Mark1 Mr2 Revving issue help please

[Bernard80]

I have not had my mark1 mr2 for long now and I had noticed that on a cold start it up it sits revving a 2k rev but once warmed up goes back to normal, thought it might just be the qurck of an old car but then this morning it was actually revving itself, when I had the clutch depressed it was revving from 1k -3k revs, making quite a bit of noise, it did this for most of my commute everytime I stopped and depressed the clutch which being in a city at every traffic lights I was getting some looks looking I was just sat there revving the nuts off of it. Any idea what this might be, or is my car in fact an Autobot?

TIA

[cazzer]

Not knowin a lot about mark 1 mr2 engines this is going to be a tad vague but....

It will be a sensor of some decription more than likely.
Temp sensor sayin yer engine is cold perhaps.
MAF sensor (If it has one) registering too much airflow.

[Bernard80]

Bugger, was really hoping it was an Autobot

ETA, thanks though Caz will start looking into the sensors.

Edited by Bernard80 on Friday 18th June 16:23

[silent k]

Have a read of this http://www.mr2mk1club.com/choke.html - it's something to do with the choke. Mine does the same occasionally.

[Bernard80]

silent k said:

Have a read of this http://www.mr2mk1club.com/choke.html - it's something to do with the choke. Mine does the same occasionally.

Thanks for that link. Will have a proper read later.

[RobCrezz]

I think thats fairly normal, just running rich due to being cold.

[jcmr2]

Check water level, if it is low, the temp sensor will send a wrong message and the car will start hunting.

[Bernard80]

Cheers,

I have gone from a brand new car to a 22 year old car so am still getting used to all the unique things it does not had the problem since but hopefully the car is getting a good look over soon to see if it does have an issues.

[JollyGrnMonster]

jcmr2 said:

Check water level, if it is low, the temp sensor will send a wrong message and the car will start hunting.

what he said..

my thought on seeing subject.. ran one for 5years from nearly new and when the rad went the first thing that happened was it would blip the revs up and down on idle.. as the cold start does idle rather high and with the rad in the front and engine in the back when the water level drops the engine coolant temp sensor sees water, no water, water, no water etc and the ecu therefore is given water temp varying between hot and cold and ups idle and drops it again etc..

Fantastic cars!

Simon

[Bernard80]

Cheers definitly going to look at that at the weekend as its still doing it sometimes.

And yeah it does idle high on cold starts but been told thats normal.

[JollyGrnMonster]

agreed high on cold start is normal

[muckymotor]

Mine did this too and I was told it was normal for them. Don't they have a wax stat which is responsible for this?

[deviant]

Make sure you follow the coolant flush instructions properly, its quite easy to get an air lock in the system and not cure the idle issues.

[Bernard80]

Did the coolant flush (Well a good friend who knows much more abouts than I did and I watched, helped and got touch up paint all over my hands). It does seem to have stopped the idle hunting so far. The coolant was a very horrid yukky liquid rust colour. And well I am checking the coolant level in hopes of not getting an air lock in it.