85 ltd fuel system light comes on and bike dies.


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Goldenponyboy
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Motorcycle: 1985 gl1200 ltd edition

85 ltd fuel system light comes on and bike dies.

Post by Goldenponyboy »



Hello all. I am having problems with my bike dying and the fuel system light coming on. Its done this a few times before but I just figured it was because of the low voltage due to the stator not working right. I did the poor boy conversion and now I have 13.4 on the voltmeter when this happens so power should not be the issue. I swapped the relay out with one of the others. That had no effect. I topped it up as it was at 1/3 full but it still cut out again. It happened last weekend when it was really cold out, 3c/37f. All was going well but it kept dying. I was lucky to make it home. It ran sporadically and would sometimes not start right back up but would eventually. The bike only has 42,000 kms on it. I guess I could change the fuel filter. Cant find any direct replacements but have some leads on some that should work. I was thinking I could take out the fuel filter and blow it out and see what comes out of it. It runs good when it runs. It sure kills the confidence in the corners knowing that the bike could die mid lean. Any suggestions?
Travis


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Rednaxs60
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Re: 85 ltd fuel system light comes on and bike dies.

Post by Rednaxs60 »

Travis: love a mystery. You need to look at the ECU for an error code.

You mention the Fuel System light comes on and the motor stops. There are two Fuel lights. The Fuel System light indicates if there is a problem with the CFI system, has nothing to do with the fuel system. The Fuel System Light on these bikes is similar to the check engine light for a car. Next time this happens the ECU under the trunk should show an error code. Do not turn the key to off. Have a look at the ECU for the error code first. If you turn off the key the error code will be lost until the next occurrence. I would surmise that the culprit will be the Ns (crank sensor), only a guess at this time. No signal from the Ns sensor and the engine will immediately shut down. If it were the throttle position sensor, the motor would probably keep going but not very well - BTDT. If the TPS is too far out of spec, it will misfire. A misfire in this engine, firing a cylinder at the wrong time, will feel like the engine should stop. Had this happen to me on another '85 Limited Edition I resurrected and drove across Canada. Had installed a new TPS before the trip, but even so, it was faulty. Switched it out and all was well.

If it is the Ns sensor, this part is not available but I have a recommendation for it.

Other than this, not much else will make the engine shut down. The engine will operate if one of the Gr/Gl sensors is faulty. The same with the PB sensors under the shelter. Error codes will be generated.

An error code will be generated if one of the injectors on one circuit is faulty, but if the two injectors on the circuit are faulty the engine will stop. Honda did a good job of building redundancy into the CFI system.

The Fuel light is a low level fuel indicator.

Fuel filters that you can use: Hastings GF159/Beck Arnley 043-0897/Fram G3969/NAPA 3556/WIX 33556 May have to modify the fuel filter holder. have pics on how I did mine.

This should get you started. Check the Supplement for additional information.

Good luck.
"When you write the story of your life, don't let anyone else hold the pen"

Ernest
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Goldenponyboy
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Re: 85 ltd fuel system light comes on and bike dies.

Post by Goldenponyboy »

Rednaxs60 wrote: Sun Nov 15, 2020 10:31 pm Travis: love a mystery. You need to look at the ECU for an error code.

You mention the Fuel System light comes on and the motor stops. There are two Fuel lights. The Fuel System light indicates if there is a problem with the CFI system, has nothing to do with the fuel system. The Fuel System Light on these bikes is similar to the check engine light for a car. Next time this happens the ECU under the trunk should show an error code. Do not turn the key to off. Have a look at the ECU for the error code first. If you turn off the key the error code will be lost until the next occurrence. I would surmise that the culprit will be the Ns (crank sensor), only a guess at this time. No signal from the Ns sensor and the engine will immediately shut down. If it were the throttle position sensor, the motor would probably keep going but not very well - BTDT. If the TPS is too far out of spec, it will misfire. A misfire in this engine, firing a cylinder at the wrong time, will feel like the engine should stop. Had this happen to me on another '85 Limited Edition I resurrected and drove across Canada. Had installed a new TPS before the trip, but even so, it was faulty. Switched it out and all was well.

If it is the Ns sensor, this part is not available but I have a recommendation for it.

Other than this, not much else will make the engine shut down. The engine will operate if one of the Gr/Gl sensors is faulty. The same with the PB sensors under the shelter. Error codes will be generated.

An error code will be generated if one of the injectors on one circuit is faulty, but if the two injectors on the circuit are faulty the engine will stop. Honda did a good job of building redundancy into the CFI system.

The Fuel light is a low level fuel indicator.

Fuel filters that you can use: Hastings GF159/Beck Arnley 043-0897/Fram G3969/NAPA 3556/WIX 33556 May have to modify the fuel filter holder. have pics on how I did mine.

This should get you started. Check the Supplement for additional information.

Good luck.
Thanks Ernest. I will go for a ride on the next nice day and check for the error code. As well as look up those filters at lordco or whoever has them in stock. Would the cranks sensor be anything the cold weather would make worse? It did die out in the summer but I thought it was just the low voltage. I'll report back after another test ride.
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Re: 85 ltd fuel system light comes on and bike dies.

Post by Goldenponyboy »

Rednaxs60 wrote: Sun Nov 15, 2020 10:31 pm Travis: love a mystery. You need to look at the ECU for an error code.

You mention the Fuel System light comes on and the motor stops. There are two Fuel lights. The Fuel System light indicates if there is a problem with the CFI system, has nothing to do with the fuel system. The Fuel System Light on these bikes is similar to the check engine light for a car. Next time this happens the ECU under the trunk should show an error code. Do not turn the key to off. Have a look at the ECU for the error code first. If you turn off the key the error code will be lost until the next occurrence. I would surmise that the culprit will be the Ns (crank sensor), only a guess at this time. No signal from the Ns sensor and the engine will immediately shut down. If it were the throttle position sensor, the motor would probably keep going but not very well - BTDT. If the TPS is too far out of spec, it will misfire. A misfire in this engine, firing a cylinder at the wrong time, will feel like the engine should stop. Had this happen to me on another '85 Limited Edition I resurrected and drove across Canada. Had installed a new TPS before the trip, but even so, it was faulty. Switched it out and all was well.

If it is the Ns sensor, this part is not available but I have a recommendation for it.

Other than this, not much else will make the engine shut down. The engine will operate if one of the Gr/Gl sensors is faulty. The same with the PB sensors under the shelter. Error codes will be generated.

An error code will be generated if one of the injectors on one circuit is faulty, but if the two injectors on the circuit are faulty the engine will stop. Honda did a good job of building redundancy into the CFI system.

The Fuel light is a low level fuel indicator.

Fuel filters that you can use: Hastings GF159/Beck Arnley 043-0897/Fram G3969/NAPA 3556/WIX 33556 May have to modify the fuel filter holder. have pics on how I did mine.

This should get you started. Check the Supplement for additional information.

Good luck.
Also what is your fix for the Ns sensor? If it is that. If its an upgrade I might as well do it while I have the bike down for a bit.
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Rednaxs60
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Motorcycle: 1985 GL1200 LTD
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2012 Suzuki DL1000 VStrom (sold)
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: 85 ltd fuel system light comes on and bike dies.

Post by Rednaxs60 »

You need to know what the error code is first, then do the fix.

The fuel filter you will source will be larger than the OEM filter. This is my thread on the fuel filter replacement: viewtopic.php?f=5&t=33846

For the Ns sensor, it can be installed in either the upper or lower position, doesn't matter which for engine operation. If the Ns sensor is faulty, use a PG sensor part from an '85 Aspencade, P/N 30300-ML8-680. This has two sensors that will install quite nicely without any modification to the housing. You will have to change the connector where it plugs into the electrical harness. If this is the problem, I can give more direction later.
"When you write the story of your life, don't let anyone else hold the pen"

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Re: 85 ltd fuel system light comes on and bike dies.

Post by Goldenponyboy »

So I finally got around to the problem. Started the bike up and fully warmed it up. The temp bars were 2 from the top of the meter. I didn't even move the bike and it died. So I'm not sure when the codes would appear on the ECU if there was a fault. When I start it up all 5 of the LEDs come on for 1.5 seconds. Bike runs normal. But they don't do any blinking nor are they different from one another. When the bike dies I did notice that all 5 LEDs came on like as if the bike was just turned on again. The fuel system light on the dash comes on and it dies but no codes. Do I need to do something to get the fault code to appear?
I am going to change out the fuel filter I got last summer. Its tne beck arnley 043-0897. Will see if that helps. I miss riding the Goldwing.
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Rednaxs60
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2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: 85 ltd fuel system light comes on and bike dies.

Post by Rednaxs60 »

This is a bit odd. You've got fuel, spark and air.

The fuel system light should only come on when there is an issue with the CFI, has nothing to do with the fuel supply system. The code(s) will appear on the ECU as soon as engine stops, or if the code is not critical, when the engine is operating such as the TPS.

Is the rad fan operating when the engine temp is 2 bars from the top?

The only parts in the CFI system that will stop the engine is the Ns (crank) sensor, numbers 1 and 3 injectors - both, and 2 and 4 injectors - both. For all the other sensors, the ECU default is to a fixed fuel delivery and timing.

You need to keep the key in the "on" position to check for codes. As soon as you turn the key "off" you lose the error codes that should be generated if there is a fault.

If this happens when the bike is idling, not going anywhere, I would recommend taking the seat off and taking the ECU from under the rear trunk and place it on the rear fender so you can monitor the error code display better. Easy to not see a light when trying to peak under the rear trunk, and to be quick to turn the key to "off".

If there are no error codes the issue is not with the CFI and probably not with the fuel delivery system. If the bike operates up to operating temp, the fuel system pressure is probably good, could do a check of it. Would do this before starting a parts replacement process.

Fuel filter should be good.

Good luck.
"When you write the story of your life, don't let anyone else hold the pen"

Ernest
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Re: 85 ltd fuel system light comes on and bike dies.

Post by Goldenponyboy »

Rednaxs60 wrote: Mon Jan 18, 2021 9:05 pm This is a bit odd. You've got fuel, spark and air.

The fuel system light should only come on when there is an issue with the CFI, has nothing to do with the fuel supply system. The code(s) will appear on the ECU as soon as engine stops, or if the code is not critical, when the engine is operating such as the TPS.

Is the rad fan operating when the engine temp is 2 bars from the top?

The only parts in the CFI system that will stop the engine is the Ns (crank) sensor, numbers 1 and 3 injectors - both, and 2 and 4 injectors - both. For all the other sensors, the ECU default is to a fixed fuel delivery and timing.

You need to keep the key in the "on" position to check for codes. As soon as you turn the key "off" you lose the error codes that should be generated if there is a fault.

If this happens when the bike is idling, not going anywhere, I would recommend taking the seat off and taking the ECU from under the rear trunk and place it on the rear fender so you can monitor the error code display better. Easy to not see a light when trying to peak under the rear trunk, and to be quick to turn the key to "off".

If there are no error codes the issue is not with the CFI and probably not with the fuel delivery system. If the bike operates up to operating temp, the fuel system pressure is probably good, could do a check of it. Would do this before starting a parts replacement process.

Fuel filter should be good.

Good luck.
Yes is is odd. I was really looking forward to it being the Ns crank sensor. That is a simple thing and can be replaced.
OK so to answer your questions. Yes the rad fan does come on when it gets up in temp. The problem does happen when the bike sits there. I do not have to be driving it. I can see the ECU under the seat but I did have to lower its craddle so all 5 leds are visible. I have been down looking at the lights when it happens and there are no leds visble that stay on. If it just flutters then all the LEDs come on for 1.5 seconds and the bike continues to run. When it flutters like this the dash fuel system light comes on. The fuel light never comes on.
I changed the fuel filter today. Went as well as it could. Can no longer use the nice chrome cover that fit over the original. While warming up the bike fuel system light came on and the bike stalled. Started it up and it did the same thing and fluttered. Figured I would go for a ride to see whats up and it did not happen on the ride. But it is very cold out so I'm guessing this has something to do with high temps. It would not get close to the top two bars today it was so cold.
ON another note. CHeck out this Ltd. for sale over in Toronto. Only 20,000kms
https://toronto.craigslist.org/tor/mcy/ ... 19396.html
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2012 Suzuki DL1000 VStrom (sold)
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: 85 ltd fuel system light comes on and bike dies.

Post by Rednaxs60 »

Have another question. When this happens, does the engine have a miss or tries to fire on the wrong cylinder. This will feel like the engine wanting to come to an abrupt halt. You mention this happens at higher operating temps.

The reason I ask is that the TPS is sensitive to heat. I had this issue with a new aftermarket TPS on a different '85 Limited Edition that I resurrected and drove from Ontario back to BC on a couple of years ago. Replaced it with another new TPS half way across - had a spare with me, and all was well. The TPS is an integral key part of the system that has the lowest quality assurance controls.

I had this issue before I left Ontario, did not want to believe it, and had issues after I started the trip. Checked the fuel system with a fine tooth comb as well. The engine worked nicely at higher speeds and generally at lower speeds, but did not like the mid range where most of our riding is. had some very hard misfires that seemed to want to stop the engine.

I'd look at the TPS.

Took a look at the '85 in Toronto, nice looking bike, but rather expensive for the age. For this price the condition had better be close to perfect. Considering that people tend to shy away from these older FI models, it's a lot of money to ask. If it's in good shape$2K CDN would probably be better.

Good luck.
"When you write the story of your life, don't let anyone else hold the pen"

Ernest
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Re: 85 ltd fuel system light comes on and bike dies.

Post by Goldenponyboy »

Rednaxs60 wrote: Fri Jan 22, 2021 5:21 pm Have another question. When this happens, does the engine have a miss or tries to fire on the wrong cylinder. This will feel like the engine wanting to come to an abrupt halt. You mention this happens at higher operating temps.

The reason I ask is that the TPS is sensitive to heat. I had this issue with a new aftermarket TPS on a different '85 Limited Edition that I resurrected and drove from Ontario back to BC on a couple of years ago. Replaced it with another new TPS half way across - had a spare with me, and all was well. The TPS is an integral key part of the system that has the lowest quality assurance controls.

I had this issue before I left Ontario, did not want to believe it, and had issues after I started the trip. Checked the fuel system with a fine tooth comb as well. The engine worked nicely at higher speeds and generally at lower speeds, but did not like the mid range where most of our riding is. had some very hard misfires that seemed to want to stop the engine.

I'd look at the TPS.

Took a look at the '85 in Toronto, nice looking bike, but rather expensive for the age. For this price the condition had better be close to perfect. Considering that people tend to shy away from these older FI models, it's a lot of money to ask. If it's in good shape$2K CDN would probably be better.

Good luck.
No it does not have any weird abrupt halt feeling. It just flutters and dies or it may keep running. But eventually it dies. Any tips on where to get another TPS? Or how to test the TPS? I'll have a look in the manual and see what it says. I web searched for a TPS for sale but it doesnt look like any new ones are for sale. I wonder if I knocked it when I was installing the poor boy conversion.
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2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: 85 ltd fuel system light comes on and bike dies.

Post by Rednaxs60 »

Testing procedure is in the Supplement, starts on page 10-24. You can splice into the wires and make a test tap that will be permanently installed. I did this and used enough wire to tuck them out of the way beside the air filter.

Check the TPS setting. Make sure it is in spec. When/if you test the TPS to make sure it is calibrated to what is in the manual, there is a stop screw on the left side. Do not move it. Bring the throttle linkage to this stop screw - take note of the number of turns to bring the throttle linkage to the stop screw, need for after when you restart the engine.

You will have to use an aftermarket TPS, or buy an air chamber with one attached - least expensive way to get an OEM TPS. Since you have done the external alt mod, the aftermarket TPS has to be modified to fit. You can use a dremel to cut a slot in the OEM bolts, come out easy after this and/or you can turn the TPS to calibrate it. If you use an aftermarket TPS such as this for an early model Honda:


you will have to modify the housing to fit in behind the alternator. Here is a picture of the aftermarket TPS ready to be installed:


Tight fit behind the alternator. Don't be afraid to modify the TPS housing, works fine afterwards. You will have to modify the TPS arm so it engages the Throttle linkage. I drilled a very small hole in the TPS arm, used a small screw and JB weld to stiffen the screw:


This worked well. Have to be inventive.

I have noticed on my'85 Limited Edition that I can make the Fuel System light come on and go off while calibrating the TPS. The TPS can be just on the edge and while the engine is operating, and go back into range when the engine is stopped.

Read the error codes again. The Ns (crank) sensor could be faulty after all these years. When overheated and/or failing, can send a wrong signal or no signal and the engine shuts down. The sensor cools down, sort of a reset, then you can start the engine again. If the Ns sensor is just on the edge, doesn't take much for the ECU to shut down the engine, but the sensor could go back into spec very quickly and no error code would show up. You can check the resistance of the Ns sensor, and if you do, I would use a heat gun to simulate the temps it is working at. Can't hurt to change this one out for the one I recommended.

Still puzzled about the stopping and no error codes. Have you done a fuel system pressure test? The fuel pump could be heating up and stop pumping fuel. Static and dynamic pressures are in the supplement.

The troubleshooting chart in the Supplement Chapter 10, indicates that the primary causes of engine stalling, which is what is happening, are:

Fuel pressure
PB sensors - attached above the coils - have an alternative replacement solution for this - I have done this change

After these you get into plugs, air leaks and such.

Regarding the PB sensors: Looked into the various sensors that are on the fuel injection system. Did a lot of research and on the CX500-650 forum, there was information regarding the PB (MAP) sensors and how these affect the system below 3000 RPM. The vacuum that the PB sensor(s) monitor is at maximum around the 3000 RPM range. Once the engine RPM is past 3000 RPM the PB sensor(s) are no longer in play. This forum found that the Suzuki MAP sensor: Brand: Denso. Type number: 100798-5630. Suzuki number: 15620-35F00. Suzuki description: Sensor Boost, IAP (Inlet Air Pressure) sensor.

Here are some numbers regarding the OEM PB sensor and the Suzuki sensor. These sensors are very close in operation. First VDC is for the Suzuki sensor, the second VDC is for the OEM sensor. Read in four columns.

Suzuki Sensor/OEM Sensor

Inch of Hg/VDC/VDC/Delta

0/3.45/3.63/0.18
5/3.1/3.14/0.04
10/2.65/2.59/-0.06
15/2.18/2/-0.18
20/1.73/1.43/-0.3
25/1.26/0.88/-0.38

I took the temp of the engine operating to determine what the range was for each bar on the temp gauge and when the fan came on and off. Normal operating temp in bars for solo riding, 4 showing, can go up to six if sitting for a while. Two up riding, not too hilly, generally 4 bar range, may go in and out of the 5 bars. Going up hill, two up, mostly 5 bars showing.

The temperatures I took with a thermal imaging temp pistol are:

1 Bar: 41.6 deg C (106.9 deg F)
2 Bar: 46.8 deg C (116.2 deg F)
3 Bar: 55.3 deg C (131.4 deg F)
4 Bar: 68.1 deg C (154.6 deg F)
5 Bar: 90.5 deg C (194.9 deg F)
6 Bar: 98.1 deg C (208.6 deg F)

Fan on at 103.3 deg C (217.9 deg F)
Fan off at 92.7 deg C (198.6 deg F)

This is a mystery, you will find the issue.

Been investigating and checking items for a while.

Good luck.
"When you write the story of your life, don't let anyone else hold the pen"

Ernest
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Goldenponyboy
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Motorcycle: 1985 gl1200 ltd edition

Re: 85 ltd fuel system light comes on and bike dies.

Post by Goldenponyboy »

Rednaxs60 wrote: Sat Jan 30, 2021 11:00 pm Testing procedure is in the Supplement, starts on page 10-24. You can splice into the wires and make a test tap that will be permanently installed. I did this and used enough wire to tuck them out of the way beside the air filter.

Check the TPS setting. Make sure it is in spec. When/if you test the TPS to make sure it is calibrated to what is in the manual, there is a stop screw on the left side. Do not move it. Bring the throttle linkage to this stop screw - take note of the number of turns to bring the throttle linkage to the stop screw, need for after when you restart the engine.

You will have to use an aftermarket TPS, or buy an air chamber with one attached - least expensive way to get an OEM TPS. Since you have done the external alt mod, the aftermarket TPS has to be modified to fit. You can use a dremel to cut a slot in the OEM bolts, come out easy after this and/or you can turn the TPS to calibrate it. If you use an aftermarket TPS such as this for an early model Honda:Aftermarket TPS 1.jpgyou will have to modify the housing to fit in behind the alternator. Here is a picture of the aftermarket TPS ready to be installed:TPS Mod for alt mod install.jpgTight fit behind the alternator. Don't be afraid to modify the TPS housing, works fine afterwards. You will have to modify the TPS arm so it engages the Throttle linkage. I drilled a very small hole in the TPS arm, used a small screw and JB weld to stiffen the screw:TPS Arm Mod Distance.jpg This worked well. Have to be inventive.

I have noticed on my'85 Limited Edition that I can make the Fuel System light come on and go off while calibrating the TPS. The TPS can be just on the edge and while the engine is operating, and go back into range when the engine is stopped.

Read the error codes again. The Ns (crank) sensor could be faulty after all these years. When overheated and/or failing, can send a wrong signal or no signal and the engine shuts down. The sensor cools down, sort of a reset, then you can start the engine again. If the Ns sensor is just on the edge, doesn't take much for the ECU to shut down the engine, but the sensor could go back into spec very quickly and no error code would show up. You can check the resistance of the Ns sensor, and if you do, I would use a heat gun to simulate the temps it is working at. Can't hurt to change this one out for the one I recommended.

Still puzzled about the stopping and no error codes. Have you done a fuel system pressure test? The fuel pump could be heating up and stop pumping fuel. Static and dynamic pressures are in the supplement.

The troubleshooting chart in the Supplement Chapter 10, indicates that the primary causes of engine stalling, which is what is happening, are:

Fuel pressure
PB sensors - attached above the coils - have an alternative replacement solution for this - I have done this change

After these you get into plugs, air leaks and such.

Regarding the PB sensors: Looked into the various sensors that are on the fuel injection system. Did a lot of research and on the CX500-650 forum, there was information regarding the PB (MAP) sensors and how these affect the system below 3000 RPM. The vacuum that the PB sensor(s) monitor is at maximum around the 3000 RPM range. Once the engine RPM is past 3000 RPM the PB sensor(s) are no longer in play. This forum found that the Suzuki MAP sensor: Brand: Denso. Type number: 100798-5630. Suzuki number: 15620-35F00. Suzuki description: Sensor Boost, IAP (Inlet Air Pressure) sensor.

Here are some numbers regarding the OEM PB sensor and the Suzuki sensor. These sensors are very close in operation. First VDC is for the Suzuki sensor, the second VDC is for the OEM sensor. Read in four columns.

Suzuki Sensor/OEM Sensor

Inch of Hg/VDC/VDC/Delta

0/3.45/3.63/0.18
5/3.1/3.14/0.04
10/2.65/2.59/-0.06
15/2.18/2/-0.18
20/1.73/1.43/-0.3
25/1.26/0.88/-0.38

I took the temp of the engine operating to determine what the range was for each bar on the temp gauge and when the fan came on and off. Normal operating temp in bars for solo riding, 4 showing, can go up to six if sitting for a while. Two up riding, not too hilly, generally 4 bar range, may go in and out of the 5 bars. Going up hill, two up, mostly 5 bars showing.

The temperatures I took with a thermal imaging temp pistol are:

1 Bar: 41.6 deg C (106.9 deg F)
2 Bar: 46.8 deg C (116.2 deg F)
3 Bar: 55.3 deg C (131.4 deg F)
4 Bar: 68.1 deg C (154.6 deg F)
5 Bar: 90.5 deg C (194.9 deg F)
6 Bar: 98.1 deg C (208.6 deg F)

Fan on at 103.3 deg C (217.9 deg F)
Fan off at 92.7 deg C (198.6 deg F)

This is a mystery, you will find the issue.

Been investigating and checking items for a while.

Good luck.
So I had not touched the bike since the last trip where it kept dying. Its been too cold and wet to go for a ride until yesterday so I started it up and worked around the garage and was waiting for it to sputter out and stall. But it didnt. It kept running. So I got geared up and went for a ride around the block. It kept running. Then I went to my buddies and he was at work so I went to his work on the other side of the city. It kept running. I rode for a couple hours and nothing went wrong. I love riding this bike. I wonder if its a cold thing. It was really cold the last time I rode it. The mystery continues.


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