Engine revving like mad

fletch

In the mornings when I turn on my car, it revs to about 2,000 revs & does so for about 2 mins...I understand that the choke should come on to help a cold start but this seems ridiculous....I'm sittin at the top of my road at the traffic lights with the engine screamin, surely once the engine is up and running the choke should cut off quickly afterwards so as to save petrol?
What could be the problem/solution? Sticky choke? Engine needs tuning? I'm lost.

C_Breeze

thats normal , its just idling high coz its still cold.

once the engine is warmed up its should idle about 750rpm-1100rpm

fletch

C_Breeze wrote:

thats normal , its just idling high coz its still cold.

once the engine is warmed up its should idle about 750rpm-1100rpm

I woulda thought 1,500rpm would have been a more realistic figure...lately it's even been going up to 2,200rpm....after the two mins it drops to 1,500rpm and then a few mins later will idle at about 800rpm.....
It just doesn't sounds right with the engine screaming at 2,000 rpm.

kluivert

Mind does the exact same as that as well but to 1500rpm for exactly two minutes (I timed it...i was bored)....drops to 1000rpm then 800rpm.

Take it to the dealer to check the programming if your worried about it. Why dont you start your car in the morning and leave it for 5 mins and then get in and drive off. you ll notice a big difference compared to starting from cold and driving off.

Next time you start the car pull on the steering wheel so the hydralics will kick in straight away and then turn the key, sometimes when i do that the choke is really low.

I was told that by an Opel Mechanic

C_Breeze

well, mine idles abotu 1,800 when satrtin in the morning.

but i guess if your engine management system decides 2000rpm is what it needs it seems fine. as long as it idles normally after its warmed.

if it idles at 800rpm when warm id say you've nothing to worry about.

i know it may seem a bit strange you sittin at the lights in the mornin and your car revving like crazy , but i personally wouldnt worry about it .

theres always the thing in the engine (forgot wat its called) that you can move up or down to adjust the idle speed .

kluivert

Idle Speed Sensor or EGR Value?

freewing

had a similar problem a couple of years ago and the nice man from the AA told me there is a sensor in the fuel pump that pumps more fuel in when its cold but if it revs to high it needs a reset, usually its only a matter of unplugging it and then replugging it in . worked on mine

flanzer

Is it a VW Golf by any chance? This used to happen to me before I got rid of the car. It turned out to be the throttle body and needed replacing. It never revved right at all during a drive, particularly on idle

fletch

flanzer wrote:

Is it a VW Golf by any chance? This used to happen to me before I got rid of the car. It turned out to be the throttle body and needed replacing. It never revved right at all during a drive, particularly on idle

Ain't a VW Golf, its a Ford Escort...it revs fine once heated up, I just think 2,000+ revs is a bit excessive. Might go get it looked at.

AMurphy

Is it EFI or Carb.

if EFI, it may have a slightly faulty Engine temp sensor, so it think it is much colder than it actually is. Or there may be a temp controlled bypass valve on the throttle that is off a bit and needs replacing

If Carb, typically a bi-metallic strip spring is used to detect the temp, these can often be adjusted. And another possibility with the card setup is a collection of vacuum valves that operate in tandem with the choke system, and one of these may be faulty.

So either way, I'd look for a temp sensor or valve that is in the "choke" setup and that may be in need of replacement.

come to think of it mine revs up to close to 2000 on a very cold morning, but backs down within a few minutes. Fat, but not "screaming it's head off".

5500

kluivert wrote:

Why dont you start your car in the morning and leave it for 5 mins and then get in and drive off. you ll notice a big difference compared to starting from cold and driving off.

Is that not bad for the engine?For an uknown reason to me right now i always thought on a cold morning it was bad to leave the car ticking over untill it warmed up and that you were better off hopping in and driving

C_Breeze

eireal wrote:

Is that not bad for the engine?For an uknown reason to me right now i always thought on a cold morning it was bad to leave the car ticking over untill it warmed up and that you were better off hopping in and driving

ehh , its the other way around.

starting it up and driving off straight away is very bad, leaving it warm up a bit is good.

Litcagral

eireal wrote:

Is that not bad for the engine?For an uknown reason to me right now i always thought on a cold morning it was bad to leave the car ticking over untill it warmed up and that you were better off hopping in and driving

Yes, the engine will take longer to heat up when it's not 'working'. Most engine damage occurs when it is cold. It is better to drive away as soon as possible.

fletch

Litcagral wrote:

Yes, the engine will take longer to heat up when it's not 'working'. Most engine damage occurs when it is cold. It is better to drive away as soon as possible.

Thats what I tend to do...I leave the car pointing up the road so I get in and straight away pull off.....the car is EFI...

Litcagral

C_Breeze wrote:

ehh , its the other way around.

starting it up and driving off straight away is very bad, leaving it warm up a bit is good.

C_Breeze - It might be easier and more comfortable for the driver to do this - a warm engine is smoother, gear changes easier, better aceleration, warm interior etc. but it iactually increases wear and tear on the engine.:(

JohnCleary

Mine is like this... It's a Rover 214, 6 years old

When I start from cold, it revs to about 1.5k RPM for about 90 seconds, tappets kinda clicking as oil hasnt warmed up
It then lowers to about 800RPM, eventually levelling out at about 900RPM