f200txr Is not idling or running well, getting a code 29

[mokaction]

When out on the boat today to show it off to my mom. We took off from the local harbor and cruised around for a while. Boat was idling great, and then all of a sudden the ignitions started to skip. Thought it was a fuel problem, so rush back to the back of the boat to pump the fuel primer. Ignition skipping stopped. Then all of a sudden it started again, skipping and then stalled. I started it back up and it idled for about a second then stalled again. One last time starting it and got it idling, then throttling her up and she back fired and stalled. So I shut her down and turn on the kicker and got my mother and I back to the launch ramp.

Hooked up the YDS and got a code 29, but would this code cause my motor to do all this? If it was a carburetor motor it would have sounded like a fuel problem. I know a code 29 is an intake air pressure sensor. Below I will add the YDS results.

How often do these sensors go bad? Would this sensor also create this condition describe above?

Diagnosis
Code Item Result Condition
29 Intake press sensor Irregular Out of specification

Monitor Item Result Unit
Engine speed 0 r/min
Intake pressure 34.76 inHg
Atmospheric pressure 31.6 inHg
Battery voltage (12-16) 12.6 V
TPS voltage (0.5-4.5) 0.679 V
Throttle valve opening (-1-90) -0.5 deg
Fuel injection duration 0 ms
Ignition timing - deg
ISC valve opening 67 %
Engine temperature (below 248) 116 ?F
Intake temperature (below 158) 77 ?F
Oil pressure (below 122) 0 psi

 

[rodbolt]

Re: f200txr Is not idling or running well, getting a code 29

clear the code and retest,
sounds like you have a clogged VST or water in the fuel system.
an intake backfire,normally caused by a lean air/fuel mix, will set a code 29.

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Rodbolt,

Thx, 4 coming back to me so quickly, I was having a hard time sleep cause if this.

OK.. I figured out what a VST is Vapor Separator Tank. I will check and clean all filters today and let you know.

Thx again,

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Well I cleaned all the filters vst and also took of the intake air pressure sensor, and the ISC and cleaned them off with some carb cleaner. Put everything back together.

Not sure how to clear off codes from ecm, but deleted it from the yds records then turned off yds and then turn engine key back to the off postions.

Then turn back key to on, turn on computer and loaded YDS. Checked the records and got this:

Still getting error code 29?? How do I reset???




Diagnosis Record
Total hours of operation 882
Code Item Occurred
29 Intake press sensor 882.9

Engine Monitor
Monitor Item Result Unit
Engine speed 0 r/min
Intake pressure 115.05 kPa
Atmospheric pressure 1066.7 hPa
Battery voltage (12-16) 12.7 V
TPS voltage (0.5-4.5) 0.679 V
Throttle valve opening (-1-90) -0.5 deg
Fuel injection duration 0 ms
Ignition timing - deg
ISC valve opening 67 %
Engine temperature (below 248) 115 ?F
Intake temperature (below 158) 89 ?F
Oil pressure (below 122) 0 psi
Engine stop lanyard switch OFF
Shift position switch ON

 

[rodbolt]

Re: f200txr Is not idling or running well, getting a code 29

apearently you have the laptop and software.
click on F3 to delete the codes.
if the code reappears its active.
if its active check the sensor input voltage and the actual sensor resistance.
the first set of numbers you posted seemed funny because with the engine off your air pressure and intake pressure should be about the same.

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Rodbolt,

The other problem is the Yamaha Manuel duesn't show the Volt Value or Resistance Values. Can you please post them for me?? And if you have the instructions that would be great too.

thx in advance again,

Larry

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

I don't know if this is going to line up right, but here are the results for the month..

Question, what sensor is used to take Atmospheric Pressure readings???



10/5/2007 Org 10/14/2007 10/20/2007 10/21/2007
Monitor Item Result Unit Result Unit Result Unit Result Unit Result Unit
Engine speed 0 r/min 0 r/min 0 r/min 0 r/min 0 r/min
Intake pressure 100.15 kPa 100.15 kPa 100.15 kPa 117.97 kPa 115.05 kPa
Intake pressure 29.65 inHg 29.65 inHg 29.65 inHg 34.92 inHg 34.06 inHg
Atmospheric pressure 1001.5 hPa 1001.5 hPa 997.5 hPa 1066.7 hPa 1066.7 hPa
Atmospheric pressure 29.6 inHg 29.6 inHg 29.5 inHg 31.6 inHg 31.6 inHg

 

[rodbolt]

Re: f200txr Is not idling or running well, getting a code 29

I will have to get back to ya on that one
I dont keep manuals here at the house much.
best memory serves is the sensor is mounted on the upper port intake tract.
but with the engine off the two pressure readings should be the same.
its part of how the ECU monitors engine load and makes certain fuel and timing corrections.
intake pressure is kinda the inverse of engine vacum.
at or near WOT intake vacum is nearly equal to atmospheric pressure.
as in its almost non existent.
at idle you should see something like 12" Hg or so.
this would be the difference in pressure from the air side of the throttle plate and the cylinder side of the throttle plate.
thats why I said clear the code then see if its still an active code. an engine backfire due to a lean mix can cause a spike in intake pressure that the ECU will read as a fault due to the ECU mapping.

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Well I cleared the code 29 and it came back again. I did the test 5 time to make sure.

Looks like a bad intake air pressure sensor. I will have to order one now.

Also my Intake reading are way off I took off the sensor cleaned it out again. And cleaned all the wires and check the contections over and over. Cleared off the codes and came back again.

So time for a new sensor, ordering it now.

Larry

 

[rodbolt]

Re: f200txr Is not idling or running well, getting a code 29

before ya order the sensor make sure the 5V reference is there.
but your symtoms still dont describe a bad sensor.
best memory serves the 5 volt is the orange and the black wires.
if the sensor fails you "should" see a 900 RPM idle, ign timing locked at 10*BTDC and top speed cannot be reached.
however we do see failures that defy the text book.
just because the code is set does not mean the sensor is bad.
check for any mechanical failures that could create a faulty reading as well.

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Rodbolt, thx for the quick reply, yes, that is one thing I forgot to mention. Motor was idling at 900rpm.. As for BTDC is for the pulse and TPS sensor. Books says there is no change in BTDC, but here is a diffrence in ignition mapping. As like you said that is what is causing the back firing. Is the 5 volts coming from the ecm or the sensor it self? should I use a peak volt meter for this reading? If so do I need the wiring harnest to get the 5 volt reading?

In the Manuel, there was not test given for intake air presure sensor. Don't have the notes. Would you know where I can find them?? Or purchase them??

Larry

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Rodbolt, ??? You know I am also getting all kinds of changing reading with the atmosphere pressure and intake pressure. The motor key is on the ON position, but motor is not running. And the Atmosphere pressure and intake pressure reading are moving on the Engine Monitor/computer screen?? Is that normal??

also what kind of mechanical failures that could create a faulty reading????????????? Cleaned and changed all the fuel filters..


Larry

 

[rodbolt]

Re: f200txr Is not idling or running well, getting a code 29

the ECM supplys the 5 volt reference to the MAP sensor.
this sensor has a sealed reference point and monitors intake pressure.
the nifty trick is at key on it looks for barometric pressure to give the ECM an altitude reference before starting. after engine starting it no longer monitors barometric pressure as its really rare to have major altitude changes when boating.
I would make sure my 5 volt DC reference is good and stable before replacing a sensor.
the ECM is rather stupid and can only react to a feed back regaurdless of why the feed back is incorrect.
normal timing at idle on that motor is about TDC, most any sensor failure/out of range feed back will lock idle timing at 10*BTDC and the ECM may go into a default map.
a tip, the pulser coils are physically located 10 degrees before top dead center .
normal voltage feed back is between about 1 volt to about 4.5.
conditions that can affect the sensor? any vacum leak or a leaking intake valve. anything that will create abnormal pulses in the intake manifold area.
thats why a lean backfire can create issues with the sensor.
a quick run with the techmate set to dyn can isolate a cylinder vacum issue.
but the readings with engine off should be stable unless either input reference voltage is bad,wiring between sensor and ECM is bad or the sensor is failing.
with engine idleing you should see something in the range of12" pressure you can use ether a techmate or a more crude test with a vacum guage attached inlinewith the VST pressure regulator to aid in diagnostics.
but the ECU definatly sees an issue if engine intake pressure running is exceeding barometric pressure when running as its a physical impossibilty.
normal barometric pressure ranges between about 29.9 and 32.5 inHG.
your sensor should indicate about local baro pressure at key on, this can be checked with your local weather channel.
its a rather confusing terminology with MAP systems.
with carbs we simply read vacum and let it ride.
with EFI we are compareing Manifold Absolute pressure against brometric pressure.
means at idle intake pressure is low,normally in the 12" range. at WOT and full load intake pressure climbs to about barometric pressure as the throttle plates are completly open.
just dont let it confuse ya
at a normal idle you should have about 21 inches of vacum,very low pressure compared to the atmosphere. with a carb at WOT intake vacum will decrease to less than 5 inches. almost atmospheric pressure.
see how it works ?

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Here are the new reading while at idle.

Also what sensor is used to measure intake? and which to meassure Atmospheric???



Monitor Item Result Unit
Engine speed 902 r/min
Intake pressure 62.64 kPa
Intake pressure 18.11 inHg
Atmospheric pressure 1012.1 hPa
Atmospheric pressure 30 inHg
Battery voltage (12-16) 13.9 V
TPS voltage (0.5-4.5) 0.674 V
Throttle valve opening (-1-90) -0.5 deg
Fuel injection duration 2.43 ms
Ignition timing BTDC 1 deg
ISC valve opening 72 %
Engine temperature (below 120) 34 ?C
Engine temperature (below 248) 93 ?F
Intake temperature (below 70) 28.5 ?C
Intake temperature (below 158) 83 ?F
Oil pressure (below 842) 539.8 kPa
Oil pressure (below 122) 78.8 psi

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

OK.. I am really stumped..

I purchase the new intake air pressure sensor and installed it. Did the test again and I am still getting the same errors.

Cleaned all the filters, did a compression test and checked all Valve Clearance. All is to spec there.

I also check the spark plugs. They where black with carbon, black soft sooty carbon. I am not getting good spark. All 6 plugs had carbon on them.

Also wanted to check the wires for the intake air pressure sensor, but I was not sure the color code, the colors on mine are
pink/green, black, and orange.. Which color do I check for the voltage??? Also do I use a peak voltage meter or just a regular meter??

Do you think my ECM or ISC could be bad?? ISC gets hot to the touch?? I am ready to kill the motor. Not getting very much sleep..

Please help..

Larry

 

[rodbolt]

Re: f200txr Is not idling or running well, getting a code 29

imagine that. the sensor was not faulty.
I tried to tell you.
the five volt reference will be measured between the orange and black, like I described.
like I also described the baro(atmospheric) pressure is done by the ECU at key on and from then on it reads intake pressure.
its why I keep beating up on ya gotta understand how a speed density EFI system works or your sunk.
and yamaha did not invent it they all work the same.
your intake pressure is way to high.
it indicates a vacume leak, a shutter held open or an intake valve leak or possibly a severe restriction in the exhaust. could also be a leaking or sticking injector.
but your temp reading is way to cold. how long and how did you warm up the engine ?
ISC opening is to high, you may need to run it with the techmate installed and use the DYN function. I would start with a link and sync with the techmate and new plugs.
but your intake pressure is 5-6" to high.
there are lots of shortcuts to take but you must fully understand how it works and why the ECU does what it does.

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Rodbolt,

OK sorry for not know the terms. What is a??

1. ECU?
2. Techmate?
3. DYN function?

Also thx for taking the time to teach me. I am trying to understand. I wish I had the factory training manual. If you have the lit number I will see if I can purchase one. for a f200trxa, but till then would love to get this motor working for I can take my daughter diving before she gets to old.. LOL..

I do understand how the Baro works now /w your help. Like a venture valve. atmosphric pressure on the outside and lower pressure on the inside. Once the venture opens the pressure is allowed to increase or equlize to outside pressure.

Tomorrow I will rig up a wiring harness to check for voltage and report back. In the regular Yamah f225a service manual there is no test for intake air pressure sensor, yet, there is a test for the TPS that is like you discribed so I got confussed.

Say for the TPS we are looking for 5 v on orange and black wire.

So it is like the same for the intake air pressure sensor with I am now going to start abrrviating to IAPS.. Is there any reading for the Pink and Black wire for the IAPS???

Also will add a vacum guage attached inlinewith the VST pressure regulator too tomorrow. What is the pressure I am looking for in the vacum guage???

I ran the motor for about 2 mins. No enough to get it to warm up. It would stall out before then. here the the latest readings.

Monitor Item Result Unit
Engine speed 902 r/min
Intake pressure 62.64 kPa
Intake pressure 18.11 inHg
Atmospheric pressure 1012.1 hPa
Atmospheric pressure 30 inHg
Battery voltage (12-16) 13.9 V
TPS voltage (0.5-4.5) 0.674 V
Throttle valve opening (-1-90) -0.5 deg
Fuel injection duration 2.43 ms
Ignition timing BTDC 1 deg
ISC valve opening 72 %
Engine temperature (below 120) 34 ?C
Engine temperature (below 248) 93 ?F
Intake temperature (below 70) 28.5 ?C
Intake temperature (below 158) 83 ?F
Oil pressure (below 842) 539.8 kPa
Oil pressure (below 122) 78.8 psi

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Rodbolt,

I was also just thinking about what you said. Why is the intake pressure not the same as the atmosphric pressure??

And why is the intakepressure always higher then the atmosphric pressure when the engine is off??

It is like once I turn on the key the ECM picks up the atmosphric pressure then maybe a clog in the manifold is increasing the pressure and recording the intake pressure higher??

I will check these tube in the picture attached. And keep you posted.

Thx again for all the ideas.

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

OK.. I check out all the vaccum lines and clean out all the gunk in them. they were not restricted at all just dirty in side had the IAPS hooked up and took the wiring harness from the ISC off.

Got perfect pressures reading with my YDS on the IAPS and once I hooked up the ISC againt the pressure reading went wacko again.

So I thought to my self. why not try to start the motor. I put all the parts that I had hanging off back on and left the ISC off.

Motor Idle and ran perfectly warmed her up and she ran like a top.. I know the ISC has something to do with air fuel mixture and ignition to make the motor more fuel econical?

Here are the YDS reading for you guys to study..

 

[mokaction]

Re: f200txr Is not idling or running well, getting a code 29

Also is there a way to test the ISC besides using a YDS?? Yamaha Service Manual say to just use the YDS, but the YDS say the ISC is perfect???

Larry