No acceleration from cold.

[Dean0o0o.]

Got a slight issue with a 172 cup...

Whenever I start the car from cold there doesnt seem to be much go up until about 3k RPM. There just seems to be alot of travel in the pedal. The car will just idle along at a rolling speed, but as I push the pedal nothing happens. Then when the revs get upto around 3k it just kicks all of a sudden.

Once the car is a bit warmer it seems to run fine... when I push the pedal it accelerates.

It may be a safety feature of the car like my Megane F1 had a low rev limiter when cold? im not sure.

Cheers for any help.

 

[MikeoftheQuays]

Sounds a bit worse than most but these engines are notorious for running crap when cold.

Mine is a whiny, lumpy, hesitant piece of junk for a minute or so then it perks up.

 

[sideways danny]

sounds like it might be lambda related,

 

[Toms_clio]

Tbh when it's cold you should go above 3000 until it's warmed up. Where in stortford do you live?

 

[Dean0o0o.]

sounds like it might be lambda related,

Cheers Danny, should be up your place in a month or so. Just having to get my wheels refurbed so had to delay the manifolds!

Tbh when it's cold you should go above 3000 until it's warmed up. Where in stortford do you live?

I know I shouldnt, but still the car should do as its told! Just hoping this doesnt relate to any major issues I could come accross in the future.

I live in Stotfold, not stortford. But im regularly in stortford as my family are there.

 

[montana]

they are limited by the ECU when cold, sometimes mine runs like a kangaroo other times its fine

However yours sounds a bit more serious than that if you literally have no go!

 

[jimjim150]

Yeah, as above - you sure it's not the "I'm cold. You're hurting me" limiter doing its job?

 

[Dean0o0o.]

I didnt actually know of such limiter? I just noticed it one day to be honest. Since then I just idle along until it gets warm. But it is a kangaroo effect...

It will literally pick up to around 5mph, then stop accelerating until you use alot more revs.

Could this be a potentiometer fault?

 

[jimjim150]

Hmm, didn't read through it properly before - does sound more like a sensor issue if it's kangarooing like that.

 

[Dean0o0o.]

had a fault code appear today... managed to read it on my android app and says problem with catalyst emissions threshold reached. Do you work weekends Danny?

 

[Russ_16v]

The 'cold' limiter is 6500 rpm so its not that.

They do run lumpy from cold and can give a little 'stutter' as it clears its throat, but with that fault code it points towards the front lambda probe

 

[sideways danny]

had a fault code appear today... managed to read it on my android app and says problem with catalyst emissions threshold reached. Do you work weekends Danny?

I do mostly, but not this week. Call me tomorrow

 

[S76Pilot]

Pre cat lambda sensor. Change it. Bet you problem goes away. Had exactly same prob on my 182.

 

[Gardus]

Same here. Also, the onboard computer show a very worse MPG in those first few minutes.
Keep a constant throttle in those conditions and after a while the car will suddenly starts accelerating.

 

[Iain C]

Same here. Also, the onboard computer show a very worse MPG in those first few minutes.
Keep a constant throttle in those conditions and after a while the car will suddenly starts accelerating.

Erm it will have poor mpg as its running "choke" (rich, what ever you like to call it). :S

 

[Gardus]

Yes, I know.

 

[olliewebbuk]

Erm it will have poor mpg as its running "choke" (rich, what ever you like to call it). :S

No such thing as a choke on a modern car, just a fast idle.

 

[Gardus]

It's not called choke but it's true that the ECU constantly changes the air-fuel ratio, so it's sort of a choke function to protect the engine when cold!