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  #46  
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croitoru  croitoru is offline
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Updates:
Tried resistors - 82, 100 and 120 ohm; no difference.
Managed to rig the turbo gauge (don't ask...)..
Stationary - rev up to 4800 rpm, 10-12 psi boost
Moving - rev up to 2000-3000 rpm, 10-12 psi boost
Climbing - rev up to 1800-1900, 10 psi, then psi drops to about 7-8 and car holds usually speed, rpm and psi.
Boost leak or fuel starvation?

Last edited by croitoru; 5 Days Ago at 08:14 PM.
  #47  
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Don't forget that boost is conditioned by exhaust pressure .
Exhaust pressure than is conditioned by rpm .
You saying that when moving in 4-th and 5-th gear the engine revs up to 3000 rpm on flat road ???
Seems like from one of your previous post that engine wouldn't pass 2000 rpm in 4-th or 5-th .
Quote: " I can climb in 4th and 5th but at at steady ~2000 rpm and 60-80 kmph.... if it's to high will slow down then kick power back in and climb steady as long as it stays around 2000 rpm."

Last edited by amlav; 5 Days Ago at 09:08 PM.
  #48  
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Originally Posted by amlav View Post
Don't forget that boost is conditioned by exhaust pressure .
Exhaust pressure than is conditioned by rpm .
You saying that when moving in 4-th and 5-th gear the engine revs up to 3000 rpm on flat road ???
Seems like from one of your previous post that engine wouldn't pass 2000 rpm in 4-th or 5-th .
Quote: " I can climb in 4th and 5th but at at steady ~2000 rpm and 60-80 kmph.... if it's to high will slow down then kick power back in and climb steady as long as it stays around 2000 rpm."
Thanks for continuing to help with sage advice and critical thinking Amlav.
Yes - flat can rev in 4th and 5th past 3000 rpm...
Problem starts on climb, as per original post... even the slightest....
I'll take it for more runs tomorrow, just managed to rig up the turbo gauge late today...
Had a chat and a beer with my brother who's a physicist, he explained how the pulse signal interposes over the #1 12.5v.
My gut is that I have a boost leak, like a valve - everytime I hit 10 psi or thereabouts, the leak lets pressure out. if it was fuel, or limp, on flat wouldn't rev much past 2000 rpm...but it always seems to be governed by the 10 psi, no matter speed or rpm... I thought was rpm until I got a gauge... the only constant is psi...
I think I'll get a 1m silicone hose and connect in and out bypassing the intercooler.... short 5 k runs at 80k max....
What do you think?
R
  #49  
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Quote:
Originally Posted by croitoru View Post
Thanks for continuing to help with sage advice and critical thinking Amlav.
Yes - flat can rev in 4th and 5th past 3000 rpm...
Problem starts on climb, as per original post... even the slightest....
I'll take it for more runs tomorrow, just managed to rig up the turbo gauge late today...
Had a chat and a beer with my brother who's a physicist, he explained how the pulse signal interposes over the #1 12.5v.
My gut is that I have a boost leak, like a valve - everytime I hit 10 psi or thereabouts, the leak lets pressure out. if it was fuel, or limp, on flat wouldn't rev much past 2000 rpm...but it always seems to be governed by the 10 psi, no matter speed or rpm... I thought was rpm until I got a gauge... the only constant is psi...
I think I'll get a 1m silicone hose and connect in and out bypassing the intercooler.... short 5 k runs at 80k max....
What do you think?
R
Have you tested the resistance of the #1 injector sensor?
If you disconnect it, is there any change?
When I had a bad sensor I could get to 3,000rpm, just took a long time to get there. everything you are saying suggests a bad sensor.
The resistor in the place of the sensor normally does not work. It only works on a very limited number of very early XJ diesels with the very first type of Bosch computers. Yours is clearly not one of them.
Best you give up on all this BS trying other things & just get a replacement injector with a working sensor. Unless you have tested the sensor in yours & it has a resistance of around 80 to 100 ohms. I can find where you have done the resistance test. Just do it!
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Last edited by layback40; 4 Days Ago at 08:44 AM.
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  #50  
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layback 40, yes, it's earlier in the thread, I did that before starting the thread... I measured, its 119 ohm.
Would anyone happen to know where I can get a number 1?
I looked up other threads, couldn't find it at the Australian suppliers, and there's no details about the Polish supplier guy...
R
  #51  
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Quote:
Originally Posted by croitoru View Post
layback 40, yes, it's earlier in the thread, I did that before starting the thread... I measured, its 119 ohm.
Would anyone happen to know where I can get a number 1?
I looked up other threads, couldn't find it at the Australian suppliers, and there's no details about the Polish supplier guy...
R
Do a Facebook search for the VM group.
I still think you have an issue with it. Maybe there is a break in the wire some where. You should be able to go right back to the EMU behind the heater inside the jeep & make sure you have conductivity there. Everything you are posting is saying limp mode.
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  #52  
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http://www.ausjeepoffroad.com/forum/...d.php?t=154725

If you exausted all your fault finding avenues check the above link . Actualy I would start with this . Inexpensive and saves you money if your injector 1 is good but you not sure .
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Quote:
Originally Posted by amlav View Post
http://www.ausjeepoffroad.com/forum/...d.php?t=154725

If you exausted all your fault finding avenues check the above link . Actualy I would start with this . Inexpensive and saves you money if your injector 1 is good but you not sure .
Amlav - thank you so much.
Yes, I think I'm at the end of it.
Thank you so much for sharing and updating the thread you have originally created - the information is absolutely amazing - should be a sticky and should go on the VM Motori FB page! Both testing and rebuilding injector #1!!!
I have one question - would you please be able to give a bit more details (a screenshot of Google play would suffice) about the oscilloscope app? I get a few results and none looks quite like yours.
I have a second vehicle ( my trusty 4.0 ZJ tank) so I think I'll go down the route of rebuilding. I can't seem to find a replacement injector anywhere; want to put to good use the teachings you've imparted; I always like a challenge and learning something new.
Hat off, thank you again.
R
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Quote:
Originally Posted by layback40 View Post
Do a Facebook search for the VM group.
I still think you have an issue with it. Maybe there is a break in the wire some where. You should be able to go right back to the EMU behind the heater inside the jeep & make sure you have conductivity there. Everything you are posting is saying limp mode.
Thank you
You're probably right, darn it...
I did measure the loom and looks ok as per amlav prior established values at 7.2kohm
Unfortunately I gave up Facebook a while back - asked gf to have a looksie, only been able to find the original page and group of the VM manufacturer.
I'll have a closer scan. Thank you for the tip
R

Last edited by croitoru; 3 Days Ago at 05:45 PM.
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