Postby **shabbycart** » December 12th, 2023, 7:43 am

I understand this carb has an autochoke with a wax inside. Once warmed up by the coolant it relaxes the piston and slows the rpm down to a normal idle rate.

Now if the thermostat is faulty, i.e open then it will take much longer to warm up the coolant to melt the wax.
I want to eliminate that possibility first.

Also apparently there is an adjustment screw at the back to limit how much the auto choke opens.
I will experiment with this screw as the cold idle rpm is way to high until it heats up and settles to 750 ish.
I can see the piston open at cold and takes ages for the wax to melt and return the piston
https://forum.lowyat.net/topic/3404887/+2580