Author Topic: injectors not pulsing  (Read 42155 times)

Offline gsxrpig

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Re: injectors not pulsing
« Reply #25 on: January 13, 2017, 09:07:06 PM »
Or it is not sending the signal to the injectors because of a safety issue or sensor???
The temp sensor has been tested and results earlier....even though it is a bit out of spec(new one ordered) like Griffin said the computer would think it was cold and should be running a bit rich.  I have cut the wire to the warning light.
The TPS should be out of the equation on start up.
The AFM is what I will retest.
Does anyone have a way of bypassing the AFM to see if the bike will start?
  • Queensland, Australia
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Offline gsxrpig

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Re: injectors not pulsing
« Reply #26 on: January 13, 2017, 09:33:28 PM »
Ok.
AFM has thrown a issue up.
From Berts chart.
My AFM results.
Pin 7-5 59 changes with vane movement.
Reading very low there.
The rest are spot on.
pin 7-8 is 335 changes with vane
Pin 8-5 is 361 and constant.
Pin 8-9 is 202.
The rubber stop at the vane does seem worn and is not flat ...but I got no idea what it should look like.
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Offline The Mighty Gryphon

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Re: injectors not pulsing
« Reply #27 on: January 13, 2017, 10:15:49 PM »
Here is some bedtime reading that might help you understand how the L-Jetronic works.

 http://bowlsby.net/914/Classic/zTN_Man15.pdf

Personally, I am thinking the problem is either the signal from the ignition control unit or the air flow sensor.  It could be that the signal isn't there or there is a continuity problem in the wiring.

In any event, I would be double checking all the inputs to the ECU. 
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline gsxrpig

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Re: injectors not pulsing
« Reply #28 on: January 13, 2017, 10:29:56 PM »
Here is some bedtime reading that might help you understand how the L-Jetronic works.

 http://bowlsby.net/914/Classic/zTN_Man15.pdf

Personally, I am thinking the problem is either the signal from the ignition control unit or the air flow sensor.  It could be that the signal isn't there or there is a continuity problem in the wiring.

In any event, I would be double checking all the inputs to the ECU.
Thanks for the reply

So the test result on the AFM that I posted would that one difference be a cause do you think?
Continuity on wires is right.  But I will have to recheck all the Ignition readings again.  The electrician took the hall sensors out and tested them and they were working.  But I will rerun everything and let you know.
I have been reading about the L jetronic and have just downloaded some reading on the AFM.
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Offline Laitch

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Re: injectors not pulsing
« Reply #29 on: January 13, 2017, 11:26:49 PM »
In any event, I would be double checking all the inputs to the ECU. 
With the starter running, compare the Pin #8 value of your Ignition Control Unit/Electronic Ignition Module with Vogel's chart value: 10 to 20Mv. The fuel injection control unit needs an rpm signal for starting.
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Offline The Mighty Gryphon

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Re: injectors not pulsing
« Reply #30 on: January 13, 2017, 11:32:34 PM »
With the starter running, compare the Pin #8 value of your Ignition Control Unit/Electronic Ignition Module with Vogel's chart value: 10 to 20Mv. The fuel injection control unit needs an rpm signal for starting.

That is one of the signals I was thinking of.  I would go right to pin #1 on the ECU and make sure you have it.  If not, work back from there.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline gsxrpig

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Re: injectors not pulsing
« Reply #31 on: January 14, 2017, 01:05:56 AM »
I agree men.
It is a stinker here today...Saturday and the bike is at work.
Pretty sure the electrician checked it and pretty sure my shit multi meter won't measure that low in volts.
But i will report back.
If I am missing that signal am I presuming faulty ignition control?
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Offline The Mighty Gryphon

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Re: injectors not pulsing
« Reply #32 on: January 14, 2017, 01:50:02 AM »
You say the plugs were sparking,didn't you?  That would imply that the ignition module was doing that part of the job. 

You need to check the continuity of the wire from the ignition module to pin #1 of the ECU.  My Clymer manual says it is a red wire with a yellow stripe.  Clean the terminals at both ends.  If Laitch is right about the 20mv signal, it won't take much to lose it.

If the wire is ok, it may be possible that the ignition module has a problem putting out the signal to the ECU.  You will need to swap with a good module to confirm.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline gsxrpig

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Re: injectors not pulsing
« Reply #33 on: January 15, 2017, 07:07:52 PM »
Righto guys.
Borrowed a better multi meter.
I have continuity between pin 8 ignition and pin 1 ECU
reading 32mV  AC at pin 1 on the ECU when cranking.
Much higher than 10-20 mV on Berts list.
Any ideas?
Going to run the lot of tests again and double check my old results with the better meter.
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  • 90 k100LT

Offline gsxrpig

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Re: injectors not pulsing
« Reply #34 on: January 15, 2017, 09:35:02 PM »
The only measurements that are not in berts range .
On ignition module
pin 7 ground to FI relay with starter is giving 1.42 Volts (0 to 1 V on chart)
Pin 8 Signal is fluctuating from as high as 47 to 32 mV ac (10-20mV on chart)
*****Pin 10 with starter running I can not get a reading *****(1.5 to 4V on chart)
Pin 9 and 14 both supply 1.5 to 2 Volts with starter.
On ECU
Pin 1 from Ignition is the same 47 to 32mV
Pin 10 is only reading about 1220 resistance.  I took the sensor out and it was testing a bit high on the range.  Have ordered a new one.
Pin 12 injector test
1 injector is 15 ohms
2 injectors is 8 ohms
3 injectors is 5.2 ohms
4 injectors is 4 ohms,  so all pretty close.
My noid test lights turned up and as expected no pulsing at injectors, confirmed.

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Offline gsxrpig

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Re: injectors not pulsing
« Reply #35 on: January 15, 2017, 10:19:18 PM »
I am tracking that green and yellow sucker all over the place...something weird there.
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Offline The Mighty Gryphon

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Re: injectors not pulsing
« Reply #36 on: January 15, 2017, 11:59:17 PM »
Pin 10 on the ICU... You say you weren't reading anything there. 

With your meter black wire on ground and the red on terminal 10 what do you read with the ignition switch off?  Ignition switch on?  Starter cranking?

Have you checked fuse #1 and cleaned it's terminals?
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline gsxrpig

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Re: injectors not pulsing
« Reply #37 on: January 16, 2017, 12:26:45 AM »
Pin 10 on the ICU... You say you weren't reading anything there. 

With your meter black wire on ground and the red on terminal 10 what do you read with the ignition switch off?  Ignition switch on?  Starter cranking?

Have you checked fuse #1 and cleaned it's terminals?
Pin 10 ignition off is 0V
ignition on is 12.2 V
Cranking I get .2V in AC ...was getting nothing before??
Pin 9 and 14 at crank are giving 1.5 to 2 volts AC
I went back to my instrument wiring trying to trace the green/ yellow which turns into green black after the fuse.
Fuse is powering both sides.
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Offline The Mighty Gryphon

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Re: injectors not pulsing
« Reply #38 on: January 16, 2017, 08:44:40 AM »
Pins 9,10,and 14 supply battery voltage.  You should be taking readings on those pins on the 20V DC scale on your meter.  You shouldn't use the AC scale on those pins.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Laitch

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Re: injectors not pulsing
« Reply #39 on: January 16, 2017, 09:22:26 AM »
Do you still have an clutch switch? It may be shorted.

  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline gsxrpig

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Re: injectors not pulsing
« Reply #40 on: January 16, 2017, 05:22:37 PM »
Pins 9,10,and 14 supply battery voltage.  You should be taking readings on those pins on the 20V DC scale on your meter.  You shouldn't use the AC scale on those pins.
Mmmm.  I was going off Bert's list and it is saying Volts AC 1.5 to 4V with starter running.
I am a bit perplexed with that as well.
If I set to 20V DC
Pin9

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Offline gsxrpig

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Re: injectors not pulsing
« Reply #41 on: January 16, 2017, 05:25:10 PM »
Pins 9,10,and 14 supply battery voltage.  You should be taking readings on those pins on the 20V DC scale on your meter.  You shouldn't use the AC scale on those pins.
Whoops..I was going off Berts list
pin 9-10-14 Ground to primary coils...starter running...Volts AC 1.5 to 4V.
I am having trouble getting my head around that one.
If set on 20V DC
pin9   9.5-8.6V
Pin10 10V
Pin14   9.4 V.

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Offline gsxrpig

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Re: injectors not pulsing
« Reply #42 on: January 16, 2017, 05:43:02 PM »
Do you still have an clutch switch? It may be shorted.
Hey Laitch.
No I eliminated the instrument cluster but kept the neutral light with the 4 relay setup.
So have also eliminated the clutch switch with that.
I went back through my instrument wiring yeterday to double check everything and it seems ok.
I thought I was in the clear with the clutch and Gear positioning features from a post I had months ago with RBM and Inge K.
I replaced the switch blocks with GSXR ones.  So i used right hand switchblock wiring.
Green 12V feed to kill switch with Green and Yellow trace getting power with the kill switch off or RUN
Starter button is giving power to Black with yellow trace.to feed starter relay and ICU.
Thanks for the feedback.
The PO told me it was a runner before the fuel related issues.
So I am trying to believe him, and am thinking I have got something wrong in my wiring indeed.
I have removed the BMU and Flasher unit under past posts from forum members.
Along with removing the instrument panel and both switchblocks to fit the Gsxr front end I have put on.
So a lot of wiring changes have been made so I am happy to take the wrap for it If I can find it :dunno2:
Keep the ideas coming please...happy to test retest and experiment.
  • Queensland, Australia
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Offline Laitch

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Re: injectors not pulsing
« Reply #43 on: January 16, 2017, 07:14:25 PM »
Pins 9,10,and 14 supply battery voltage.  You should be taking readings on those pins on the 20V DC scale on your meter.  You shouldn't use the AC scale on those pins.
I understand gsxrpig's reasoning. It looks like Bert is calling for AC readings on pins 8,9,10 and 14, and gsxrpig's readings seem to be close to conforming.

* Ignition Control Unit chart extract.png (33.3 kB . 576x43 - viewed 450 times)

Take your AC reading at pin 8 on the ignition control module, just for grins, gp.  :yes
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline gsxrpig

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Re: injectors not pulsing
« Reply #44 on: January 16, 2017, 07:25:20 PM »
The way I read Bert's ICU chart he is calling for AC readings on pins 8,9,10 and 14.
These are my AC readings
Pin 10 ignition off is 0V[/size]ignition on is 12.2 VCranking I get .2V in AC ...was getting nothing before??Pin 9 and 14 at crank are giving 1.5 to 2 volts ACI went back to my instrument wiring trying to trace the green/ yellow which turns into green black after the fuse.Fuse is powering both sides.
Pin 10 on my bike is Green  yellow trace.
Which is giving me 12V but little AC under starter??
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Offline gsxrpig

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Re: injectors not pulsing
« Reply #45 on: January 16, 2017, 08:29:42 PM »
OK. just testing stuff as a last resort waiting for the golden reply. :2thumbup:
I disconnected the AFM.  The temp sensor and the TPS.
Crank the bike..
For the first time I get a light from my Noid test light.
It is not a pulse..it lights upon letting go of the start button?
Reconnect the AFM...light there.
Reconnect the tps....light there.
BUT connect the Temp sensor ....and the light disappears again.
I have terminated the violet with black trace wire that normally feeds the warning light on the dash.  But had thought this would cause no issue.
Sensor did respond to temperature change but was reading  in the high end f the resistance chart?
So still no pulse but maybe a point in the right direction??







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  • 90 k100LT

Offline Laitch

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Re: injectors not pulsing
« Reply #46 on: January 16, 2017, 09:07:23 PM »
These are my AC readings
Cranking I get .2V in AC ...was getting nothing before??
Which is giving me 12V but little AC under starter??

First off, I can't tell whether you are making statements or asking questions when you use question marks so—no loss to you—I'm going to drop out now because it's making my eyeballs throb.


But first:
Can we agree that your AC results for pins are within spec on Bert's chart 9,10, and 14?
Based on info you've provided, the only reading outside the chart's specification is the Pin 8 ignition module reading which is too high. Can we agree on that?

Is that "was getting nothing before??" a statement or question? It's an indecipherable statement in my book. I'm only concerned with what is happening now getting now.
"Which is giving me 12V but little AC under starter??" That is another puzzling sentence construction. I can't decipher that at all. It's too late for cafe cubano or I'd use that to translate. :giggles

"trying to trace the green/ yellow which turns into green black after the fuse." Where does the gn/sw wire go? Where does the ge/gr wire go?

It's an encouraging sign that you're getting a different reaction when something is disconnected, but using phrases like "reading on the high end of the chart" have no value to me. I need descriptions to be exact.





  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline kennybobby

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Re: injectors not pulsing
« Reply #47 on: January 16, 2017, 09:49:51 PM »
It sounds like you have a bad ground at the water temperature sensor.  Measure the resistance from the L-jetronic connector pin 10 to chassis/ground (while disconnected from the L-jet).

It should read a value close to that shown in the chart for your ambient air temperature, like a thermometer.  My guess is that you will have a very high resistance or no continuity at all--did you put teflon tape on the threads?

When you say you terminated the other wire from that sensor, how do you run the radiator fan now without that input to the temperature relay module that was in the ebox under the tank?
Ridin' 87 K75S vin 1334,
Renchin' 86 75S vin 0061

Offline Martin

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Re: injectors not pulsing
« Reply #48 on: January 16, 2017, 10:10:29 PM »

+1 Kenny looking like a bad earth or Teflon.
Regards Martin.
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Offline gsxrpig

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Re: injectors not pulsing
« Reply #49 on: January 16, 2017, 10:30:33 PM »
It sounds like you have a bad ground at the water temperature sensor.  Measure the resistance from the L-jetronic connector pin 10 to chassis/ground (while disconnected from the L-jet).

It should read a value close to that shown in the chart for your ambient air temperature, like a thermometer.  My guess is that you will have a very high resistance or no continuity at all--did you put teflon tape on the threads?

When you say you terminated the other wire from that sensor, how do you run the radiator fan now without that input to the temperature relay module that was in the ebox under the tank?
Hi Keenybobby thanks for the reply.  very helpful.
Reading 1164 at pin 10 with ecu disconnected.  About 35 degrees here today. But the bike would be a little lower in temperature.
Yes i did have thread tape on the sensor but removed it after the testing I did last week.  One thing was when I put the new O ring in the coolant pipe stub I put some gasket sealant on as well.  It had a bad leak when I bought the bike.  Maybe this is creating a ground issue.  But continuity to the ecu is good and back to the sensing sw unit in the wiring box is also good.
The wire I terminated was to the warning light.  the fan is still connected. the sensor is still connected to the sensing sw unit in the wiring box as well.  Got rid of the light as I have a gauge now.  I have tried hooking that wire back up to my led test light but nothing changes.
  • Queensland, Australia
  • 90 k100LT

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