My car is sluggish one day, and speedy the next..?

Jlawson118

I'm new to driving, passed my test in May and got my car in August.

I got a 2011 Corsa Limited Edition and when I first took it for a test drive, it drove perfectly, even when I took it home it was amazing for a while. Then I don't remember when it started being sluggish, especially when I go from first to second gear it can be really jumpy. Sometimes I have to over-rev it just to get it to move and face being called a Boy Racer jokingly by my mum. Oe getting a lecture from my step dad about how I'm over revving it.

To speed up on the motorway, I have to move from fifth to third to rev up and get my speed back up, but sometimes in fifth it just starts slowing down, despite my foot being to the floor on the accelerator. And frankly after numerous issues we later found with the car, it's safe to say we were feeling very ripped off by JCT600. But that was to do with the wheels more than anything to do with the engine.

But then there's other days where it is very responsive. I just don't get it.. :rotfl: My grandad said his can be the same (he's got a 2014 Focus C-Max)

Is this normal?

fiish

Sudden loss of power suggests a problem with the car. If it's due for a service soon it's worth mentioning it to the garage when you bring it in.

I thought it might perhaps be your inexperience at clutch control but if you're having trouble cruising the motorway as well that's not it

A few questions to help us help you:
- What's the exact car model? (Engine, fuel type etc)
- Do any warning lights come on when the car is sluggish?
- How's the car's condition based on past services/MOTs? Any advisories or notes from the garage relating to the engine?
- What kind of journeys do you typically make with the car?
- Does it get sluggish only when cold, or in very cold weather?

Jlawson118

fiish wrote: »

Sudden loss of power suggests a problem with the car. If it's due for a service soon it's worth mentioning it to the garage when you bring it in.

I thought it might perhaps be your inexperience at clutch control but if you're having trouble cruising the motorway as well that's not it

A few questions to help us help you:
- What's the exact car model? (Engine, fuel type etc)
- Do any warning lights come on when the car is sluggish?
- How's the car's condition based on past services/MOTs? Any advisories or notes from the garage relating to the engine?
- What kind of journeys do you typically make with the car?
- Does it get sluggish only when cold, or in very cold weather?

My clutch control is pretty good I'll say, even when I took the car for a test drive in August, I hadn't drove a car since May and I didn't stall it once, I've only stalled it since August two or three times when parallel parking on my street :rotfl:
But yeah, on the motorway it'll be flat and well it just slows down, even in fifth gear..

- My car is a Vauxhall Corsa, Limited Edition, 2011 and a 1.2L petrol engine.
- There's no warning lights
- There's no history of anything in the service book, it's all passed. The only problem I found with it was a wheel issue, I took them into Kwik-Fit for re-balancing and the front drivers side wheel was warped inside, JCT600 refused to admit there was anything wrong with it, and then when I got the car home after they looked at it, they'd snuck another wheel on there.
-The journeys I usually make is to and from university, there's a lot of traffic and a lot of clutch control required sometimes. For early starts, I drive through this narrow country road, I don't really need to stop and start very often, and then later starts, and going home, I like to travel on the motorway, though going home I get stuck in a lot of traffic before getting on there.
- The silly thing is, I've found if I drive the car at night when it's colder, it runs faster. Yet I wonder if that's just because I've been by myself, no passengers or anything. But sometimes it can be sluggish or fast with passengers so I don't think it's weight.

I'm going to double check my service logs now actually

EDIT:
So I just checked them and the only work it's really had done was some new brake pads and a puncture repair at some point..
It's not due for a service until some point in the first quarter of next year. March I think

Lorian

Could be many things. One thing that instantly comes to mind though is does it pull OK on very dry days, and have problems on damper days?

If so check the ignition coil pack for cracks.

wgl2014

When was it last serviced?

I would suggest oil, oil filter, air filter and spark plug change if these have not been done recently. Also consider running some injector cleaner such as bg44k through.

The above are relatively cheap.

fiish

Another thing you could try, if you don't find other obvious problems (e.g. what Lorian suggested above) is to try running through 3-4 tanks of Shell V-Power or another branded premium petrol. What you're looking for from that is not the performance, but for the included additives to clean out your car's fuel system.

Sure, it will cost more than your usual fuel, but it's less than paying a mechanic to poke around the car.

Jlawson118

wgl2014 wrote: »

When was it last serviced?

I would suggest oil, oil filter, air filter and spark plug change if these have not been done recently. Also consider running some injector cleaner such as bg44k through.

The above are relatively cheap.

I'll definitely get looking into those, thanks a lot! I do run BP Ultimate through the tank sometimes to try and clean the injectors out. I was planning to run some through on the next fill up in the next few days

Jlawson118

fiish wrote: »

Another thing you could try, if you don't find other obvious problems (e.g. what Lorian suggested above) is to try running through 3-4 tanks of Shell V-Power or another branded premium petrol. What you're looking for from that is not the performance, but for the included additives to clean out your car's fuel system.

Sure, it will cost more than your usual fuel, but it's less than paying a mechanic to poke around the car.

Yeah I have been trying different fuels, especially to try and clean the injectors out, I've found BP Ultimate to be the best one actually. Shell V-power ran really nice when I put it in from 3/4 full of a tank already, but from nearly empty it didn't really like it. I've been planning to run through some BP Ultimate again on the next fill up even before the responses here, so even more of an excuse now to pay the extra for it

I haven't really ran it through for a few tanks though, would that perhaps work better then if I fill up with it around 3/4 times in a row before going back to regular unleaded?

Lorian

Lorian wrote: »

check the ignition coil pack for cracks.

I maintained a 1.2L Corsa for someone else for years. It only did short trips round town. it never needed injector cleaner and never ran on anything more than Tesco's petrol.....

Quite a pokey little 1.2L engine, fun to drive....

Jlawson118

Lorian wrote: »

I maintained a 1.2L Corsa for someone else for years. It only did short trips round town. it never needed injector cleaner and never ran on anything more than Tesco's petrol.....

Quite a pokey little 1.2L engine, fun to drive....

Well it'll keep me going for a few years I hope to get my no claims discount down at least :P

fiish

Jlawson118 wrote: »

Yeah I have been trying different fuels, especially to try and clean the injectors out, I've found BP Ultimate to be the best one actually. Shell V-power ran really nice when I put it in from 3/4 full of a tank already, but from nearly empty it didn't really like it. I've been planning to run through some BP Ultimate again on the next fill up even before the responses here, so even more of an excuse now to pay the extra for it

I haven't really ran it through for a few tanks though, would that perhaps work better then if I fill up with it around 3/4 times in a row before going back to regular unleaded?

Probably not much harm in trying!