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Tibby's advice suggests checking fuses to see iif they have blown and if they have, then check connectors for water ingress on the sensors throwing the codes. I would check there before going any further with the diagnosis.
Looking at the manual, I see no fuse that specifically relates to O2 sensors or emissions system.
Going to see if the schematics in the service manual show anything, but more likely a bad ground if the battery and connections are good. IMHO.

Don't forget, the above code information, though very good, is somewhat generic.
 

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If anyone can make sense of this...
K017 and K015 are the two Oxygen sensors.
The common fuse is the 20A "Powertrain" fuse, which I suspect would cause a Christmas Tree of Death, or no drive-ability, if blown.

113265

113266

113267

113268
 

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Troubleshooting guide for P0136
113270


113271


113272

113273

I don't see similar tables for P0138 but chances are that this might give you something to think about...
 

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I have the stradale exhaust with control valve. I have the novetic downpipe on instead of the cat
You've got the oem ecu installed and have NO cat? Please see mr :poop:




Deceptive Oxygen Sensor Codes
While it’s common for the HO2S to wear out over time, there are a number of other issues that trigger a P0138 diagnostic code and have nothing to do with the oxygen sensor. These include:
  • An inefficient catalytic converter. THIS ONE :poop::poop::poop::poop:
  • Engine vacuum leaks that create a lean exhaust condition.
  • Mass airflow sensor failure that creates a rich exhaust condition.
  • Manifold air pressure sensor failure that creates a rich exhaust condition.
  • Exhaust leaks that contribute to a lean exhaust condition.
  • Ignition misfires that lead to a rich condition.
  • Leaky fuel injectors that create a rich condition.
  • A defective fuel pressure regulator.
  • A blown fuse.
  • Burned or damaged wiring and/or connectors.
As you can see, the list goes on and on. This is why we always recommend a complete diagnosis. We hate to see situations where a vehicle owner tries to save a few bucks by having the code pulled for “free” somewhere and rushes out to buy an oxygen sensor just because it is listed in the trouble code description. The part is replaced, but the problem persists.
 

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I have the stradale exhaust with control valve. I have the novetic downpipe on instead of the cat
You need a CAT delete tune if you do not have it already. If you have the CAT delete tune then it does not make sense why you are getting O2 codes.
 

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You need a CAT delete tune if you do not have it already. If you have the CAT delete tune then it does not make sense why you are getting O2 codes.
He said that he believes he has this (maybe I'm wrong with that understanding, or they didn't include that in his tune). The first post suggested that the problem developed toward the end of a track day, not when he installed the downpipe.

Also, his OEM ECU seems to have completed the test cycle in a drive of only about 30 miles (which seems really fast to me - my experience was more like 60-100 miles of varied driving. He said that he did 30 miles or so without issues (stock ECU), stopped the car, re-started it and within a few feet the CEL came up and the car went into limp mode.

Also, initially many codes came on (including with e-brake on), which is indicative of a voltage issue. Now it is down to these O2 sensor codes.

Now I'm Broke, is there any sign of an exhaust leak at the turbo or midpipe connections? Even a small one?
Otherwise, I'd go back to thinking it's a loose connection somewhere - fuse box, ground, or something that these two sensors have in common. But I'm at the end of my Latin here.
 

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Discussion Starter #69
You've got the oem ecu installed and have NO cat? Please see mr :poop:




Deceptive Oxygen Sensor Codes
While it’s common for the HO2S to wear out over time, there are a number of other issues that trigger a P0138 diagnostic code and have nothing to do with the oxygen sensor. These include:
  • An inefficient catalytic converter. THIS ONE :poop::poop::poop::poop:
  • Engine vacuum leaks that create a lean exhaust condition.
  • Mass airflow sensor failure that creates a rich exhaust condition.
  • Manifold air pressure sensor failure that creates a rich exhaust condition.
  • Exhaust leaks that contribute to a lean exhaust condition.
  • Ignition misfires that lead to a rich condition.
  • Leaky fuel injectors that create a rich condition.
  • A defective fuel pressure regulator.
  • A blown fuse.
  • Burned or damaged wiring and/or connectors.
As you can see, the list goes on and on. This is why we always recommend a complete diagnosis. We hate to see situations where a vehicle owner tries to save a few bucks by having the code pulled for “free” somewhere and rushes out to buy an oxygen sensor just because it is listed in the trouble code description. The part is replaced, but the problem persists.
My tune is a phases 2 with pops and bangs and cel delete. I ran it for months just fine. Then, when I went into the grass, everything was still fine. Untill I turned the car off and turned it back on. Then the cel comes back on. I turn it off, clear the codes, everything is peachy, till I turn the car off again. I turn it back on, It runs for about 2 minutes and then the cel comes back on.

I replace said o2 sensor. Codes still came back. I called Euro and they said they dont know what the issue is, so send the ecu back and they'll check it. But to also change the other o2 sensor just incase. I waited a week, after it was confirmed to have arrived. They said they'd get to it the next day and get back with me. Didnt hear anything for several days, so I emailed them. I got a response saying they were closed between Dec.24-Jan 4. So I wait till then and called, they dont answer. I waited a few more days. I called again and Jordan answered and said he's leave a note for Toby to go ahead and send back because I was still getting the same codes even on the original ECU so not likely it was the tune. Been over a week and I've heard zero response so I called today and they didn't answer.

This is where I'm at now. I relaced the battery last night and as of now, these are the only codes showing now. But its the same exact pattern as before.
 

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But @ the moment the oem ecu is in the car? (Because you did not recieve the tuned one yet). Correct?
If so, you can not test it properly because the oem ecu will give codes due not having a cat. You can put the oem downpipe back on for the oem ecu to test properly or wait for the tuned one with the cat delete to test properly and diagnose the problem. Good luck :confused::confused::confused:
 

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Discussion Starter #71
But @ the moment the oem ecu is in the car? (Because you did not recieve the tuned one yet). Correct?
If so, you can not test it properly because the oem ecu will give codes due not having a cat. You can put the oem downpipe back on for the oem ecu to test properly or wait for the tuned one with the cat delete to test properly and diagnose the problem. Good luck :confused::confused::confused:
The tune didnt tune out the codes that its throwing. I was getting the same codes on the tuned ecu that i am on the original, so putting the tune back on isn't gonna fix the issue i don't think, unless it was actually broken inside somehow and they were able to fix it. Thats the other issue. Waiting. I sent it in over a month ago.
 

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I was suggested to change out my coil packs because of the misfire in cylinder 4 this morning. How hard is it to change those out and replace?

After work I will be going to walmart and seeing if they have that specific battery. Dealership wants me to buy the stock battery for $209 plus tax
My dealer wanted $423 installed. Nuttty!
 

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I decided to just go ahead and buy the battery from the dealer. $229 out the door, took maybe 30 minutes to change, really easy.
I wouldn’t be using your car with the oem ecu. You’re bound to get a repeat of the codes. Wait for the return of the EC one. Then fingers crossed.
 

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The tune didnt tune out the codes that its throwing. I was getting the same codes on the tuned ecu that i am on the original, so putting the tune back on isn't gonna fix the issue i don't think, unless it was actually broken inside somehow and they were able to fix it. Thats the other issue. Waiting. I sent it in over a month ago.
If I'm reading this thread correctly @Now I’m Broke you started with 6 codes being thrown and you're now throwing 2 codes? If that is the case, I'd suspect (hope?) that the remaining 2 codes could be resolved by the tuned ECU with the cel delete. The battery or other sensor replacements you've done, or even re-seating some connections, may have resolved the other 4 codes.

I'd see if you could pay EuroCompulsion a few extra bucks to rush shipment and send you tracking info on your ECU so you can get that installed ASAP. It's been a while since I've contacted EC for anything, but a month long wait isn't the type of service experience I've had with them so I hope the experience you're having is just a holiday glitch.

Good luck with this!
 

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UK is suffering under some pretty severe Covid restrictions right now. I suspect that is impacting EC.
 

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Discussion Starter #77
So I called Euro yesterday and didn't get a response, but I checked my email later and they sent me the tracking number for my ecu. Should be here Tuesday night usps said. But bad news. My car is throwing some of the old same codes again and a new one about a knock sensor. I swear this car has a mind of its own.
 

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Discussion Starter #78
So I get my tune in today. I put it on. These are the codes that have come back.

I check all the fuses, everything looks good. I move around the relays, nothing has changed. Ive checked the wires and they're secure. I've checked to see if anything is exposed and I've found nothing.

Same as before, I turn the car on, cel comes on after about 2 minutes. I turn the car off, reset the codes, I turn the car back on and the cel doesn't come back on even if I drive 300 miles. But as soon as I turn the car off and back on, 2 minutes later the cel comes back on.

I've have noticed this though. Before I turn the car off, I plug in the OBD2 scanner and it gives me the green light, BUT, if i select to read the codes, it then sees them, but still doesnt through the CEL till I turn the car off and turn back on.

P0687 ECM/PCM Power Relay Control Circuit High
P0036 H02S Heater Control Bank 1 Sensor 2
P0138 02 Sensor Circuit High Voltage Bank 1 Sensor 2

I'm definitely burning gas and my idle is sporadic, just like it has been for months now. I've read that low voltage on the 02 Sensor means not enough fuel, and high voltage means too much. Its definitely lean with is obvious, just dont know how to fix it.

The heater control gets the 02 sensor to the right temperature so it can read properly.

And the ECM/PCM looks power relay looks just fine as far as I can tell because I switched everything out with another one, except the white relay because there was only 1 of those. Maybe thats the relay I need to change, and if so, how do I even get one?

Idk what else to do except put everything back stock, then take it to the dealership and hope they fix it under warrenty, and then put everything back on the way it is now, but thats a huge amount of time and effort but not sure what else I can do.
 

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So I get my tune in today. I put it on. These are the codes that have come back.

I check all the fuses, everything looks good. I move around the relays, nothing has changed. Ive checked the wires and they're secure. I've checked to see if anything is exposed and I've found nothing.

Same as before, I turn the car on, cel comes on after about 2 minutes. I turn the car off, reset the codes, I turn the car back on and the cel doesn't come back on even if I drive 300 miles. But as soon as I turn the car off and back on, 2 minutes later the cel comes back on.

I've have noticed this though. Before I turn the car off, I plug in the OBD2 scanner and it gives me the green light, BUT, if i select to read the codes, it then sees them, but still doesnt through the CEL till I turn the car off and turn back on.

P0687 ECM/PCM Power Relay Control Circuit High
P0036 H02S Heater Control Bank 1 Sensor 2
P0138 02 Sensor Circuit High Voltage Bank 1 Sensor 2

I'm definitely burning gas and my idle is sporadic, just like it has been for months now. I've read that low voltage on the 02 Sensor means not enough fuel, and high voltage means too much. Its definitely lean with is obvious, just dont know how to fix it.

The heater control gets the 02 sensor to the right temperature so it can read properly.

And the ECM/PCM looks power relay looks just fine as far as I can tell because I switched everything out with another one, except the white relay because there was only 1 of those. Maybe thats the relay I need to change, and if so, how do I even get one?

Idk what else to do except put everything back stock, then take it to the dealership and hope they fix it under warrenty, and then put everything back on the way it is now, but thats a huge amount of time and effort but not sure what else I can do.
Yep, that’s what I’d be doing but hoping someone can help out here in the mean time.
 
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