Technical Revving while clutch in.

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Technical Revving while clutch in.

Rogo

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Chaps,

Just been driving my 2005 Punto, and noticed that while the car is driving, at any speed, if I put the clutch in, the revs jump around 1000rpm.

The problem isn't there when the car is stationary.

I've had a little look around on here and other forums, and one post point me towards a sticking throttle body. Does this sound possible?

I've noticed that when the car starts, initially coming out of 1st and 2nd gear, the car is very juddery when I'm accelerating hard, even if the clutch isn't pushed in. It does continue in the higher gears, but less noticeable.

Checked the fault codes, and all I've got is a misfire on cylinder 3, which I'm aware of, and just waiting for the leads to arrive to fix this.

While I'm here, when I'm looking into the engine bay, from left to right, do the cyclinders go;

4-3-2-1?

Thanks in advance for your help.
 
I thought cylinder 1 was the one by the timing belt (you won't see the belt, but you'll see the plastic cover, same side as the dipstick for oil). I think the cylinder numbers are supposed to be marked somewhere near where the coils are, so you could trace the HT leads back to double check.
 
I thought cylinder 1 was the one by the timing belt (you won't see the belt, but you'll see the plastic cover, same side as the dipstick for oil). I think the cylinder numbers are supposed to be marked somewhere near where the coils are, so you could trace the HT leads back to double check.


Yes in the punto's case Cyl1 is belt end cyl1 is coil pack end :)

Not all cars are like this tho! French aren't, there flywheel based cyl1, well it was on a stupid clio anyway

Do you have a 8v or 16v?

if its 8v, a gummed up throttle body yes - cheap and easy todo
16v, worth a clean, but its fly-by-wire, no cable, so it controlled by a motor via the ecu

Ziggy
 
The cylinders go 1,2,3,4 from the timing belt end. You're thinking of the "firing order" (you don't need to worry about that.)

Assuming you have 2 coil packs,
wasted_4.JPG
leads from 1 and 4 go to one coil, 2 and 3 to the other.

Again, assuming a throttle body with a cable, fluctuating idle is usually down to a vacuum leak (at the throttle body or closer to the engine) or to a dirty throttle body.
 
Chaps,

Just been driving my 2005 Punto, and noticed that while the car is driving, at any speed, if I put the clutch in, the revs jump around 1000rpm.

The problem isn't there when the car is stationary.

I've had a little look around on here and other forums, and one post point me towards a sticking throttle body. Does this sound possible?

I've noticed that when the car starts, initially coming out of 1st and 2nd gear, the car is very juddery when I'm accelerating hard, even if the clutch isn't pushed in. It does continue in the higher gears, but less noticeable.

Checked the fault codes, and all I've got is a misfire on cylinder 3, which I'm aware of, and just waiting for the leads to arrive to fix this.

While I'm here, when I'm looking into the engine bay, from left to right, do the cyclinders go;

4-3-2-1?

Thanks in advance for your help.

your seriously running the car with a missfire thats due to a faulty ht lead?
oh dear, no wonder these cars get a reputation for failed ecus:eek:
next.............
 
Yeah, you're right, I should just walk the 20 mile round trip to work, in winter, while I wait for the new HT lead to arrive.

Fingers, CMP, and Ziggy thanks for your helpful answers. I'll clean it up tomorrow.
 
Yeah, you're right, I should just walk the 20 mile round trip to work, in winter, while I wait for the new HT lead to arrive.

Fingers, CMP, and Ziggy thanks for your helpful answers. I'll clean it up tomorrow.

Im sorry, he is right. That wasted spark from the coil has to go somewhere and they normally spike back to the ecu. So the cost of a bus will be much cheaper then a new or secondhand ecu with new lockset...
 
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