culeanu said:

Hi,....

Click to expand...

+ attached files

culeanu said:

+ attached files

Click to expand...

Thanks for the info.

What symptoms do you have and did you get it sorted?

NebulaStilo said:

Thanks for the info.

What symptoms do you have and did you get it sorted?

Click to expand...

Long story (+2years) short, my punto has a kind of fine hesitation and power loss all the way of rev.
My readings: no error codes, but total Fuel Trim at idle = around - (minus) 110%, which confirm the symptoms.
My actions: all the list attached for rich conditions already done (parts changed or tested), except a specialized test for the TDC (top dead center of timing). Which I intend to do next week.
Others: cleaned or replaced all the earth points, tested another virginised ECU. And....nothing.
So, I'm interested for any causes for extremely rich conditions, without error codes.
If you're so kind to keep us informed about the resolution, I will be grateful.
Also, I'll publish my findings, if lucky.

I'll publish in few days also my reals readings for all the sensors implicated in injection process.

culeanu said:

Long story (+2years) short, my punto has a kind of fine hesitation and power loss all the way of rev.
My readings: no error codes, but total Fuel Trim at idle = around - (minus) 110%, which confirm the symptoms.
My actions: all the list attached for rich conditions already done (parts changed or tested), except a specialized test for the TDC (top dead center of timing). Which I intend to do next week.
Others: cleaned or replaced all the earth points, tested another virginised ECU. And....nothing.
So, I'm interested for any causes for extremely rich conditions, without error codes.
If you're so kind to keep us informed about the resolution, I will be grateful.
Also, I'll publish my findings, if lucky.

I'll publish in few days also my reals readings for all the sensors implicated in injection process.

Click to expand...

I will post my resolves ??

I did change to original air filter and new filter inside. Had a stupid k&n
Symptoms got better. Pulls better but still not 100%

Can you rev your car all the way to red line?
Mine stops at around 5000 and just hangs there.

I've got hesitation through rpm too. At times there's no hesitation and she moves like a dream.

I tried Ralf S analog test at 1800rpm while driving and see what happened. She jerks at 1800rpm and if you keep her there she keeps on jerking. Always a jerk around 1800rpm. He said thats where the lambda heater turns off approx and with a jerk around that rpm indicates o2 sensor is lazy to switching between voltages

I don't have a code for upstream sensor ie the sensor that has the most to do with performance. However a lazy or bias sensor won't always show up as a fault and trick ecu that everything is fine.

I also hit -100% at idle and when pasking the car inside(start and idle her into her parking)I always pick up a strong fuel smell hence -100% fuel trim.

I checked grounds and vacuum leaks etc and all is ok.

NebulaStilo said:

...
I also hit -100% at idle and when pasking the car inside(start and idle her into her parking)I always pick up a strong fuel smell hence -100% fuel trim.

I checked grounds and vacuum leaks etc and all is ok.

Click to expand...

Lot of answers in my head...i'll try to give the most important, according my level of knowledge ?

Me, I was a part changer, but I do not recommend to others.

What I recommend: testing every single part before buying a new one. I have a box full with sensors for ignition, changed but not faulted. I'm afraid to make a sum in € ?

Back to your car, I'll concentrate to the facts that I retained and the order I would take action. Still, the accuracy of understanding for each of us is a unknown variable...

1. TPS shows about 5% at idle. Not sure if normal, I was pretty sure it should be 0%.
How can affect the fuel trim? TPS is indirect part of the entry data for the predefined fueling map. The other is RPM.
More about: http://www.formula1-dictionary.net/map_fuel.html
My suggestion :
a) a good cleaning to throttle body with carburator cleaner. Be generous. Then need to re-learn the TB to ECU.
b) testing it with the multimeter. 30 min on youtube and you'll be able.

2. Hope that 'white staff' is not a sign of contamination of the oil with the coolant or vice-verse. It's mandatory to check, since that means a head gasket to change, with all the menu...

3. Identify and Check the ECU earth, both ends of the cable; for my punto it was very tricky.
Short solution: make a direct serious cable to the battery negative from one bolt of your ECU.

4. We have a confirmation: the smell in indoor parking confirmed a rich condition. Chances are the O2S1 to be good. Do not change it without testing. You need again a multimeter and about 30 min dedicated on youtube.

5. We can make a speculation: Because a reach condition enough time could contaminate the O2 sensor AND clogging the CAT, maybe this is the reason the last owner made a decat + tried to give more air to the engine with a sport filter.
(My cat was melted in the middle of the ceramic, been there also...)

6. Since we talk about sensors, it will be useful to list any single electric malfunction in the car. Then check if any fuse for that function is placed in the fuse box from engine bay, which is usually dedicated to injection. Tips: AC, interior fan, anything...

Others: We have different engines, so not so relevant, but I can rev to max (about 7000) with no load. Another speculation: maybe this is related to the 5% of TPS loosed at idle.

Sorry for this long post with condensate information , but not sure i'll have time next days to publish one by one.

culeanu said:

Lot of answers in my head...i'll try to give the most important, according my level of knowledge ?

Me, I was a part changer, but I do not recommend to others.

What I recommend: testing every single part before buying a new one. I have a box full with sensors for ignition, changed but not faulted. I'm afraid to make a sum in € ?

Back to your car, I'll concentrate to the facts that I retained and the order I would take action. Still, the accuracy of understanding for each of us is a unknown variable...

1. TPS shows about 5% at idle. Not sure if normal, I was pretty sure it should be 0%.
How can affect the fuel trim? TPS is indirect part of the entry data for the predefined fueling map. The other is RPM.
More about: http://www.formula1-dictionary.net/map_fuel.html
My suggestion :
a) a good cleaning to throttle body with carburator cleaner. Be generous. Then need to re-learn the TB to ECU.
b) testing it with the multimeter. 30 min on youtube and you'll be able.

2. Hope that 'white staff' is not a sign of contamination of the oil with the coolant or vice-verse. It's mandatory to check, since that means a head gasket to change, with all the menu...

3. Identify and Check the ECU earth, both ends of the cable; for my punto it was very tricky.
Short solution: make a direct serious cable to the battery negative from one bolt of your ECU.

4. We have a confirmation: the smell in indoor parking confirmed a rich condition. Chances are the O2S1 to be good. Do not change it without testing. You need again a multimeter and about 30 min dedicated on youtube.

5. We can make a speculation: Because a reach condition enough time could contaminate the O2 sensor AND clogging the CAT, maybe this is the reason the last owner made a decat + tried to give more air to the engine with a sport filter.
(My cat was melted in the middle of the ceramic, been there also...)

6. Since we talk about sensors, it will be useful to list any single electric malfunction in the car. Then check if any fuse for that function is placed in the fuse box from engine bay, which is usually dedicated to injection. Tips: AC, interior fan, anything...

Others: We have different engines, so not so relevant, but I can rev to max (about 7000) with no load. Another speculation: maybe this is related to the 5% of TPS loosed at idle.

Sorry for this long post with condensate information , but not sure i'll have time next days to publish one by one.

Click to expand...

Thanks for the reply. I'll need to get hold of a cheap and decent multimeter.

Ive read that tps should be around 5% at idle however i do know that there is an update for the tps on the 1.6 stilo.

Can I update on my own and what do I need to update ?

Also I fitted the sports filter after losing mine when it came loose(somehow) from shaking. I stay in gravel road area(farm).it fell as I pulled out my driveway and cracked. Got hold of good second hand original filter eventually.

Decat was probably because it was blocked. He fit a aftermarket exhaust which actually sounds pretty decent with a Cowley box before the tip.
She used to go and move pretty quik.

Ground connected to ecu mount is good.i moved ECU against battery box because many mentioned on this forum that heat and shaking from being mounted on engine can make pins drop.

Where can i get the tps update ?

NebulaStilo said:

Where can i get the tps update ?

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Unfortunately, I can't help with specific details for stilo. Maybe there is a dedicated topic.

If 5% TPS is normal, next points should be analysed and excluded until the real fault is revealed.

Otherwise, you'll be forced to retake one by one all the suspected areas and testing them properly. I'm here now ?

Of course, the motivation, the budget and the intended ownership of the car really matters.

culeanu said:

Unfortunately, I can't help with specific details for stilo. Maybe there is a dedicated topic.

If 5% TPS is normal, next points should be analysed and excluded until the real fault is revealed.

Otherwise, you'll be forced to retake one by one all the suspected areas and testing them properly. I'm here now ?

Of course, the motivation, the budget and the intended ownership of the car really matters.

Click to expand...

I'm going through each step. Next is to get a multimeter and backprobe my o2 sensor to see what happens to her voltages. Ie a test seperate from the obd.
I'll remove air pipe to allow more oxygen and see what happens to o2 sensor and how quik she reacts. They say it should be almost instantly.

Can intake manifold(not tps,cleaned that)be blocked on a indirect injection car like the stilo? Is it worthwhile cleaning the manifold that lays above the engine on 1.6 ?

Thank you.