Power issues when starting car then driving?

[mrcactus]

title - power issues when starting car and setting off first thing


Apologies if this is posted in the wrong area. I have a 197 sport (2009) - This is my first sport car and I am so inexperienced it's unreal.



I've noticed that when I start my car in the morning (cold winter, or warm summer) it idles higher than it used to, around 1.5k rpm. If I sit there for 5 minutes it will drop below 1k rpm. If I don't sit there and just start the car up and drive, it feels like the car has little power or the will to accelerate....it almost feels like I'm in the wrong gear and its struggling, despite being in 1st gear.



When I get out of the street and onto the main road, I try to accelerate and it feels the same. Its really hard to explain sorry. If I am on the A road, when I;m in 6th gear going 70, it will happily pull/pick up speed if I accelerate.



Some other info that may help describe my problem: it starts to backfire when I slow down considerably and down shift a gear (sounds nice though). Sometimes it has popped on a gear change from 3rd to 4th



I'm worried that I've done some damage with driving with little to no coolant. Any advice on how to proceed? I'm too afraid to drive it encase there is an issue and me driving it causes real problems. Thanks for any help or answers

 

[RSRowe]

Sounds normal to me.

The revving up at start up is to warm the catalytic converter up. But generally speaking, they run like crap when cold. Some are better than others.

 

[Marsch]

Like RSRowe said the revving up is normal when it was parked for a certain period but it shouldn't take 5 mins. More like a half or one. That's at least the case for mine.

If you don't let it warm up and start driving right away it can be hesitant with acceleration and also start to "kangaroo".

Besides that removing one or or both cats and/or running an aftermarket exhaust can excerbate the issue with the acceleration at lower rpms. In this case it's maybe necessary to have the flat-spot mapped out.

That it pops under certain conditions is also normal and also depending on what mods you're running.

That said if you noticed the behaviour changes just now and it wasn't like that before then you better take it to an expert that can plug it in to see if it's throwing any codes and have it diagnosed in generel.

My 2 layman cents.

 

[R20BTG]

Where does the low coolant come into this? Have you driven it with low coolant?

The cold start things sounds normal, in summary:

- Your car’s fuelling is controlled by a map (tune) which has all sorts of parameters that control how much fuel and air to allow.
- This map takes into consideration variables such as air temperature, throttle position, timing, engine load etc.
- The factory map from Renault has been designed to operate at a wide range of variables and meet emissions targets.
- it is normal for a ‘cold start’ to feel a bit lumpy and the idle to be a bit higher until some of the operating parameters are met, it might then drive normally.

Us old farts will remember the days before electronic fuel injection and having to control the fuel mixture and idle with a manual choke.

 

[youngarthur]

Manual choke?. I remember the time when you fed it a bag of Hay, before it would move, upkeep was very expensive, it needed new shoes every few weeks. I remember when....o shut up Arthur!.

 

[mrcactus]

Thanks for all your replies guys! I have taken it to several mechanics who can't seem to see what the problem is. R20BTG - Yes, I did drive it with little to no coolant but not sure for how long before I realised there was nothing/little left, which is why I'm concerned I have done damage.

Few weeks ago, I had the timing belt and pump done. Already had the aux belt done. Recently had the spark plugs changed as the mechanic I took it to plugged his computer in to it and it didn't throw up any codes/error messages etc. They kept it for the day and tested the car when the engine was completely cold and that's when they told me they had diagnosed it as dodgy or old spark plugs.

I must admit, it is a little better but after it being sat for 8 hours yesterday while I was in work, it still wasn't good when I started it up and drove right away. As Marsch said, it kind of kangaroos a bit when I attempt this.

I've also noticed that when I am in 6th gear doing 50mph or over, the car feels ever so slightly like its vibrating. Again, I'm worried I did damage with regards to the coolant (or lack of) problem.

 

[Foxspeed]

check live data on the lambda sensor see if its working correctly ie voltages fluctuating a lot/quickly