Hi, bit of a long post but not sure how best to explain.

My y reg punto's fuel injection warning light has started steadily flashing. I took it to the garage and the mechanic ran diagnostics and said the fuel ecu has developed a fault but that it won't affect the car at all. He tried to reset the light with the phonic relearn and another reset but both didn't work and it's still flashing.

I left the garage happy that it was okay but then noticed after reading around that it seems to be using fuel faster than normal. Now I'm not sure if to take it back and have him go over it properly, or get a second opinion from another garage. Or just to assume it's fine? I can't afford it to use more fuel than it does, and I can't afford to make the problem worse too I'd rather fix it.

The mechanic said the only fix is a new ECU which will be about £500. Is this true or is it worth checking the other parts of the system first? (Coil packs lambda sensor etc?) I'm not at all mechanically minded but I don't feel comfortable leaving it alone so any advice would be very helpful <3

Flashing ecu light is 1 of 2 things

Misfire detected

Or

Phlonic relearn programming needs completing

-----

How does the car run? Plenty of power still? Idling smoothly? No weird emissions / steam etc
Anything changed recently?
When was hts and plugs changed?
-----
My advise is if you have no history of plugs an leads
Then throw a set on

You can also try the phlonic relearn process yourself
Wait till engine is hot (fan kicks in twice)
Rev the engine upto 6000rpm and let it works it way down to idle
Repeat the rev'ing process 3x

Switch engine off an back on
Has ecu stopped flashing?

Ziggy

Ziggy

Did you mean to be talking about a flashing ECU light?

Original poster is talking about a flashing injection warning light.

judderbar said:

Ziggy

Did you mean to be talking about a flashing ECU light?

Original poster is talking about a flashing injection warning light.

Click to expand...

Y reg willbe mk2....
So itll be the eml
No injection light.....

Ziggy122 said:

Y reg willbe mk2....
So itll be the eml
No injection light.....

Click to expand...

Ziggy/Cocothela

Well I suppose a picture of the flashing light is going to settle it.

Cocothela

Perhaps a £500 ECU if you get a new one. A plug and play second hand unit costs about £100 pounds - just bolt it to the car and plug it in.

I've tried the phonic relearn and it didn't fix it.

I thought it was running okay but now I've noticed it seems to be using more fuel than usual, and juddery if I pull off slowly.

It had a service in July so I assume plugs were changed then. I'm not very car minded so I don't know haha I have it serviced yearly.

Is it easy to source a plug n go ecu? Can I convince the garage to do it? I'm clue less haha.

Thankyou for your help so far

I had another word with the garage to confirm his diagnosis. He said the code meant that the ecu needed a phonic wheel learn, but when we did it it didn't register. So he thinks it's needs a new ecu.

The phonic wheel learn did ask to be done about 1.5 years ago, but this was at the same time I had the power steering replaced, so I assumed it was to do with that. He said it should have no effect on fuel consumption, it would be the first time he had heard of the ecu affecting fuel consumption.

He thinks I should cut my losses and get a new car. He said there's no way of getting reconditioned ecu's either...

Its juddery when accelerating
So its missing.....

More diagnosis is needed
A
Power balance on the injectors wouldnt be a bad idea, but dont believe that

If its misfiring via duff plugs - and assuming it was done on last service is duff, as not every service gets plugs replaced

It may mean a phlonic relearn can successfully complete

Its odd for the car to suddenly need a relearn tho - not something that happens without a computer reset / diagnostic reset


Ziggy

It's more juddery at low speed if I lift off the accelerator and let it slow than when I accelerate.

Oil filter, air filter, and spark plugs were changed at the service.

It did do it once before but I thought that was because I had parts replaced...

Is it an idea to reset the ecu somehow? Or could it be a sensor? I find it hard to accept I'm going to have to replace the ecu it's done me so well

Also I've just gone out in the dark and little ring around the radio button is illuminated? Am I looking at an earthing issue too?

a phonic relearn is because---------------------
the cam sensor and crank sensor are out of phase
why is this?-----
because the timing belt is out of alignment,maybe stretched maybe jumped a tooth
if the ecu didnt flash this up then the ecu would be faulty but it did so it isnt

suggest you have the belt changed or at least confirm its within manufacturers parameters
remember if it is out and you do the phonic relearn of revving the mashers off it you could cause valve damage even though usually this engine is noon interference within reason
also if you say engine doing the stutter rap would also suggest timing out
a vacuum test under load and non load would help lots but i guess garages just like to plug stuff in these days rev the nuts off and breath in through their teeth when it dont work

get another opinion is my advice

Yeah I'm planning on getting it seen by another garage as I'm not convinced. I'm going to ask then to check a bunch of things for me. They probably won't like it but it's better than me trying to do it myself.

So far I'm now questioning the earth, the sensors, or the timing. Not sure on the fuel issue either, I put some in today so I'll be keeping an eye on it

I've got it booked into a garage for a weeks time, I'm slowly getting more sure it's an earth issue, it's always had weird electrical gremlins. I also checked under the bonnet today and the battery cable is a bit corroded. Will it be safe to use it and have it seen next week or should I get it seen again as a priority?

Cocothela said:

I've got it booked into a garage for a weeks time, I'm slowly getting more sure it's an earth issue, it's always had weird electrical gremlins. I also checked under the bonnet today and the battery cable is a bit corroded. Will it be safe to use it and have it seen next week or should I get it seen again as a priority?

Click to expand...

Its corroding where gearbox earth meets body and body to negative return?

They do corrode over time, easy fix with new crimped terminals or if you replace with predone wires

I took this photo this morning, this is my battery. The other photos are my dash tonight, and my radio light still on when my key is out, and radio is off. Weird right?

You can see the cursty goodness on the negative terminal!
That white stuff is corrosion

Whip the terminal off - get some like 180grit paper on the battery terminal and inside of the clamp - get it cleaned up and shiny

Clean the other earth thats bolted to the negative clamo too!!

If you them follow that thick negative cable down it goes to a 13mm bolt thats bolted to just under the battery tray - remove this also and give its surfaces a darn good clean up too!


Ziggy

So I took it to another garage today, and they've just called to say it's a specific fault code with the ecu. I asked them to check the cables and the earths and the receptionist has gone back to the mechanic to ask again if they did that. I'm annoyed that they're just reading the codes and not checking the things I've asked for...

He said the white stuff is white grease not corrosion. And that their fault is saying it's in the steering ecu. And that it's not communicating properly with the engine ecu. But it drives fine and apparently would pass another mot in this condition so I guess it's okay to just assume it's old...

Car dementia, forgets it can talk to itself poor thing

Cocothela said:

He said the white stuff is white grease not corrosion. And that their fault is saying it's in the steering ecu. And that it's not communicating properly with the engine ecu. But it drives fine and apparently would pass another mot in this condition so I guess it's okay to just assume it's old...

Car dementia, forgets it can talk to itself poor thing

Click to expand...

Struggling to see how that is white grease because you can see all the typical solid small parts of the same colour scattered on the battery