Hi I have a 97 bravo 1.6sx. my injector light comes on during idle and acceleration, running is rough and slow, the usual fiat bravo story. a diagnostic check gave the error code indicating a faulty coil. the coil has been replaced, as well as the plugs and leads. this has made no difference. the injector light is still on. a further diagnostic check shows the same coil error still showing up on the ecu. my new coil, leads and plugs have been tested on another bravo and work fine?! do i need to have the fault code cleared or should it dissapear when the problem is fixed? if the coil is indeed working ok then does this remaining fault code indicate a faulty ecu? any advice gratefully recieved.

Does it idle smoothly now? If not then there is still a fault.

If the work was done at Fiat they would reset the code for you. If you got the error read at Fiat and went home to fix it then yeah you will need to have it reset unless your car still feels like its not running smoothly.

Joske

Joske, the light goes out the moment the ECU detects the fault isn't there, its not like the airbag.

After a number of engine starts the ECU forgets the codes anyway.

the car still runs rough and is slow, i replaced coil myself but fiat read the code for me. if there is a faulty injector would that fault definately show up on a diagnostic?

Yes it would show up but you can check them with a multimeter.

Did you check the wiring from the ECU to the coil?

according to haynes manual there are 3 wires connected to coil, 2 go to ecu and one goes to the multi-relay in the engine bay. i was thinkin bout testing all three wires using a 12v bulb to check the wires aren't broken. i'll also try replacing the multi relay. beyond that i don't know what to do. i cant afford to go back to fiat. they dont seem to know what they're doing anyway...

If the relay was at fault NOTHING would work.

any way i can check if the ecu is at fault? can i try swapping my ecu with another that i know works fine?
i believe the bravo immob ecu is separate fom the main ecu, and the main ecu can learn any immob codes the immob ecu sends it. is that true?

Check the wiring with a multimeter.

Hello,

You wont be able to just swap in another ECU from a different car, as the code in this wont match the immobiliser code.. this can only be done with a new (virgin) ECU from FIAT.

Dont go purely by diagnostic codes - they can lead astray sometimes..

Owen.

i tried testing the 3 wires connected to the coil. all 3 tested ok on continuity, which means.... i'm stuck. if i'm not to believe fault codes, then is it possible i've got a faulty injector which isn't showing up? is it possible that my ecu could be damaged, and thats why the coil fault code is still there? i'm lost for ideas

The coil fault code is there cos the ECU believes its at fault.

Take it to an independant auto electrician, they should be able to test for correct operation of the ECU, coils and injectors.

its been to 2 independent fiat specialists and a fiat dealer. they all say the same thing. they dont really know whats wrong but its probable a dodgy wire somewhere. wtf??

do you have a good decent spark from all four plugs - did you check the spark just from the plug leads themselves to earth and see how long the spark will jump ?. Its possible there is a fault in the ECU (coil drivers) which is causing it to show a problem with the coils even though they are ok. But if you have good sparks, its likely there is another problem.

Owen.

gettin a compression test done on friday. gonna start with the basics and check everything twice. i think the fault code isn't right. all 4 plugs are sparkin lovely. a multimetre test of the coil and the three wires connected to it went fine. judging from the constant misfire i think it probably is an injector fault but i cant undestand why no fault code is showing for it. the injector light can come on for many reasons and not leave any fault code according to my local fiat garage. great...