Technical Wierd Falt with 1.2 8v punto 2001 ???

[Smith Online]

Hi,
Not had my punto long and below is the problem am having: -

I am trying to get the the bottom of the problem with my punto its currently not idleing correctly, using £20 in fuel within 2 days going only 10 miles or so. It shows 35mpg all the time on speedo and engine is not running right it sometimes nearly stalls when setting off and dont have much power.

Below is what I have done so far: -

1. oil and filter change (when putting new oil in it seemed to take forever for the oil to go down on each small ammount i put in i had to wait for the funnel I was using to empty)
2. spark plugs replaced.
3. ht/ignition leads replaced.
4. had exhaust checked it has a new cat. back box sounds noisey but no holes.
5. thermostat
6. air filter

The car engine light is not on. Therefore no clue as to the fault. I first thought the head gasket but no gunk around oil cap and the heater works fine now thermostat was replaced.

Anyone have any ideas?? I was thinking of draining oil taking rocker cover off cleaning anything found e.g gunk if headgasket had gone before i got it.
and same with sump then engine flushing and putting new oil and filter on again.

Thanks in advance for any help

Regards,
Smith Online

 

[Ziggy122]

That yellow symbol (or red insome cases) is the Engine Management Light aka the EML

that means the cars ECU has picked up a fault somewhere and by putting the light its alerted you to a fault

Now
A Rough Idle - is lumpy?
Ie its not firing on all cyclinders properly

And drinking lots of fuel
10miles on £20 is bad

Best way to find out what is going on is to get the fault codes read
This will give you a code to locate the fault

I'm going to go on the line lots of fuel been used and a rough idle is because the engine is been choked with fuel
Ie the engine is over fueling

That usually is due to the Lamba Sensor been faulty - but as said the only real way to know is with the fault code

If you have a laptop - you can get a £10 lead and download the Fiat Ecu Scan off the Lets Talk Fiat Section --> Free Diagnostic Software
OR google FiatEcuScan

Use the free version and find out whats going wrong

Ziggy

 

[Smith Online]

That yellow symbol (or red insome cases) is the Engine Management Light aka the EML

that means the cars ECU has picked up a fault somewhere and by putting the light its alerted you to a fault

Now
A Rough Idle - is lumpy?
Ie its not firing on all cyclinders properly

And drinking lots of fuel
10miles on £20 is bad

Best way to find out what is going on is to get the fault codes read
This will give you a code to locate the fault

I'm going to go on the line lots of fuel been used and a rough idle is because the engine is been choked with fuel
Ie the engine is over fueling

That usually is due to the Lamba Sensor been faulty - but as said the only real way to know is with the fault code

If you have a laptop - you can get a £10 lead and download the Fiat Ecu Scan off the Lets Talk Fiat Section --> Free Diagnostic Software
OR google FiatEcuScan

Use the free version and find out whats going wrong

Ziggy

Hi
I have a reader for the car and there is no faults and the engine light is not on??

Regards,
Smith Online

 

[Trooper1]

I have pretty much the same with mine Idle is rough "Lumpy" and fuel consumtion is High No engine Light is on also the same as you Sluggish resonse..Dont wanna hijack your thread but if someone knows what it is maybe they can help both of us at the same time

 

[Ziggy122]

does the cars fan run constantly when you drive?

I'd be inclined to see what happens if you unplug the Lamba sensor to see what the car does

Ziggy

 

[Smith Online]

does the cars fan run constantly when you drive?

I'd be inclined to see what happens if you unplug the Lamba sensor to see what the car does

Ziggy

Hi,
No cars temp is fine not overheating and fan runs as normal when needed.

Regarding lamba i will try that.

EDIT: Just been out to the car and unplugged both lamba sensors its still not running right and not idleing right but it seems to have got a small ammount of power back.I ran the car for over 5 mins and went around the block init and the engine light has come on which i knew it would ??????

Regards,
Smith Online

 

[Ziggy122]

just checking the temperature guage is masking the reason why
if the fan is working on demand then its fine

the lamba sensors seem to fail and give the incorrect voltage to the ECU
The ECU runs of a very sensative voltage to adjust the fueling for the car
if im rembering correctly its a 0 to 1v reading, with 0.1 been to rich and 0.9 been too lean

if the lamba says too rich - the ecu leans out the mixture
if the lamba says too lead - the ecu richens the mixture

when the lamba fails it kinda sticks at the Rich setting, and the ecu as a result is just pouring fuel in as fast as it can

smith online since you have a suitable cable, get fiat ecu scan and use the record date feature to see what the lamba sensor is reading out
that'll help you out alot

As the ecu sometimes doesn't see it been wrong unless its no signal


ZIggy

 

[Smith Online]

just checking the temperature guage is masking the reason why
if the fan is working on demand then its fine

the lamba sensors seem to fail and give the incorrect voltage to the ECU
The ECU runs of a very sensative voltage to adjust the fueling for the car
if im rembering correctly its a 0 to 1v reading, with 0.1 been to rich and 0.9 been too lean

if the lamba says too rich - the ecu leans out the mixture
if the lamba says too lead - the ecu richens the mixture

when the lamba fails it kinda sticks at the Rich setting, and the ecu as a result is just pouring fuel in as fast as it can

smith online since you have a suitable cable, get fiat ecu scan and use the record date feature to see what the lamba sensor is reading out
that'll help you out alot

As the ecu sometimes doesn't see it been wrong unless its no signal


ZIggy

Hi,
Ok I will read asap my device shows stats on screen I will edit this post with results in 10-15mins.

Regards,
Smith Online

 

[Smith Online]

Hi,
Before I viewed live data i check current fault codes which were both lamba sensors which i erased but they was also the new code which is a manufactuer pacific code.

U1601 - C-Can line error (High speed CAN network).
EDIT: (found what this code is its because i changed the speedo to one with rev counter and the instrument cluster / speedo is flashing becuase millage is different need to fix this later)

I also did a o2 bank test on the lamba sensors with the following results:

O2 bank 1 (lamba sensor 1)
Mod: $10
Meas: 0.46

O2 bank 2 (lamba sensor 2)
Mod: $10
Meas: 0.46

Here for full live readings data of the car running at idle: -

DTC_CNT 0
FUELSYS1 CL (changes to OL-DRIVE when you press the gass peddel)
FUEL SYS 2 N/A
LOAD_PCT (%) (changes from 2.7 to 3.9 all the time)
ETC ('F) 167
SHRTFT1 (%) (changes from 0.3 TO 16.4 all the time)
LONGFT1 (%) -25.8
MAP (INHG) 10.9
RPM (/MIN) 748
VSS (MPH) 0
SPARK ADV (') 10
IAT ('F) 91
TP (%) 0.00
02B1S1 (V) (changes all the time from 0.040 to 0.735)
SHRTFTB1S1 (%) 0.00
O2B132 (V) (changes all the time from 0.040 to 0.735)
SHRTFTB1S2 (%) 0.00
OBD EOBD
MIL_DIST (MILE) 0

Regards,
Smith Online

 

[Smith Online]

Bump

 

[DaveMcT]

See what Ziggy says but I'm thinking the front Lambda but saying that, both are showing identical figures and both are low which is odd. Has anyone cleaned the lambda heads?

BTW. Why was the catalyst changed might give a clue as to what's going on.

 

[Smith Online]

See what Ziggy says but I'm thinking the front Lambda but saying that, both are showing identical figures and both are low which is odd. Has anyone cleaned the lambda heads?

BTW. Why was the catalyst changed might give a clue as to what's going on.

Hi,
Not sure why cat was changed it was done by previous owner.No I havent Cleaned heads on lambas but was thinking of doing that.

Regards,
Smith Online

 

[DaveMcT]

If they are cleaned they wont work properly.

 

[Ziggy122]

you going on assumption they've swapped cat over and wiped the sensor clean and killed them?

there is the graph feature on fiat ecu scan, set it for lambas only and take a print screen of what it looks like

If im right in saying, it should be wavey

Ziggy

 

[Smith Online]

you going on assumption they've swapped cat over and wiped the sensor clean and killed them?

there is the graph feature on fiat ecu scan, set it for lambas only and take a print screen of what it looks like

If im right in saying, it should be wavey

Ziggy

Hi,
My device connects direct to car with no laptop. Therefore i cant use fiat ecu scan at the min.

regards,
Smith Online

 

[DaveMcT]

you going on assumption they've swapped cat over and wiped the sensor clean and killed them?

there is the graph feature on fiat ecu scan, set it for lambas only and take a print screen of what it looks like

If im right in saying, it should be wavey

Ziggy

Not assuming its the lambdas having been wiped clean - it just might be what's happened. Supported by those voltage readings looking low and both identical is even more odd.