[oregon_rider]

How many miles/km does the car have on it now?

What service has been done to the vehicle? Fuel filter? Air filter?

Have you used a good fuel additive/cleaner? It could be a sticky fuel pressure relief valve or a dirty injector.

Jeff

 

[kroelofs]

It has 47’000kms now. Just changed the fuel filter last night. I haven’t checked the air filter but other than that it’s all up to date. I use Lucas upper cylinder lubricant every now and then but it doesn’t make a difference in the startup.

 

[kroelofs]

How many miles/km does the car have on it now?

What service has been done to the vehicle? Fuel filter? Air filter?

Have you used a good fuel additive/cleaner? It could be a sticky fuel pressure relief valve or a dirty injector.

Jeff

I’m also still getting good fuel mileage (52+mpg) at highway speeds if that helps narrow it down.

 

[406]

Mine does it too. Has since I bought it new. 2-4 kind of lugs when it is first started. Since these puppies are electronic in terms of fuel/air control, I would think it is just a transient period while the ECM finds the correct parameters to dampen the engine to a smooth idle. Upon startup, the engine has to go from 0 rpm to some idle rpm (not 0). Ideally, this process would be critically damped, meaning the rpms don't overshoot and close in to the desired rpm (set point) as quickly as possible. Due to starting conditions usually never being the same (ambient temp, time since last shutdown, so on), the engine instead has a under-damped response where the rpms over shoot the set point, oscillate around the set point while being dampened to the set point.

Control systems.

Short answer, you're good my dude.

 

[kroelofs]

Mine does it too. Has since I bought it new. 2-4 kind of lugs when it is first started. Since these puppies are electronic in terms of fuel/air control, I would think it is just a transient period while the ECM finds the correct parameters to dampen the engine to a smooth idle. Upon startup, the engine has to go from 0 rpm to some idle rpm (not 0). Ideally, this process would be critically damped, meaning the rpms don't overshoot and close in to the desired rpm (set point) as quickly as possible. Due to starting conditions usually never being the same (ambient temp, time since last shutdown, so on), the engine instead has a under-damped response where the rpms over shoot the set point, oscillate around the set point while being dampened to the set point.

Control systems.

Short answer, you're good my dude.

I was leaning towards it just being the electronics figuring everything out, but thought I’d check with other owners. Thanks for the help.