2004 yaris rough idle

[Terry RD400]

2 hours ago, corradovr6 said:

How is it running at present?  Hopefully it has been solved but if not, any chance of swopping the injectors over to replicate the issue? 

With P0100, if you delete, run the car and rescan does it come back?  Might be worth spraying the connector with contact cleaner first as well as giving the MAF a good blast.  Leave to dry properly and then reinstall.

Hi Hassan, thanks for keeping an eye on me :). I could not buy the MAF cleaner anywhere near me, none at SCs (GSF), Euro Car Parts, Jayar Car Parts. I have a can arriving tomorrow from that Large River Company. Once sprayed, contacts cleaned (look good though), I will delete the error code and try again. I will keep you posted. I have a question for you? Have you ever drilled a barrel out of a lock? Reason I ask is if this fails, I am going to buy a second hand ECU barrel and keys

[stantheman1]

The P0100 code may be just down to disturbing the sensor connection, make sure it's 'fully home', so that you hear that resounding 'click'.

As above, is the car running okay now?

[stantheman1]

6 hours ago, Terry RD400 said:

Got an error message of P0100 - MAF. Just ordered a can of cleaner. I'm not convinced this is the problem though, but I would love to be wrong. I would expect this problem to effect all cylinders not just one.

....Not only that but your fuel graphs would be way out. You've probably just disturbed it by getting to the injectors, try the connector again.

[corradovr6]

12 hours ago, Terry RD400 said:

Hi Hassan, thanks for keeping an eye on me :). I could not buy the MAF cleaner anywhere near me, none at SCs (GSF), Euro Car Parts, Jayar Car Parts. I have a can arriving tomorrow from that Large River Company. Once sprayed, contacts cleaned (look good though), I will delete the error code and try again. I will keep you posted. I have a question for you? Have you ever drilled a barrel out of a lock? Reason I ask is if this fails, I am going to buy a second hand ECU barrel and keys

Hi Terry, i think you can swop the fob internals over and then re-pair the  key to the ecu. Means you keep the same mechanical part of the key.

All the best - i know you're going to solve this!

[Terry RD400]

16 hours ago, stantheman1 said:

The P0100 code may be just down to disturbing the sensor connection, make sure it's 'fully home', so that you hear that resounding 'click'.

As above, is the car running okay now?

Hi Stan, patiently waiting for the MAF cleaner to arrive very shortly. I will keep you posted on the outcome. I have worked out how to view a live data stream, but have no idea how to understand the data. The file is 390mb (5mins) so this may or may not upload.

[Terry RD400]

3 hours ago, corradovr6 said:

Hi Terry, i think you can swop the fob internals over and then re-pair the  key to the ecu. Means you keep the same mechanical part of the key.

All the best - i know you're going to solve this!

That's really good news if I can swap the fobs and repair. Thanks Hasan, the boost of confidence is really appreciated

[stantheman1]

2 hours ago, Terry RD400 said:

Hi Stan, patiently waiting for the MAF cleaner to arrive very shortly. I will keep you posted on the outcome. I have worked out how to view a live data stream, but have no idea how to understand the data. The file is 390mb (5mins) so this may or may not upload.

The idle speed seems to be rather high approx 1400rpm especially when the engine coolant temperature is at normal operating temp and therefore the maf readings are meaningless, at idle it should read appro. 1.3g/s. The fuel trims looked good at times.

The best info you could provide is the freeze frame data when a fault occurs, that way we'll be able to see the relevant info. Don't clear the codes until you have saved/recorded the data.

There's no harm in cleaning the maf sensor (provided you do it correctly as not cause any damage to it) but I very much doubt that'll fix your issue as your fuel trims look good.

 

[Terry RD400]

21 minutes ago, stantheman1 said:

The idle speed seems to be rather high approx 1400rpm especially when the engine coolant temperature is at normal operating temp and therefore the maf readings are meaningless, at idle it should read appro. 1.3g/s. The fuel trims looked good at times.

The best info you could provide is the freeze frame data when a fault occurs, that way we'll be able to see the relevant info. Don't clear the codes until you have saved/recorded the data.

There's no harm in cleaning the maf sensor (provided you do it correctly as not cause any damage to it) but I very much doubt that'll fix your issue as your fuel trims look good.

 

Thanks for taking the time to look at the data. My can of MAF cleaner has just turned up, so going to clean the sensor and put it back together. How do I access the freeze frame data as the fault occurs? If you can possibly tell me how to get this data in the next 30 minutes before I start the car I would really appreciate it. Thank you.

[stantheman1]

12 minutes ago, Terry RD400 said:

Thanks for taking the time to look at the data. My can of MAF cleaner has just turned up, so going to clean the sensor and put it back together. How do I access the freeze frame data as the fault occurs? If you can possibly tell me how to get this data in the next 30 minutes before I start the car I would really appreciate it. Thank you.

Hi Terry

Just hook up the scan tool to your car and go through the various menu options until you see freeze frame, there will only be data if a fault is present. Good luck, let us know how you get on.

[Terry RD400]

12 minutes ago, stantheman1 said:

Hi Terry

Just hook up the scan tool to your car and go through the various menu options until you see freeze frame, there will only be data if a fault is present. Good luck, let us know how you get on.

Hi Steven, thanks for getting back to me. The car is back together and I have just come in to check if you had answered me, thank you again. I remember where the freeze frame was and when I pressed it before it said there was no freeze frame data, are you saying that this will only collect data upon a fault occuring?

[Terry RD400]

11 minutes ago, Terry RD400 said:

Hi Steven, thanks for getting back to me. The car is back together and I have just come in to check if you had answered me, thank you again. I remember where the freeze frame was and when I pressed it before it said there was no freeze frame data, are you saying that this will only collect data upon a fault occuring?

Can I drive along with the OBD connected?

[stantheman1]

Yes and yes.

[Terry RD400]

6 hours ago, stantheman1 said:

Yes and yes.

Sorry this one is late. MAF all good, error code cleared but not convinced this was the misfire problem.

I took the car on a long drive, here there everywhere. I decided to visit my brother as ended up his way I timed the drive and it drove without fault for just shy of 65 minutes, basically switched it off at my brothers. I have not told you guys this, but when the fault was only a few days old, it had a habit of driving fine and then when I switched it off, but switched it on again 30 minutes later the misfire would be there instantly and stay. I had a coffee at my brothers and left, 100 meters up the road the engine management light comes on. I pull over and that same misfire code was there on cylinder 3. It misfired for about 1/2 a mile and cleared itself. I drove it back home (30 minute away) without fault. My brother is saying ECU again to me, what do you think?

[stantheman1]

They very rarely fail unless they've been subject to heat and moisture. If the error code is still there then pull the freeze frame data to see what when wrong.

[Terry RD400]

6 hours ago, stantheman1 said:

They very rarely fail unless they've been subject to heat and moisture. If the error code is still there then pull the freeze frame data to see what when wrong.

The footwell did get very wet/saturated last year, when I went through an extremely large puddle/small lake at night. There was so much water I had to empty the air filter box and buy a new filter, but that was at least 7 months ago.

So still not convinced. Every time I press the freeze frame button it says something along the lines of no data for this vehicle (I think). When I go back out to the car I will start it and video what I do so you can see what I am doing.

What is Bank1-Sensor 1 - When I selected this it came up with the following (this was me just digging around the OBD looking for a fail).
Low Sensor Voltage - PASS
High Sensor Voltage - PASS
Minimum Sensor Voltage - FAIL
Maximum Senor Voltage - FAIL

What are DTC's? Under faults its said No DTC's

[stantheman1]

1 hour ago, Terry RD400 said:

The footwell did get very wet/saturated last year, when I went through an extremely large puddle/small lake at night. There was so much water I had to empty the air filter box and buy a new filter, but that was at least 7 months ago.

So still not convinced. Every time I press the freeze frame button it says something along the lines of no data for this vehicle (I think). When I go back out to the car I will start it and video what I do so you can see what I am doing.

What is Bank1-Sensor 1 - When I selected this it came up with the following (this was me just digging around the OBD looking for a fail).
Low Sensor Voltage - PASS
High Sensor Voltage - PASS
Minimum Sensor Voltage - FAIL
Maximum Senor Voltage - FAIL

What are DTC's? Under faults its said No DTC's

DTC's are diagnostic trouble codes and as there aren't any then there won't be any data in the freeze frame to show. When the check engine light is on then the data can be viewed.

Bank 1 Sensor 1 will be the pre cat oxygen sensor (the yaris has only one bank).

 

[stantheman1]

1 hour ago, Terry RD400 said:

The footwell did get very wet/saturated last year, when I went through an extremely large puddle/small lake at night. There was so much water I had to empty the air filter box and buy a new filter, but that was at least 7 months ago.

So still not convinced. Every time I press the freeze frame button it says something along the lines of no data for this vehicle (I think). When I go back out to the car I will start it and video what I do so you can see what I am doing.

What is Bank1-Sensor 1 - When I selected this it came up with the following (this was me just digging around the OBD looking for a fail).
Low Sensor Voltage - PASS
High Sensor Voltage - PASS
Minimum Sensor Voltage - FAIL
Maximum Senor Voltage - FAIL

What are DTC's? Under faults its said No DTC's

I would visually check all the electrical connections to sensors etc to see if there's any sign of corrosion, a spray of contact cleaner will help tremendously, I would also check the connections of the ecu as well. 

[Terry RD400]

19 hours ago, stantheman1 said:

DTC's are diagnostic trouble codes and as there aren't any then there won't be any data in the freeze frame to show. When the check engine light is on then the data can be viewed.

Bank 1 Sensor 1 will be the pre cat oxygen sensor (the yaris has only one bank).

 

Thanks Steven

[Terry RD400]

On 5/9/2022 at 10:55 AM, Terry RD400 said:

Thanks Steven

Here's the latest. Run terribly yesterday, the usual cylinder 3 misfire problem. Grabbing at straws, I removed and cleaned every earth strap I could find above and below the engine.

Next I went to the ECU there was a lot of foul water splashed marks everywhere around the ECU and underside of glove box from when I went through the massive country lane puddle last year. I wanted to check the connections but soon realised it has 2 security screws on it. Do you or anyone you know what size these security screws are my T25 was to big, T20 was to small.

[flash22]

LTFT is bordering on lean, STFT is borderline rich, idle is v. high for up to temp engine in closed loop, MAF looks good for the rpm

have a look at the misfire counters and post the o2 voltages when cold if you can

does the engine rev cleanly if you snap the throttle

 

1st job is disconnect the Battery and let the ecu reset

[Terry RD400]

2 hours ago, flash22 said:

LTFT is bordering on lean, STFT is borderline rich, idle is v. high for up to temp engine in closed loop, MAF looks good for the rpm

have a look at the misfire counters and post the o2 voltages when cold if you can

does the engine rev cleanly if you snap the throttle

 

1st job is disconnect the battery and let the ecu reset

Hi Bob, whats LTFT and STFT? and would it make any difference if the air filter was off when I took the video?

When the car is cold for about 8 minutes (on average) it runs 100%, then it drops cylinder 3. Where would I find the misfire counters. I think I can find the o2 voltages tomorrow morning when its cold again and take some pictures.

Today I checked the earths and they are all good and clean.

I started the car about 40 minutes ago and as usual it runs, revs, everything clean until it dropped cylinder 3. I disconnected the coil pack on 3 and lifted it outside the engine and put an old plug inside and reconnected the wiring it sparked but it was coming out of the side of the spark plug and not reaching the electrode on the end. As I want to be honest hear, I put the new plugs straight in and did not gap them would this cause a problem? Before you ask, I did not drop them into the head I lowered them with my magnet and got a couple of turns on before I put the plug socket on. Please don't forget that coil pack 3 is firing but MISFIRING on 3.

Also when I go to Diagnose Process on my OBD I always select OTHER AREA is this correct? Because if I choose JAPAN AREA I get the message below.

[flash22]

LTFT and STFT are the long and short term fuel trims

[Terry RD400]

14 minutes ago, Terry RD400 said:

Hi Bob, whats LTFT and STFT? and would it make any difference if the air filter was off when I took the video?

When the car is cold for about 8 minutes (on average) it runs 100%, then it drops cylinder 3. Where would I find the misfire counters. I think I can find the o2 voltages tomorrow morning when its cold again and take some pictures.

Today I checked the earths and they are all good and clean.

I started the car about 40 minutes ago and as usual it runs, revs, everything clean until it dropped cylinder 3. I disconnected the coil pack on 3 and lifted it outside the engine and put an old plug inside and reconnected the wiring it sparked but it was coming out of the side of the spark plug and not reaching the electrode on the end. As I want to be honest hear, I put the new plugs straight in and did not gap them would this cause a problem? Before you ask, I did not drop them into the head I lowered them with my magnet and got a couple of turns on before I put the plug socket on. Please don't forget that coil pack 3 is firing but MISFIRING on 3.

Also when I go to Diagnose Process on my OBD I always select OTHER AREA is this correct? Because if I choose JAPAN AREA I get the message below.

Managed to get the ECU off. All the connections looked good.

[stantheman1]

1 hour ago, Terry RD400 said:

Hi Bob, whats LTFT and STFT? and would it make any difference if the air filter was off when I took the video?

When the car is cold for about 8 minutes (on average) it runs 100%, then it drops cylinder 3. Where would I find the misfire counters. I think I can find the o2 voltages tomorrow morning when its cold again and take some pictures.

Today I checked the earths and they are all good and clean.

I started the car about 40 minutes ago and as usual it runs, revs, everything clean until it dropped cylinder 3. I disconnected the coil pack on 3 and lifted it outside the engine and put an old plug inside and reconnected the wiring it sparked but it was coming out of the side of the spark plug and not reaching the electrode on the end. As I want to be honest hear, I put the new plugs straight in and did not gap them would this cause a problem? Before you ask, I did not drop them into the head I lowered them with my magnet and got a couple of turns on before I put the plug socket on. Please don't forget that coil pack 3 is firing but MISFIRING on 3.

Also when I go to Diagnose Process on my OBD I always select OTHER AREA is this correct? Because if I choose JAPAN AREA I get the message below.

It sounds like the coil pack rubber boot is tracking to earth, is it dirty, damaged or discoloured in any way? Any pictures?

Did you manage to get any freeze frame data when it started to misfire?

[flash22]

Compression is good, coil has been swapped still the same - were the injectors swapped positions ? a misfire code is just that, a generic code, you have continuity tested the wiring, but will it carry current

i will have to pull up some wiring diagram, is it a mk1 p10 or an early Mk2 P90 yaris

what engine is it ? 2szfe or the 1nrfe  ?

 

ps. these engines run like utter crap on anything other than Denso plugs