Morning folks.


Seeming as I keep having issues and a lot of the replies I got where not about my motor I thought best to make a new thread.


https://www.fiatforum.com/panda/479368-laying-over-2nd-20-30mph-panda-1-1-a.html


The story so far;


My 2009 Panda 1.1 with 20,000miles on it wasn't reving on occasion. Threw up a P0130 error code.


Chucked in a new O2 sensor, went away for a bit, came back, car wouldn't rev right.


Today the issues upped themselves.


The idle decided to peg itself to 2000-3000rpm when WARM.


Also got a new error code; P0150 along with P0130 and P0171


So what the hell do I do now?


I can't drive the car. It also managed a new horrible plastic smell which I'm assume is the sky high idle not helping.


What do I do? Do I bypass all the o2 sensor wiring and do it direct to the ECU? As I got no idea where which wires go for that. Or do I bite the bullet and take it to the dealer ... who'll prob not fix the bloody thing right either.

So many "random" errors looks like an ECU fault or it's connecting plug or it's wiring bundle.

DaveMcT said:

So many "random" errors looks like an ECU fault or it's connecting plug or it's wiring bundle.

Click to expand...

Anything more specific or do I just start grabbing wires?

Edit

Okay, less angry now. So do I want to start the car and just grab every plug and wiggle it, or is there a specific few places where I get fretting?


Are the cables or the connectors normally the problem?

I still think it's sucking in air in a place that it's not supposed to do. Hence the lean mixture, high idle and lambdasensor that is unable to cope.

gr J

BigAdam said:

Anything more specific or do I just start grabbing wires?

Edit

Okay, less angry now. So do I want to start the car and just grab every plug and wiggle it, or is there a specific few places where I get fretting?


Are the cables or the connectors normally the problem?

Click to expand...

Check for air leaks with some flammable spray. If its leaking engine revs will change.

The 1.1 ECU wiring and connector issues are well covered in the forum. It's the only one with the ECU bolted to the engine so this may be why the 1.2 and 1.4 are generally ok.

DaveMcT said:

Check for air leaks with some flammable spray. If its leaking engine revs will change.

The 1.1 ECU wiring and connector issues are well covered in the forum. It's the only one with the ECU bolted to the engine so this may be why the 1.2 and 1.4 are generally ok.

Click to expand...

Aye the wiring covered, but no one says what to check.


"There's a dry Y joint" ... where? Thats about the most I've gotten.


Anywho.

I went and sprayed, fiddled, grabbed, wiggled, and flicked every connector I could find on top of the engine.


You can hear the car hunt up and down the rev range.


https://www.youtube.com/watch?v=IhyH1ko_yZ0&feature=youtu.be

I got no idea what else to check now.


Still getting P0150, P0130 and P0171.


Put in a new O2 sensor already, changed the top pre-cat one. Think I should give the post cat one a try too?

Swap the O2 sensors and see if the codes change.

Spraying flammable stuff on the engine has to be done methodically. Find a suspect, spray, listen, move on.

P0171 code means the fuel system is running weak or a vacuum leak exists. A spark missfire will cause the O2 sensor to see a weak mixture. But first you have to find the cause of the revving under no load. That is almost certainly an air leak.

DaveMcT said:

Swap the O2 sensors and see if the codes change.

Spraying flammable stuff on the engine has to be done methodically. Find a suspect, spray, listen, move on.

P0171 code means the fuel system is running weak or a vacuum leak exists. A spark missfire will cause the O2 sensor to see a weak mixture. But first you have to find the cause of the revving under no load. That is almost certainly an air leak.

Click to expand...

Physically swap em or switch the cables over.


Brake cleaner work for spraying or do I want to use propane. Still don't think its an airleak, as its too methodical. Listen to it, thats the idle control valve trying to keep stuff running.


... I put new spark plugs in, but I never changed the HT leads. Worth a try?

BigAdam said:

Put in a new O2 sensor already, changed the top pre-cat one. Think I should give the post cat one a try too?

Click to expand...

Sounds like shooting the messenger. O2sensor says mixture is lean. Let's change the O2sensor...
Yes your throttle is frantically trying to get the mixture on lambda. But that's probably a symptom, not the cause.

gr J

A3jeroen said:

Sounds like shooting the messenger. O2sensor says mixture is lean. Let's change the O2sensor...
Yes your throttle is frantically trying to get the mixture on lambda. But that's probably a symptom, not the cause.

gr J

Click to expand...

To quote the Simpsons.


"We tried nothing and we all outta' ideas"

So I decided to swap in the old o2 sensor and swap it with the pre / post cat o2 sensors.


So we got a known working one in the pre-cat position.


Still get the Too Lean error.


BUT!


I noticed something. I noticed the o2 was F'ing covered in carbon / soot. This o2 has been in there maybe a month. So I checked the new 3 day old spark plugs and hey look the same problem.




EVERY spark plug was black and sooty. These things are a couple days old with maybe, MAYBE 20-30miles on them.


So something is making my car think its way too rich.


Can I bypass the loom and pick up straight off the ECU for the o2?

Anyone got an ECU pinout?

AND! Does the heater circuit on the o2 heat up on run position or do I have to crank it?

EVERY spark plug was black and sooty. These things are a couple days old with maybe, MAYBE 20-30miles on them.

Spark missfires cause rich running. Did you change the coils?

DaveMcT said:

EVERY spark plug was black and sooty. These things are a couple days old with maybe, MAYBE 20-30miles on them.

Spark missfires cause rich running. Did you change the coils?

Click to expand...

Not changed coil yet, got some on order. They do spark like a mofo as I tried pulling plugs to see.


But everything is black and sooty. From the spark plugs to the o2 sensors.


If I unplug the o2 sensors, will it go to a default map and hope for the best.

Hi All

its a bit random but have you checked the water level as im concerned the engine has got too hot and melted the inlet manifold at the back and hence letting excess air in, upsetting everything. Could this have been the source of your hot plastic smell.

Tim

timmycm850 said:

Hi All

its a bit random but have you checked the water level as im concerned the engine has got too hot and melted the inlet manifold at the back and hence letting excess air in, upsetting everything. Could this have been the source of your hot plastic smell.

Tim

Click to expand...

No puddle, still full of water, gonna have to take off that small bracket that holds a few bits to have a proper look tomorrow.

I am officially out of ideas.


Tried so far;

• New O2
• Swapped O2 sensors.
• Put in old O2 sensor.
• Checked O2 get power and continuity to ECU
• New Spark plugs.
• Checked for missfire / no spark by yanking each HT lead and listening to change. Every time I pulled a plug it would run rougher.
• Checked for air leaks, found none.

And STILL it says its lean and hunts up and down.


I got all these great codes now.




I think I need an actual mechanic now. I got no idea anymore.

Update, as I hate those threads that go to nothing.


I gave up and gave it to the mechanic. The MAF sensor wasn't reading correctly, so he changed it and it helped, so he also changed the throttle body and that sorted it.


So , dear reader, MAF or throttle body or both.