Only 2 injectors getting a pulse from ECU. EVO 6
Discussion
I have a problem with my EVO 6 in which im not getting a signal to injectors 3 and 4 from the ecu..
I have checked;
12v to the Injectors.
continuity from the the earth wire to the ECU
swapped the injectors around to dismiss faulty injectors
Grounds from engine/inlet manifold
Injector transistor box measuring OHMS and they are the same across all 4pins
I have replaced the ECU
Other things that i thought was possible was crank/ cam sensor but I would not be getting a spark, which I'am to all 4 coils..
The engine will run try to run on the 2 cylinders 1 and 2 every so often
Anyone with advice or experienced this before? Beer tokens for the winner as Im now lost and almost at losing it with this car
I have checked;
12v to the Injectors.
continuity from the the earth wire to the ECU
swapped the injectors around to dismiss faulty injectors
Grounds from engine/inlet manifold
Injector transistor box measuring OHMS and they are the same across all 4pins
I have replaced the ECU
Other things that i thought was possible was crank/ cam sensor but I would not be getting a spark, which I'am to all 4 coils..
The engine will run try to run on the 2 cylinders 1 and 2 every so often
Anyone with advice or experienced this before? Beer tokens for the winner as Im now lost and almost at losing it with this car
Krikkit said:
Have you any access to a scope? It'd be interesting to see if the resistor pack is really OK by watching the pulses from both sides and coming from the ECU...
A scope ? I've only got a multi meter, i checked resistance on the resistor and its comes back slightly above manufacture spec across 4 specs, all of them being exactly the same readingAlso checked the pulse out of the 2 injector plugs and nothing whereas the the 2 that are fine are registering with my test light.
I'm really stuck with this one
Mr2Mike said:
What is this "injector transistor box"? Does the ECU not drive the injectors directly?
they use low impedance injectors and a resistor pack.Resistor pack on the bulkhead is likely fried, there are 4 resistors in the pack, 1 for each injector line.
It's on the 12v line to the injectors as far as I recall.
Presumably the ecu is sending a signal to all 4 injectors despite the thread title, but they wont operate without the power supply via the pack.
stevieturbo said:
Mr2Mike said:
What is this "injector transistor box"? Does the ECU not drive the injectors directly?
they use low impedance injectors and a resistor pack.Resistor pack on the bulkhead is likely fried, there are 4 resistors in the pack, 1 for each injector line.
It's on the 12v line to the injectors as far as I recall.
Presumably the ecu is sending a signal to all 4 injectors despite the thread title, but they wont operate without the power supply via the pack.
I can get a pulse directly out of the ecu using the same method from the 2 same injectors.
I've also tested resistance from the resistor pack and all 4 are good ohm readings...
stevieturbo said:
What sort of test light, and exactly how are you testing ?
Testing the pulse from the ECU ? Take the plug off the injector, place a lead from test light into the earth plug coming from ecu then put a positive on the other lead to the battery.. On the good injectors there is a clear pulse.As I've said in other posts I've tested for 12v supply to all injectors and they are all getting power fine with ignition turned on and also while turning the engine over.
Just for clarity.
There is no "earth line" to the ecu. There is an ecu trigger that will be grounded to energise the injector and this will rise to 12v to de-energise the injector.
So be sure you are actually on the actual trigger wire when testing for a trigger. And use a known solid 12v supply for the test, not the injector 12v supply.
Likewise when testing that 12v supply via resistor pack. Ensure you're testing to a good known ground
But from what you are saying the only sensible explanation is the injector drivers in the ecu are fried.
I'd say the resistor pack is more likely to be dead, but everything you are saying suggests the ecu.
There is no "earth line" to the ecu. There is an ecu trigger that will be grounded to energise the injector and this will rise to 12v to de-energise the injector.
So be sure you are actually on the actual trigger wire when testing for a trigger. And use a known solid 12v supply for the test, not the injector 12v supply.
Likewise when testing that 12v supply via resistor pack. Ensure you're testing to a good known ground
But from what you are saying the only sensible explanation is the injector drivers in the ecu are fried.
I'd say the resistor pack is more likely to be dead, but everything you are saying suggests the ecu.
stevieturbo said:
Just for clarity.
There is no "earth line" to the ecu. There is an ecu trigger that will be grounded to energise the injector and this will rise to 12v to de-energise the injector.
So be sure you are actually on the actual trigger wire when testing for a trigger. And use a known solid 12v supply for the test, not the injector 12v supply.
Likewise when testing that 12v supply via resistor pack. Ensure you're testing to a good known ground
But from what you are saying the only sensible explanation is the injector drivers in the ecu are fried.
I'd say the resistor pack is more likely to be dead, but everything you are saying suggests the ecu.
Stevie,There is no "earth line" to the ecu. There is an ecu trigger that will be grounded to energise the injector and this will rise to 12v to de-energise the injector.
So be sure you are actually on the actual trigger wire when testing for a trigger. And use a known solid 12v supply for the test, not the injector 12v supply.
Likewise when testing that 12v supply via resistor pack. Ensure you're testing to a good known ground
But from what you are saying the only sensible explanation is the injector drivers in the ecu are fried.
I'd say the resistor pack is more likely to be dead, but everything you are saying suggests the ecu.
Firstly your advice is hugely appreciated
I've tested resistor pack and I get 6.8ohm across all 4 wires which I've been told is fine and what is expected. I've also got the pinouts from the ecu and know which is the earth/trigger
Everyone I've spoken to has said ECU including a auto electrician friend. I also expected ECU after running all these tests.
But.... I bought a ecu yesterday, received it today and the problem persists, exactly the same problem.. Another faulty ECU ? Unlikely I think
Also to add this is a replacement engine as my last engine went bang on cylinder 4 which just happens to be one of the cylinders not getting fuel, coincidence...?
Marks4g said:
Stevie,
Firstly your advice is hugely appreciated
I've tested resistor pack and I get 6.8ohm across all 4 wires which I've been told is fine and what is expected. I've also got the pinouts from the ecu and know which is the earth/trigger
Everyone I've spoken to has said ECU including a auto electrician friend. I also expected ECU after running all these tests.
But.... I bought a ecu yesterday, received it today and the problem persists, exactly the same problem.. Another faulty ECU ? Unlikely I think
Also to add this is a replacement engine as my last engine went bang on cylinder 4 which just happens to be one of the cylinders not getting fuel, coincidence...?
If the cylinder was getting no fuel, it would be difficult for any harm to come to that cylinder.Firstly your advice is hugely appreciated
I've tested resistor pack and I get 6.8ohm across all 4 wires which I've been told is fine and what is expected. I've also got the pinouts from the ecu and know which is the earth/trigger
Everyone I've spoken to has said ECU including a auto electrician friend. I also expected ECU after running all these tests.
But.... I bought a ecu yesterday, received it today and the problem persists, exactly the same problem.. Another faulty ECU ? Unlikely I think
Also to add this is a replacement engine as my last engine went bang on cylinder 4 which just happens to be one of the cylinders not getting fuel, coincidence...?
Clearly there is more to this problem than you're telling..
So was this problem identical on the last engine ? What exactly happened the engine ? Is the replacement engine known to be good ?
Has this new engine ever run correctly ?
And regarding the tests, there either is or isnt a signal and power supply. If there is, the injectors will be firing. If there isnt there wont.
Pull the manifold, rails, whatever and spin the engine over with injectors visible to see if they are actually spraying fuel on all cylinders.
Having seen the resistor pack fail before on an Evo 8, I'm still going to say this is the most likely problem especially after trying another ecu.
Assuming the 6 is the same as an 8 of course, havent worked around a 6.
Edited by stevieturbo on Wednesday 23 December 23:48
To test the 12v supply at the injector plug....and ensuring it is the 12v line and not the wire from the ecu, use a proper test lamp with an inductive load.
ie a 5w bulb or something, maybe even something a bit brighter.
Something to place a proper load on that supply that simply measuring resistance across the injector pack isnt highlighting
ie lamp between the 12v supply at each injector and battery ground.
ie a 5w bulb or something, maybe even something a bit brighter.
Something to place a proper load on that supply that simply measuring resistance across the injector pack isnt highlighting
ie lamp between the 12v supply at each injector and battery ground.
stevieturbo said:
If the cylinder was getting no fuel, it would be difficult for any harm to come to that cylinder.
Clearly there is more to this problem than you're telling..
So was this problem identical on the last engine ? What exactly happened the engine ? Is the replacement engine known to be good ?
Has this new engine ever run correctly ?
And regarding the tests, there either is or isnt a signal and power supply. If there is, the injectors will be firing. If there isnt there wont.
Pull the manifold, rails, whatever and spin the engine over with injectors visible to see if they are actually spraying fuel on all cylinders.
Having seen the resistor pack fail before on an Evo 8, I'm still going to say this is the most likely problem especially after trying another ecu.
Assuming the 6 is the same as an 8 of course, havent worked around a 6.
The engine came out of a low mileage car from a trusted EVO breaker and was said be to working well and healthy. The engine that went pop had no issues with fueling, I've only just discovered this fault after changing the engine over along with my original inlet manifold and injectors ect. Clearly there is more to this problem than you're telling..
So was this problem identical on the last engine ? What exactly happened the engine ? Is the replacement engine known to be good ?
Has this new engine ever run correctly ?
And regarding the tests, there either is or isnt a signal and power supply. If there is, the injectors will be firing. If there isnt there wont.
Pull the manifold, rails, whatever and spin the engine over with injectors visible to see if they are actually spraying fuel on all cylinders.
Having seen the resistor pack fail before on an Evo 8, I'm still going to say this is the most likely problem especially after trying another ecu.
Assuming the 6 is the same as an 8 of course, havent worked around a 6.
Edited by stevieturbo on Wednesday 23 December 23:48
I've never heard it running on 4 cylinders only on 2 due to this fueling problem, I'm only going by word from a trusted evo breaker.
I've had the fuel rail off and can visually see only 2 injectors spraying. I've also swapped the injectors around to ensure it wasn't a injector fault.
stevieturbo said:
To test the 12v supply at the injector plug....and ensuring it is the 12v line and not the wire from the ecu, use a proper test lamp with an inductive load.
ie a 5w bulb or something, maybe even something a bit brighter.
Something to place a proper load on that supply that simply measuring resistance across the injector pack isnt highlighting
ie lamp between the 12v supply at each injector and battery ground.
I have determined which wire is 12v feed and what wire is running to the ecu. The 12v feed to all 4 injectors according to my multi-meter are what they should be at 12v, and when the engine is turning over the faults drop..ie a 5w bulb or something, maybe even something a bit brighter.
Something to place a proper load on that supply that simply measuring resistance across the injector pack isnt highlighting
ie lamp between the 12v supply at each injector and battery ground.
Come on, this isn't a difficult problem to fault find!
The circuit goes:
Battery positive
Power relay
Injector series resistors
Injector
Ecu ( low side open collector driver)
Ground.
Hence without injectors on, you should see vbatt at each ecu input pin
With injectors on, you'd expect roughly half vbatt across the injector and half across the resistor box ( you'd also expect a small (<1volt) saturation voltage across the ecu driver
As a first check, with KOEO, use a paper clip carefully inserted from rear of ecu plug to short each injector wire to ground. This should energise each injector with an obvious click!!
The circuit goes:
Battery positive
Power relay
Injector series resistors
Injector
Ecu ( low side open collector driver)
Ground.
Hence without injectors on, you should see vbatt at each ecu input pin
With injectors on, you'd expect roughly half vbatt across the injector and half across the resistor box ( you'd also expect a small (<1volt) saturation voltage across the ecu driver
As a first check, with KOEO, use a paper clip carefully inserted from rear of ecu plug to short each injector wire to ground. This should energise each injector with an obvious click!!
Are the injector terminals at the ECU opened up and not making a good contact
Dont bother shoving anything up the back of the ECU plug, its the contact point to the ECU pins that your interested in, there could even be broken terminals in the plug and whats happening at the back could fool you. As a 85 year old prostitute once said to me " I look ok at the back dont I"
Dont bother shoving anything up the back of the ECU plug, its the contact point to the ECU pins that your interested in, there could even be broken terminals in the plug and whats happening at the back could fool you. As a 85 year old prostitute once said to me " I look ok at the back dont I"
Penelope Stopit said:
Are the injector terminals at the ECU opened up and not making a good contact
Dont bother shoving anything up the back of the ECU plug, its the contact point to the ECU pins that your interested in, there could even be broken terminals in the plug and whats happening at the back could fool you. As a 85 year old prostitute once said to me " I look ok at the back dont I"
LOLDont bother shoving anything up the back of the ECU plug, its the contact point to the ECU pins that your interested in, there could even be broken terminals in the plug and whats happening at the back could fool you. As a 85 year old prostitute once said to me " I look ok at the back dont I"
I think I've solved it, Almost positive its the camshaft sensor, when its off all four injectors fire, engine fires up on 4 but obviously rough then cuts out.
cheers
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