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I had an issue once where the DME was grounding one of the reference sensor signals when plugged in (signal was fine at harness when not plugged in). Turned out to be an issue with the sensor metal casing--in other words, on outside random issue, not DME/ECU
its not a signal its just a plain old 12v+ supply .They are identical The only difference between them is that T30 is live all the time and T86 is only live when the ignition is switched on
Ahhh I see. I don’t get it either. Keep in mind the car will start when the relay is plugged in.
Also an an important note it’s behaving the same way it did with the other test DME Rich loaned me.
Its also important to note that the DME in the car right now is the original one to my car. It’s the same one that was causing the car to flood and smoke etc.
He replaced the chip that monitors all the voltages coming in from the sensors in both DMEs and that’s all he did to them.
And with everything plugged in Relay included the car starts and runs extremely well. It’s only now after some time that it shuts off power to the fuel pump.
Not sure if theres any clues there but hopefully that’s a little more clear of what’s happening.
Ahhh I see. I don’t get it either. Keep in mind the car will start when the relay is plugged in.
And with everything plugged in Relay included the car starts and runs extremely well. It’s only now after some time that it shuts off power to the fuel pump.
Not sure if theres any clues there but hopefully that’s a little more clear of what’s happening.
I hope you don’t mind but I break my back everytime I have to get in there and plug it and un plug it lol. So I made a quick example real fast to show you what’s in there. It’s the same exact thing just without crimp connectors on it.
Threw the 911 in there for good luck lol. Lost my work space to another project with my brother lol.
As for the relay itself, if you want to play tonight, gently pull these two tabs apart and pull the guts out
Check to see if there are any cracks in the solder joints and wear or dirt on the moving contact. The little video in my linked album shows the contact point; rub some paper between it and spray some contact cleaner if you have it:
As for the relay itself, if you want to play tonight, gently pull these two tabs apart and pull the guts out
Check to see if there are any cracks in the solder joints and wear or dirt on the moving contact. The little video in my linked album shows the contact point; rub some paper between it and spray some contact cleaner if you have it:
Will do. And I hope the grounding issue is what’s happening. I used the same metal shroud that the crank sensor slides into. I read that if I didn’t, then I would get severe kick back on startup due to interference between the two sensors
I hope you don’t mind but I break my back everytime I have to get in there and plug it and un plug it lol. So I made a quick example real fast to show you what’s in there. It’s the same exact thing just without crimp connectors on it.
Threw the 911 in there for good luck lol. Lost my work space to another project with my brother lol.
Looks fine.. unless there's some weird electrical reason why it's different combining all three leads together externally (as opposed to the daisy chain you got there)
Will do. And I hope the grounding issue is what’s happening. I used the same metal shroud that the crank sensor slides into. I read that if I didn’t, then I would get severe kick back on startup due to interference between the two sensors
Note that I am *not* suggesting you have a reference sensor grounding issue (I believe you're using Bosch sensors so that shouldn't be the case, and the issue I had wasn't the bracket shield but the outside metal part on the aftermarket sensor itself).
I'm only suggesting a test of sorts to see if the sensor(s) signal(s) are present up to the harness as well as when plugged into the DME. In my case, the DME, upon noticing something incorrect, grounded & shut down the sensor signal.
When you're using terminal 30, Does the DME see something weird and shut down a sensor signal?
Note that I am *not* suggesting you have a reference sensor grounding issue (I believe you're using Bosch sensors so that shouldn't be the case, and the issue I had wasn't the bracket shield but the outside metal part on the aftermarket sensor itself).
I'm only suggesting a test of sorts to see if the sensor(s) signal(s) are present up to the harness as well as when plugged into the DME. In my case, the DME, upon noticing something incorrect, grounded & shut down the sensor signal.
When you're using terminal 30, Does the DME see something weird and shut down a sensor signal?
But, right now it seems more a relay issue
I honestly have no clue what the DME is seeing that might cause it to shut down the pump or shut down spark when using terminal 30.
I made my best effors to take some pictures of the relay without the casing but it’s pretty difficult to see any lines. At least for my untrained eye.
I honestly have no clue what the DME is seeing that might cause it to shut down the pump or shut down spark when using terminal 30.
I made my best effors to take some pictures of the relay without the casing but it’s pretty difficult to see any lines. At least for my untrained eye.
This looks highly suspect to me
Looks like a line directly down the pin that if I’m not mistaken, is actually the pin for 86. It’s PIN number 3 on the bottom of the relay but that doesn’t correspond with any of the numbers I’m familiar with lol.
When you're using terminal 30, Does the DME see something weird and shut down a sensor signal?
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Dan .......terminal 30 is just the common 12v+ supply direct from the positive terminal of the battery that feeds most things on the fuse relay box including the DME relay. The ECU doesn't monitor it its just an unswitched 12v+ supply which is why I cannot see how it could have any bearing on the speed sensor output or the tach bounce.
I suspect that it was just a coincidence but it really should be checked again for confirmation before anything further is done
Dan .......terminal 30 is just the common 12v+ supply direct from the positive terminal of the battery that feeds most things on the fuse relay box including the DME relay. The ECU doesn't monitor it its just an unswitched 12v+ supply which is why I cannot see how it could have any bearing on the speed sensor output or the tach bounce.
I suspect that it was just a coincidence but it really should be checked again for confirmation before anything further is done
For sure, it makes little sense, but neither did my issue until someone who spent a year on the same matter discovered the solution completely by fluke! It followed no logic to test for what he tested to find it. An entire year of logical testing and nothing. Crazy.
I agree that another look to confirm the lack of tach bounce is in order. But if that's the case, I would test and see just where the sensor signal disappears, perhaps even inside the DME/ECU
personally I would not recommend any further fiddling inside the ECU until all other tests have been inconclusive. Its all too easy to do unknown damage inside the ECU where many components work on as little as 1.5volts
The more components that are randomly fiddled with adjusted or replaced the more difficult it becomes to troubleshoot a fault because in the end you cannot trust that anything is working correctly.
one thing we can assume is that all of these components did not suddenly simultaneously fail at the same time so it makes no sense whatsoever to substitute , adjust, modify and alter settings and components throughout the fuel injection system.
04-02-2019, 06:50 PM
