Fiat 500 Misfire ECU Repair

fiat 500 ecu, fiat 500 misfire, fiat 500 ecu repair

This Fiat 500 engine ECU will cause engine misfires across one or more cylinder after driving over 40mph/64kph. When the ECU becomes faulty the engine will be forced into limp mode, significantly reducing power and the engine warning light will flash.


When diagnosing this Fiat 500 misfire, fault codes will be found for misfire detection across multiple cylinders. You may be able to clear these faults by cycling the ignition off and on again, or via scan tools but the fault will return as soon as the vehicle gets back up to speed.


You may seek to resolve this problem by purchasing an expensive replacement from the manufacturer. However not only will this need coding at an extra expense and only come with a short one year warranty, but it will be prone to fail in the same manner. The manufacturing defect has not yet been rectified at factory level, meaning all replacements will fail at some point.


We offer test and rebuild of this Fiat 500 ECU, our in-house team will engineer-out the cause of these problems so that it will not fail again. We will rebuild within 2-3 working days and return you ECU with an unlimited mile lifetime warranty.


Common Failure symptoms:

  • Misfire
  • Limp mode
  • Flashing engine warning light


Common fault codes:

  • P0301 – Cylinder 1 Misfire Detected
  • P0302 – Cylinder 2 Misfire Detected
  • P0303 – Cylinder 3 Misfire Detected
  • P0304 – Cylinder 4 Misfire Detected
  • P0300 – Random / Multiple Cylinder Misfire Detected


How to diagnose:



Magneti Marelli IAW 5SF


  • IAW 5SF8.K2
  • IAW 5SF.M9
  • IAW 5SF9.A2
  • IAW 5SF4.L9


Fiat vehicles that were built between 2005, at the earliest, and 2017 will have this engine ECU that suffers from common failures, additionally it will also experience the fault codes:


  • P0351 – Ignition Coil A Primary/Secondary Circuit Malfunction
  • P0352 – Ignition Coil B Primary/Secondary Circuit Malfunction
  • P0353 – Ignition Coil C Primary/Secondary Circuit Malfunction
  • P0354 – Ignition Coil D Primary/Secondary Circuit Malfunction


If you have one of the following Fiat models, and suspect a faulty ECU, we can test and rebuild your Fiat ECU within 2-3 working days.



Magneti Marelli FPT 9GF


  • 9GF.T4
  • 9GF.DK
  • 9GF.N1
  • 9GF.T7


If you own a Fiat vehicle manufactured between 2007 to 2021, and are suffering from random misfires, the vehicle going into limp mode, and a flashing engine warning light, you are likely having an ECU failure.



Bosch ME17.3.0

Commonly failing part numbers:

  • 0261S17572 / 55275939
  • 0261S21008 / 46341569 
  • 0261S15048 / 55274450


Fiat 500 misfires in models built between 2016 to 2022 are caused by this faulty engine ECU, we can rebuild your Fiat 500 ECU, and any other Fiat vehicle with this type of engine ECU fitted within 2-3 working days.



Test and rebuild:

Each Fiat 500 ECU we receive is thoroughly tested on our custom-built Hardware in the Loop testing rigs, designed to mimic real loads and conditions of the road. If the unit is identified as faulty, our technicians will replace all defective parts with components that are of a higher quality than standard.



All programming is retained in our rebuilding process, just simply plug and play when you receive the ECU back.



Our strict quality assurance process means that our defect rate is lower than 0.49%, guaranteed by our unlimited lifetime mileage warranty. This is why major franchise dealerships around the world trust us at their primary service provider for high-quality remanufacturing solutions.



Lifetime unlimited mileage*


How do I get my unit rebuilt?

To pay for the rebuild click the Shop Now link above, select your part number and click: Get yours rebuilt.

Print the payment/booking confirmation email.

Package the Fiat 500 ECU inside a sturdy box with plenty of packaging material (make sure you include your confirmation email in the box).

Send us your package by tracked courier (the shipping instructions are on the confirmation email).

Once received we will test, rebuild and return your ECU with an unlimited mileage lifetime warranty. (if your unit turns out not to be faulty then we will refund your payment less a small testing fee and return shipping)


What if I don’t want to pay up front?

This is not a problem, if you prefer this option then follow the following steps:

Fill in and submit this test form.

Print the booking confirmation email.

Package the Fiat 500 ECU inside a sturdy box with plenty of packaging material (make sure you include your confirmation email in the box).

Send us your package by tracked courier (the shipping instructions are on the confirmation email).

Once received, we will test your unit and call you to advise on the outcome of testing, if your ECU is faulty and you choose to go ahead with the rebuild then we will take payment over the phone using a debit/credit card.

We will then rebuild your Fiat 500 Engine Control Unit and return it to you with an unlimited mileage warranty.

If you require further information regarding this Fiat 500 ECU then please contact us.

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Comments on "Fiat 500 Misfire ECU Repair"
David OHalloran says: 01/01/2020 10:11:07
do you service internationally? I am in Australia and have a misfire with my Fiat 500 Twinair. Two mechanics have failed to fix the problem. Can you assist me? Thanks David
ECU Admin says: 02/01/2020 14:19:16
Hi David, we certainly do offer international service. For prices and shipping information please select your part number above.
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