Technical 16v - startup & idle RPM

[Indiana Jones]

Hello!

I would like to get your opinion about my car's RPM.
It's a punto mk2b 2004, 16V engine with CVT gear box (fiat called it speedgear).

1. Unstable RPM for a few seconds after startup with cool engine.

• This only happens when the engine is cool down (off for at least 3 hours).
• Ambient temperature - the lowest it gets is 20 celsius (70 fahrenheit).
• The RPM jumps between 1000-1200 for a few seconds and then settles at 800 RPM.

I recorded this and uploaded to youtube (can't use a normal link because I'm new here, so please copy and paste the address to view the video):
youtu.be/uU7IZjVIptE

Any idea why this happens?

2. Idle RPM is 800. Is it normal?

Thanks!

 

[Jaka Cvajnar]

hey. first of i dont think its good to turn on the diesel engine the way u did, atlease here they tought us to first turn on the pannel/ aka the first key stroke, than wait for some of the light to go off than turn the engine on,

1.i have the same engine, i think i rimember my doing this one time to, but not for that long, never fixed it but dissapeared, maybe its the cold weather thats coming.

2. yeah 800 idle is normal, my is the same

 

[Indiana Jones]

diesel engine

Hey it's a petrol (gas) engine, not diesel.

 

[Jaka Cvajnar]

Hey it's a petrol (gas) engine, not diesel.

oh my bad though u had 1.3jtd.

well i still cant help u since i got this probly only onec and than dissapeared.

the idle is still fine i guess

 

[sandaru]

That is to feed the power hungry devices initially. After getting the signals from all ecus it decides the idle rpm. Switch on all the lights,demistifiers, heater at max, air con and see the increase of rpm and turning them all off you will see how it drops.

 

[judderbar]

Hello!

I would like to get your opinion about my car's RPM.
It's a punto mk2b 2004, 16V engine with CVT gear box (fiat called it speedgear).

1. Unstable RPM for a few seconds after startup with cool engine.

• This only happens when the engine is cool down (off for at least 3 hours).
• Ambient temperature - the lowest it gets is 20 celsius (70 fahrenheit).
• The RPM jumps between 1000-1200 for a few seconds and then settles at 800 RPM.

I recorded this and uploaded to youtube (can't use a normal link because I'm new here, so please copy and paste the address to view the video):
youtu.be/uU7IZjVIptE

Any idea why this happens?

2. Idle RPM is 800. Is it normal?

Thanks!

I have the same age car and engine. The car always starts like your car is doing but my revs are more stable. I don't get the jumping around.

 

[Indiana Jones]

OK so regarding question #1 on the first post, any ideas to why this happens? (Watch the video for full impression)
I was thinking maybe a bad/dirty sensor.

 

[flisko]

maybe dirty throttle body

 

[judderbar]

OK so regarding question #1 on the first post, any ideas to why this happens? (Watch the video for full impression)
I was thinking maybe a bad/dirty sensor.

Your temperature sensor is reading slightly on the gauge. The minimum temperature mine can read is 50C. Additionally I noticed on mine that when there is air in the coolant on startup it went a bit bonkers revving up to 2000 rpm in a scary way.

I also noticed yesterday that if the car is cold (normally in the garage) the revs wobble around sufficiently for the wife to ask me why the engine is doing that.