Hi all,

My punto is over fueling like mad, to the extent it would not start. Apparently the reason it is overfueling is that the injectors are reading to be remaining open for a period of 3 to 5mm seconds and the norm should be about 1mm. The ECU seems to be reading all the sensors OK and the coolant temp sensor appears to be OK. Any ideas on what is causing the inectors to remain open for so long? Any ideas / advice a appreciated.

dunno, not fitted one of them ebay resistors have you? try a bottle of injection cleaner in the tank only £5 so worth a try.

congrats on 6 k post dave

4 m/s at idle is the norm nothing wrong there.

does any body know what the injection light on the dashboard of a punto elx 90 means if it stays on? What do I need to do?
Tim

Thanks for the reply, hmmm 4 m/s is ok at idle.

I was told that it should be about 1 m/s, but 3 m/s to 5m/s is too high, hence the injectors are staying open too long and the car is running fuel rich.
The car failed its emissions test on this item alone.

Someone suggested the throttle position sensor, it has not come up as a fault on the ECU reading, but could this be causing the problem.

I have also been told that the vacuum in the clyinder area is too low (about 500 and it should read about 360) and the ecu feels that more fuel is required. (does this make sense)?

3.5-4.0 m/s (Sequential/singlepoint injection)
2.5-3.0 m/s (Simultaneous/multi)

Also take into account temperature of engine/choke/engine wear etc etc.Remember injectors might be staying open for longer to compensate for a fault but might not directly be the fault or only one of them might be faulty....confusing myself now

Punto's often fail MOT emission tests(dont ask me why i'm not a MOT tester)but i'm sure there are posts on this site about this & dealers have a bulletin aswell,changing the lambda doesn't always help!

Have you had any stored codes read yet? What were they?

I think I get it,

Mine is a 1995 Punto Selecta N reg, A single point injection.

Appreciated that the injectors could be remaining open to compensate for something else. The diagnostics came back with three faults.

Lambda Sensor
Low Battery Voltage
Injector Circuit -

Any ideas.

Also for further information the pressure in the clynider was reading about 500 ish and I believe the pressure should be around the 360 mark.

Any tips.

Apparently........ the MOT tester shouldnt use the ignition pick up on the emission tester but use the vehicles tacho to hold steady revs,this depends on what it failed on,sorry my attention span is short so lost interest after a bit but hopefully someone else can confirm this.
Judging my your fault codes i'd investigate the lambda sensor first.

T14086 said:

Punto's often fail MOT emission tests(dont ask me why i'm not a MOT tester)but i'm sure there are posts on this site about this & dealers have a bulletin aswell,changing the lambda doesn't always help!

Click to expand...

yes there is i made one sticky so should be at the top of punto tech section