I have recently had odd issues with the Seicento sporting I bought a little while ago. Runs OK, get some shopping, starts fine then I get low revs and runs like its not firing on all cylinders. Later starts fine, runs Ok. Sometimes corrects itself during the drive, sometimes doesn't. But its not there all the time. I thought it was when petrol was low but I have been running it on mostly full and issue still occurs here and there. Difficult to drive as it doesn't accelerate properly when its having a bad day. Any ideas?

SPI or MPi?

D

Its a Y plate if that helps I wouldn't have a clue

open the bonnet and count the injectors.

D

Now I have to find out what they look like to count them lol

OK I think I have 4 injectors at the back of the engine under the air filter, bit hard to see with that big blinking thing there. that will have to be changed lol

so, we are guessing at MPi.

There is a know problem with coil drivers in the micro ECU. This can be repaired.

Try and test which plugs are not sparking when its doing its rough running thing.

D

Thanks Rallycinq, is it an expensive fix for a garage to do.

Catching it running uneven in a place I can check it isn't going to be easy especially as it wants to stall when it does

I assume I check by removing the leads one at a time?

Numptey said:

I assume I check by removing the leads one at a time?

Click to expand...

yup

I'd use something insulated, unless you want some involuntary break dancing.

D

I have a teenager, will that do?

What am I looking out for?

Numptey said:

I have a teenager, will that do?

What am I looking out for?

Click to expand...

You have a teenager? Did you realise you can sell them for Medical Experimentation (they're not allowed to use animals anymore).

IF the ECU was at fault i'd expect the problem to be constant -intermittent usually signifies a bad connection. If you're lucky it will only be (the very common fault) a break in the insulation of the injector wires. Take off the air filter & when it's dark start the engine & wiggle the wires going to the injectors (as rallycinq noted use something non-conductive or wear thick rubber gloves unless you want to be fried!). The edges of your vision are more light sensitive than the centre of your eye so slowly move your head around -hopefully you'll spot a small blue spark. Repair any nicks in the wire with insulating tape -hey presto job done.

We are trying to rule out all the electrical faults.

Sparks are only useful when inside the engine.

If nothing is noted, the next step will be a compression test.

Cheers

D

I wanted to shock him into life, not sell him off lol

Taking off an air filter is something I can do and I will wiggle my head about to see if I catch a flash or spark. I will then try to remove the leads.

Compression testing isn't something I can do

Could be an intermittent faulty coil pack?

So far has only happened when I drive the car for a little while, stop briefly and start the car again. Sometimes corrects itself on drive home. Hasn't happened when starting from cold. As yet it hasn't happened when I have been in a position to check anything. Slight smell of fuel but that could be me accelerating more to keep it going and accelerate.

I do not know the car history apart from its not been maintained properly and has cost me too much already with new breaks and disks, new steering rack, rocker gasket etc.

I'm hoping to keep this long term so hopefully I can fix everything on it as it fails

It could be that the breather pipe is not connected, likely underneath the air filter, or has a split in it. This would also explain the smell of fuel (oil?).
East to check, and easy to replace if damaged.
Andrew

Thanks I have a few good starter points and just need the opportunity to check them. The breather pipe I should be able to do anytime.

Probably a good time to change the air filter while I'm at it, should I keep the whole thing standard or upgrade to something else as ive read standard is as good as anything else anyway?

I bought my Seicento nearly two years ago, and the standard air filter is a clean as new. I've never had to change it.
When checking the breather pipe for splits and for whether it is connected underneath the air filter, check that that there are no blockages, and clean it all out.
Andrew

I seem to be able to replicate the problem by leaving work 20 minute drive to the same shop, getting some shopping and upon starting the car it runs poorly. If I drive straight home it doesn't happen. Hopefully on Sunday I may get a few minutes to check for breather pipe issues and try to replicate it when it gets darker if that doesn't find anything

Does the beast only start hesitating once it's hot and has been parked for a while?

What about if you drive further than for 20 minutes without the parking/waiting part?

If it mis-behaves when it's had time to get properly warmed through, that might suggest a coil problem.


Ralf S.