Technical Ignition Coil and ECU

[fingers99]

£25 a set is a bit expensive. Rumour has it that NGK actually make the plugs for FIAT, so try the price for NGK (damn reliable firm, anyway).

If that gets you nowhere, try wiggling wires -- it may "just" be a wiring issue.

 

[gingel]

I bought the genuine fiat spark plugs.
Anyone know if the fiat part number for punto mk2b 1.2 8v (188A400) is 55188857 ?
On the plug it's written NGK and also FPT and the number 55188857.
And the model of the plug is DCPR7E N 10.
What is FPT? I thought it should be written "FIAT" .

Also, what should be the gap for that car?
The genuine plugs that i bought have a gap of about 0.95mm.

Thank you.

 

[Ziggy122]

I have a feeling th 8v have a 8mm gap but dont have haynes with me at the moment so dont tKe it as fact atm

Ziggy

 

[gingel]

My car is a 2006 model.
I found this from NGK website:
http://www.ngkpartfinder.co.uk/car_...TO%203%20%2807%2F03--%3E12%2F05%29&engine=1.2

According to this, from 10/04 –> 12/05 the correct spark plug for 188A4.000 is DCPR7E-N-10. It's also mentioned that the gap is preset.

Anyone know what the "FPT" on the genuine fiat plugs means?

Thank you.

 

[gingel]

Well, i replaced the spark plugs (btw the old ones also were DCPR7E-N-10),
and same problem.
So maybe it's ECU. I guess i will have to go to the garage.
One thing i noticed now, is when i connecting to the ECU with the ELM327 and
the MultiecuScan, there is a difference between "coil charge time" .
coil 1 is around 2ms and coil2 is around 4ms .
Are they supposed to be the same?

 

[fingers99]

Should be the same, but no idea what the tolerances are.

 

[gingel]

I checked again now (again, 2 cylinders are out), and coil 1 is around 2.3ms and coil 2 is around 2.87ms.

 

[texx]

Have been having Exactly the same problem,as i have 2 puntos both 04 3 door(the other running perfect) ive swapped coils, leads, and put new plugs in etc, Its also no2 coil thats not getting signal.Connector pins look fine,so im thinking its the main ECU thats the problem.So if it is I notice there is a code on the ecu 1aw5afp3 hw30319ba w34 being my one so does a replacement ecu have to have same number or are they interhangable as long as it 3door/5 door or same year??? etc.Any help appreciated before i visit ebay!

 

[gingel]

I took the car to the garage, and they said that the problem is the ECU.
BTW, my ECU model is also IAW 5AF P3 HW303 .

I think i will send the ECU for repair.

Thank you.

 

[Ziggy122]

Sending them off is the best option

Why? Plug and play
No worries abput immbo etc etc

Plus I think its cheaper to have it repaired then hace a repaired unit

Ziggy

 

[andre79ge]

Hello to all of you, I found this forum some years ago, when I still had my beautiful old FIAT Uno

Now I have a Punto MK2b 1.2 8v, with IAW 5AF ecu.

I have the same problem described in this discussion: engine runs with only 2 cylinders, P0351 error appears.

I think I identified the problem.
Inside the ECU there are the two coil output stages (power transistors), which tend to deteriorate, generating that issue.
I have no idea how to disconnect them (everything in that ECU is wire bonded). Did someone of you operate inside those ECUs?


Then I explain everything in the way I know it. Sorry for the English, I write from Italy and, unfortunately, here we are not used to read, speak in English other languages I just do my exercise reading some books in English and watching films in original language (with subtitles!!!).

In any case...
As far as I know, the P0351(2) is a common issue in IAW 5AF ecu. BUT it's generated by different reasons with respect to IAW 59F case.

In 5AF, it is often due to the output stage transistors of the spark coil circuitry.
Spark coils are connected to +Vbatt by a relais, which is always ON when engine runs (coils are always put to +Vcc).
Then the ECU drives the other side of the coil by putting it to ground (through a MOSFET or such a transistor): then, a current flows through the coil to generate the spark in the moment that the ECU stops putting the coil to ground.
The problem is in those transistors: they are no longer able to stand (to tolerate... I don't know the word to use!) to the coil current and so the ECU increases the charge time.
Basically, in normal conditions, current arises 3 - 4A in less than 2.5 milliseconds and with an oscilloscope, you could see that the zero voltage drive is really a zero voltage (or 0.2 - 0.3 volt, not higher).

When ECU output stage fails, you see that the zero voltage is no longer a zero (it goes to 1 volt, 2 volts and so on) and, consequently, the flowing current will be lower. ECU increases the charge time and, if the time needed to reach 4A is more than 4 ms (or maybe 5 ms, I don't remember), ECU sets the P0351 (P0352) errors and stops injecting to the two affected cylinders.

What we could do? Just change it with a new (or regenerated) one?

 

[Most Easterly Pandas]

Hello to all of you, I found this forum some years ago, when I still had my beautiful old FIAT Uno

Now I have a Punto MK2b 1.2 8v, with IAW 5AF ecu.

I have the same problem described in this discussion: engine runs with only 2 cylinders, P0351 error appears.

I think I identified the problem.
Inside the ECU there are the two coil output stages (power transistors), which tend to deteriorate, generating that issue.
I have no idea how to disconnect them (everything in that ECU is wire bonded). Did someone of you operate inside those ECUs?

Don't worry about you're English mate, you've made an attempt

I'm not fully clued up on the exact in's and out's of the ECU, but believe the part you're referring to may be the 'coil driver'?

I know that these do, like you say, sometimes break down and fail. Normally it's advisable to get an ECU specialist to repair this fault. This is what a Friend of mine done on his 2001/2002 Punto Mia from memory. Sent it away to a company, they repaired / replaced the coil driver, and then sent him the ECU back.

I hope this helps.

Jon.

 

[andre79ge]

yes, coil drivers!
They are transistor, inside the ECU and controlled by the ECU processor, which drive and control the current which flows into the primary coils of the coil pack. I will check for a company to fix the problem!

 

[varesecrazy]

Andre knows a LOT more about the innards of the ECU than I do - obviously..,

I would assume a Marelli repair is easier to obtain in Italy than the UK..??

Charlie

 

[s and b]

you cant repair these,what is possible sometimes is the wires on the output can sometimes be substituted by a new piece of wire but bear in mind these wires are thinner than a human hair and is the reason they fizout
be careful opening it up as if you do it hamfisted then you ruin the whole ecu
best thing is buy a s/h used one thats been virginised
ducatti motorbikes in your country might be able to offer a cheaper substitute for you OP

THE MAIN THING IS NO MATTER WHAT ANYONE TELLS YOU IS THE REASONS THESE BLOW IS POOR SERVICING WHERE THE SPARK PLUGS HAVE NEVER BEEN CHANGED this is irrespective of main dealer local independent or the guy working from a puddle stamping up the book of lies

these plugs should be changed at least 3 times in their life


they put undue strain on the system trying to jump a gap too big or nearly non existent
last example i saw was a week ago,car sold by us 33,000 miles only, split mint car 3 years ago ,came in missing on 2 cylinders and on 71,000 miles,this cars never had an oil change in this time never mind a plug change,took car off customer ,sold them a newer car for £15 worth of plugs,took them up the road and they commented how it pulled much smoother than their now faulty one so how much warning did it give before going pop
you couldn't make it up

 

[Most Easterly Pandas]

THE MAIN THING IS NO MATTER WHAT ANYONE TELLS YOU IS THE REASONS THESE BLOW IS POOR SERVICING WHERE THE SPARK PLUGS HAVE NEVER BEEN CHANGED this is irrespective of main dealer local independent or the guy working from a puddle stamping up the book of lies

So why are some models affected more than others, and why do they not all fail at similar mileages then

 

[s and b]

So why are some models affected more than others, and why do they not all fail at similar mileages then

early models to 02 had poor quality ecu fitted
all cars are driven different
cheap coils are worse than old oe spec working ones
spark plugs are the elixior of good health for anything engine
think about it

im reporting what i see


not what someone (a seller who insists coils are changed but will let you fit white box rubbish)who uses as a get out clause on ebay because their virginised scrapturd ecu with a polish is going to fail a week next monday

 

[andre79ge]

I answer here another time, just to let you know.

I bought a refitted/regenerated ECU and two brand new BERU coils.
It was a terrible idea!

First of all: I suspect they did NOT send me a IAW 5AF.P4, but they just sent me a mapped/modified 59F, with the software of the 5AF.

In any case: car runs very rough, it misfires at full throttle and has big idle problems (it runs good for 10 seconds and then starts to cough/misfires). Fuel smell at the outlet.

So they gave me a very bad ECU, probably they put inside the software and injection maps which is good for another car.

Furthermore: even if the engine misfires, the MIL does not flash. I guess they put inside the EURO2 software, which does not support misfire detection/analysis.

I will sent it back to the dealer and I will buy a new one (something like EUR 350 for a new ecu).

 

[atom0007]

Many problems on pcb scan be reworked if you have the right tools e.g. Smd rework station. Otherwise could be tricky.

Do you have a picture of the transistors you're trying to replace?

 

[s and b]

I answer here another time, just to let you know.

I bought a refitted/regenerated ECU and two brand new BERU coils.
It was a terrible idea!

First of all: I suspect they did NOT send me a IAW 5AF.P4, but they just sent me a mapped/modified 59F, with the software of the 5AF.

In any case: car runs very rough, it misfires at full throttle and has big idle problems (it runs good for 10 seconds and then starts to cough/misfires). Fuel smell at the outlet.

So they gave me a very bad ECU, probably they put inside the software and injection maps which is good for another car.

Furthermore: even if the engine misfires, the MIL does not flash. I guess they put inside the EURO2 software, which does not support misfire detection/analysis.

I will sent it back to the dealer and I will buy a new one (something like EUR 350 for a new ecu).

hi andre i think you have nailed it spot on here that they flashed the latter p3 software on to an m3
no it doesnt work, you may also find that this ecu is also not coded to the car aswell ie uit will work on any punto albeit badly as you have found