fiat punto

[libby lou lou]

I am having trouble with a punto sporting, i think 1.4? it's a really good engine, or at least was, as it's now missing on pots 3-4, i've changed one coil pack which made little difference, changed leads, plugs on offending pots.
I also had a ecu decoded to a plug and play, also changed the suspect injectors. I am still stuck with the problem, i had it read awhile back, and was told the ecu. What have i missed?can't afford to scrap it, as iv'e too much in it now. all ideas are welcome, thanks.

 

[jetex]

It's possibly the e.c.u as this is a (fairly) common failure. To diagnose this, you need something called a noid light or an l.e.d circuit tester, but definitely NOT a bulb type test lamp. Pull one of the plugs of the coil pack and link your circuit tester accross the terminals in the plug. Crank the engine over on the key, and the circuit tester should flash. This is the e.c.u switching the coil. Repeat the process on the other coil. If one coil plug flashes but the other one doesn't, it's an e.c.u failure. The e.c.u is located on the throttle body. You can change this without having to re-programme it. Fit the new (or second hand) e.c.u, let it idle for a while, then rev the engine quite highly a couple of times, and that's it !

 

[Mickymoody]

What is the result of the ECU decode? For an ECU to be faulty is 99.9% not going to be faulty.

You say you replaced one coil pack? for a twin spark plug pack?..

 

[libby lou lou]

jetex, where on the throttle body?as theres two on mine if i'm looking in the right place.

MM, don't know about the main ecu, ordered as second hand one, sent it to a decoder, put in on the car, and nothing has changed.
Yes, the ciol pack splits, and i just changed the suspect one,as the replacement i had was nearly new.

 

[jetex]

I'm assuming that you've got the normal 8 valve engine ?? If so, then it's the part with the throttle butterfly in it.

 

[libby lou lou]

hi, sorry no this is the sporting it's a 16v, i think the engine is 1242cc, so it has two electric units on the body. thanks.

 

[jetex]

I have a Punto sport, but it has the 8 valve engine. Can't remember which unit you need to change on the 16 valve without looking at it. Sorry.