If you unplug that coil -ve feed to the ECU, then it is definitely running on petrol, as cutting that wire stops the injectors firing.
Chris.
HELP ! >>please
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can there really be that much pressure left in the rail ?
but then saying that i have had it running with both the petrol lines removed and the one to the cold start injector has no fuel in it when it's running
it runs for ages , it had it up to fans on temp today with no fuel connected
but then saying that i have had it running with both the petrol lines removed and the one to the cold start injector has no fuel in it when it's running
it runs for ages , it had it up to fans on temp today with no fuel connected
remember it's only a bodge if it DOSN'T worK
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ramon alban
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Hello Keith - some observations in RED.
You may think you have disconnected the fuel supply or disabled the pump but clearly not so.
The return line from regulator to fuel tank is still connected to the tank and/or the feed line from the pump.
The engine is running on because it is SUCKING up the fuel by the normal depression seen at the intake manifold at idle speed and sufficient fuel comes to the fuel rail by suction, to keep the engine ticking over through the normal function of the injectors.
But in reality its all a mirage, because no-one expects to see a situation where you try to stop the engine by removing a fuel feed or disabling the pump or removing a relay, whatever.
The normal way to stop an engine is by switching it OFF.
Anything else is an abnormal situation and virtually anything might happen as a result.
(It reminds me of situations when folks report that an engine continues to run/function with the AFM or some other key component disconnected, then agonise themselves asking Why?. So What? Its irrelevant because it was not designed that way.)
Go back to basics. put the whole thing back together, Get some appropriate reading material, study it to understand how Efi works, test the components, wiring and air leaks as suggested and resist trying oddball disconnections then trying to figure out why something strange happens.
ODDBALL begets STRANGE.
Keep the faith.
HOWEVER UNLIKELY, HERE IS THE ANSWER YOU CRAVE!.bodger wrote:having cleaned out the plenum and put it all back together , it still did it .. is it possible to have dirt in the injectors holding them open ?
sure, its possible but pretty unlikely without the engine flooding itself to a virtual stop so would think it is irrelevant.
i ran it up to temp with the breather hose still connected to the flame trap but off the other end , quite a lot of mist , but it's really only water certainly not a huge amount of oil there if any ,
Well, remember that a quick look for misting oil is not the same as longer periods of running and yes there is oil in that mist, trust me. Thats why they put an oil trap in the breather system. Check out the things I suggested, filter and baffle.
is there any other way oil could get up into the plenum??
In a word, No! But on the other hand one might speculate that transmission fluid could be sucked up the vacuum line from the transmission modulator valve AND brake fluid could be sucked up from the brake servo.
i did try something else too even though there are no pipes supplying fuel gas or petrol when i unplug the sense wire from the NEG coil to ECU , it stops running !
Well clearly there is fuel in the system and when you disconnect the wire from the coil negative to the ECU that stops the injectors from firing and the engine stops.
and as that has nothing to do with the ignition system so thats not why it stops
As explained, its not the ignition being disconnected that stopped the engine its the removal of the engine running signal from the ECU.
welcome to the mad , tearing my hair out problem
more ideas welcome please
You may think you have disconnected the fuel supply or disabled the pump but clearly not so.
The return line from regulator to fuel tank is still connected to the tank and/or the feed line from the pump.
The engine is running on because it is SUCKING up the fuel by the normal depression seen at the intake manifold at idle speed and sufficient fuel comes to the fuel rail by suction, to keep the engine ticking over through the normal function of the injectors.
But in reality its all a mirage, because no-one expects to see a situation where you try to stop the engine by removing a fuel feed or disabling the pump or removing a relay, whatever.
The normal way to stop an engine is by switching it OFF.
Anything else is an abnormal situation and virtually anything might happen as a result.
(It reminds me of situations when folks report that an engine continues to run/function with the AFM or some other key component disconnected, then agonise themselves asking Why?. So What? Its irrelevant because it was not designed that way.)
Go back to basics. put the whole thing back together, Get some appropriate reading material, study it to understand how Efi works, test the components, wiring and air leaks as suggested and resist trying oddball disconnections then trying to figure out why something strange happens.
ODDBALL begets STRANGE.
Keep the faith.
ramon alban wrote:Hello Keith - some observations in RED.
HOWEVER UNLIKELY, HERE IS THE ANSWER YOU CRAVE!.bodger wrote:having cleaned out the plenum and put it all back together , it still did it .. is it possible to have dirt in the injectors holding them open ?
sure, its possible but pretty unlikely without the engine flooding itself to a virtual stop so would think it is irrelevant.
good point
i ran it up to temp with the breather hose still connected to the flame trap but off the other end , quite a lot of mist , but it's really only water certainly not a huge amount of oil there if any ,
Well, remember that a quick look for misting oil is not the same as longer periods of running and yes there is oil in that mist, trust me. Thats why they put an oil trap in the breather system. Check out the things I suggested, filter and baffle.
there was no oil just a water mist coming from the breather , the baffle is in place and the flame trap filter is clean , i also did a gas in coolant test ( blue liquid)
is there any other way oil could get up into the plenum??
In a word, No! But on the other hand one might speculate that transmission fluid could be sucked up the vacuum line from the transmission modulator valve AND brake fluid could be sucked up from the brake servo.
I have a LT77 manual box , so no link to the engine with the oil , but i have recently added a nonreturn valve in the brake servo line , so i will check that tomorrow to see if the brake fluid has gone down , just in case , but then saying that the engine oil level has gone down a bit latley , but then that still dosn't explain why it stops when the ECU is disconnected
i did try something else too even though there are no pipes supplying fuel gas or petrol when i unplug the sense wire from the NEG coil to ECU , it stops running !
Well clearly there is fuel in the system and when you disconnect the wire from the coil negative to the ECU that stops the injectors from firing and the engine stops.
and as that has nothing to do with the ignition system so thats not why it stops
As explained, its not the ignition being disconnected that stopped the engine its the removal of the engine running signal from the ECU.
welcome to the mad , tearing my hair out problem
more ideas welcome please
You may think you have disconnected the fuel supply or disabled the pump but clearly not so.
The return line from regulator to fuel tank is still connected to the tank and/or the feed line from the pump.
after unplugging the fuel pump i disconnected both feed and return pipes to the fuel rail and it still ran for ages and i could rev it happily and when reconnecting the pipes and powering up the pump again it started to run unevenly again
The engine is running on because it is SUCKING up the fuel by the normal depression seen at the intake manifold at idle speed and sufficient fuel comes to the fuel rail by suction, to keep the engine ticking over through the normal function of the injectors.
But in reality its all a mirage, because no-one expects to see a situation where you try to stop the engine by removing a fuel feed or disabling the pump or removing a relay, whatever.
The normal way to stop an engine is by switching it OFF.
there are 2 real problems , 1 = that fact that when it's all connected as it should be ie: ECU powered up / AFM connected and FUEL pump running , it won't tick over and runs really rough , and the other 2= i'm concerned that when i'm running LPG it is also running on somthing else too
hope thsi makes sense
Anything else is an abnormal situation and virtually anything might happen as a result.
(It reminds me of situations when folks report that an engine continues to run/function with the AFM or some other key component disconnected, then agonise themselves asking Why?. So What? Its irrelevant because it was not designed that way.)
Go back to basics. put the whole thing back together, Get some appropriate reading material, study it to understand how Efi works, test the components, wiring and air leaks as suggested and resist trying oddball disconnections then trying to figure out why something strange happens.
i have done all the tests for the injection system , voltage / resistance etc
ODDBALL begets STRANGE. [/color]
Keep the faith.
remember it's only a bodge if it DOSN'T worK
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ramon alban
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Hello Keith, I cant help feeling that we are really going round in circles and at some point in time you have to put some trust some of the advice.
If you are trying to solve both LPG and Petrol problems at the same time, then what chance is there of making progress with probable overlapping symptoms coming from different sets of supply components.
If you want to move forwards, I suggest you completely disconnect the LPG supply and its relevant components forget about it and and concentrate on getting the system running on petrol only.
At least that is where the majority of expertise is, on the forum, and I would imagine trying to solve both fuel supply situations at the same time is practically impossible.
As for moving forwards, I can only repeat:
"Go back to basics. put the whole thing back together, Get some appropriate reading material, study it to understand how Efi works, test the components, wiring and air leaks as suggested and resist trying oddball disconnections then trying to figure out why something strange happens."
OK, so you dont detect oil in the foul air coming from the crankcase at tickover or in the workshop, so the oil in the plenum chamber remains a mystery, but what if you were to put a catch bottle on the breather and drive the car for a few hundred miles?? I give in!bodger wrote:there was no oil just a water mist coming from the breather , the baffle is in place and the flame trap filter is clean , i also did a gas in coolant test ( blue liquid)
I would say that is a positive situation because at least it is running which means that you can repeat the various tests (wiring/connectivity, air leaks and components) I recommended and see what you might have missed last time around.bodger wrote:when it's all connected as it should be ie: ECU powered up / AFM connected and FUEL pump running , it won't tick over and runs really rough
No it doesn't! To me this is pure nonsense! I was trained and spent a large part of my working life designing and solving electronic test system problems and my personal key to success was always "divide and conquer".bodger wrote:I'm concerned that when I'm running LPG it is also running on somthing else too - hope this makes sense
If you are trying to solve both LPG and Petrol problems at the same time, then what chance is there of making progress with probable overlapping symptoms coming from different sets of supply components.
If you want to move forwards, I suggest you completely disconnect the LPG supply and its relevant components forget about it and and concentrate on getting the system running on petrol only.
At least that is where the majority of expertise is, on the forum, and I would imagine trying to solve both fuel supply situations at the same time is practically impossible.
As for moving forwards, I can only repeat:
"Go back to basics. put the whole thing back together, Get some appropriate reading material, study it to understand how Efi works, test the components, wiring and air leaks as suggested and resist trying oddball disconnections then trying to figure out why something strange happens."
right i have completly stripped and rebuilt it and ran all the tests in the wedge Episle listings ..
and what i have discovered is the afm is knackered , i have had the breather pipe disconnected and feeding into a bottle for about 60 miles thsi afternoon quite a lot of it on a motorway at around 3 to 4 k revs and no real sign of oil , wel nothing like what was in plenum ..
the part about runninmg on both is quite simple really , if it runs fine with NO petrol and NO lpg connected when i'm driving it around on lpg it surely must be running on something else too ...it runs fine on LPG as a matter of fact , and it's not a complicated lpg set up just a vaporsier and mixer with a change over switch so that dosn't get involved with the petrol ECU , apart from the fact that when lpg switches on it cuts the black/white wire to the ECU from the neg coil terminal thus turning off the injectors
i have read you pages about the v8 , i have had them for a while now and didn't realise they were by you ..
oh by the way no loss of brake fluid , so that's not getting sucked in via the servo pipe
and what i have discovered is the afm is knackered , i have had the breather pipe disconnected and feeding into a bottle for about 60 miles thsi afternoon quite a lot of it on a motorway at around 3 to 4 k revs and no real sign of oil , wel nothing like what was in plenum ..
the part about runninmg on both is quite simple really , if it runs fine with NO petrol and NO lpg connected when i'm driving it around on lpg it surely must be running on something else too ...it runs fine on LPG as a matter of fact , and it's not a complicated lpg set up just a vaporsier and mixer with a change over switch so that dosn't get involved with the petrol ECU , apart from the fact that when lpg switches on it cuts the black/white wire to the ECU from the neg coil terminal thus turning off the injectors
i have read you pages about the v8 , i have had them for a while now and didn't realise they were by you ..
oh by the way no loss of brake fluid , so that's not getting sucked in via the servo pipe
remember it's only a bodge if it DOSN'T worK
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ramon alban
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bodger wrote:right i have completly stripped and rebuilt it and ran all the tests in the wedge Episle listings --i have read your pages about the v8, i have had them for a while now and didn't realise they were by you ..
Yeah! All by my own fair hand and keyboard as were the so called Wedge pages a blatent copy of the Operations and Test Manual I compiled for the Rover SD1 Efi community. My source material for that manual was an original Land Rover technician training manual. The thief even took my monica from every page and redigitised it as if it originated with their membership under a false byline.
Check out the intro on the first page.
AS FITTED TO THE 3528cc V8 ENGINE INSTALLED
IN THE ROVER SD1 VITESSE AND EFI VDP
http://www.vintagemodelairplane.com/pag ... ech01.html
Regarding your oil mist thing, remember that under normal conditions the crankcase breather is supplimented by the depression (vacuum) felt at the breather inlet into the plenum chamber, and, like I say, the oil mist condenses out in the plunum chamber.
As for the resolution of your Petrol running problems, I cant really add anything to my prior suggestions except perhaps to study again the excellent material "wot I rote" to gain an ever better understanding of how the whole thing works.
Good luck.
all excellent stuff and very informative ... the tests that have failed are test 3 ..with the AFM connected and shut i'm showing a voltage , but not when it's disconected
test 6 no voltage at all
test 7 no voltage
but test 7 is a bit confusing as it says 6 & 9 twice ?
but 2 of the readings are fine on that one , but everything else including all the injectors are spot on 12.13 volts and 8 ohms across all 8
i wish you where local to me , i'd love to have a natter ... ah bedford , what are doing next weekend ....
..only joking
ps:
the temp sensor = 0.00 ..so i have put a 150ohm resistor in it instead
test 6 no voltage at all
test 7 no voltage
but test 7 is a bit confusing as it says 6 & 9 twice ?
but 2 of the readings are fine on that one , but everything else including all the injectors are spot on 12.13 volts and 8 ohms across all 8
i wish you where local to me , i'd love to have a natter ... ah bedford , what are doing next weekend ....
..only joking ps:
the temp sensor = 0.00 ..so i have put a 150ohm resistor in it instead
remember it's only a bodge if it DOSN'T worK
today i mostly be problem solving !
right clean oil in the plenum again and oil level gone down by about 4mm on the stick
stripped it all down again , cleaned all the injectors .. while i was in there
all plugs look the same , no oiling on any of them ..did a compression test
my gauge isnt that good so ignore the readings as such , just compare one to another
between 97 - 100 DRY ... then 2/3/4/5/6/8 all .. 125 - 127
.. BUT 1=180 ( very wet 250 !!)
and 7=135 ...and thats WET a cap of oil in each one in turn as i did them ..
i had the plenum off at the time so no need to open the throttle
right clean oil in the plenum again and oil level gone down by about 4mm on the stick
stripped it all down again , cleaned all the injectors .. while i was in there
all plugs look the same , no oiling on any of them ..did a compression test
my gauge isnt that good so ignore the readings as such , just compare one to another
between 97 - 100 DRY ... then 2/3/4/5/6/8 all .. 125 - 127
.. BUT 1=180 ( very wet 250 !!)
and 7=135 ...and thats WET a cap of oil in each one in turn as i did them ..
i had the plenum off at the time so no need to open the throttle
remember it's only a bodge if it DOSN'T worK
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ramon alban
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Keith, I know nothing about Engines only Efi, Ign (trying to learn) and Electrics.
Even so, my Workshop Manual says 130psi for late SD1 V8's so No 1 looks weird at 180 to 250.
No! More than weird! Twice the expected compression pressure???
What could make it go that high?
Valves remaining mostly shut??
No Cam Lobes on No 1???
Ouch! That could explain a lot!!!
Ramon
Even so, my Workshop Manual says 130psi for late SD1 V8's so No 1 looks weird at 180 to 250.
No! More than weird! Twice the expected compression pressure???
What could make it go that high?
Valves remaining mostly shut??
No Cam Lobes on No 1???
Ouch! That could explain a lot!!!
Ramon
Thankyou Chris 
i think this might be the problem
bottom centre
i'll update in about 10 mins
would you believe it , it works
somthing as simple as that and takes 5 mins to fix ...aaaggghhhh
all i have done is solder in a piece of telephonewire to bridge the gap and job done
i think this might be the problem
bottom centre
i'll update in about 10 mins
would you believe it , it works
somthing as simple as that and takes 5 mins to fix ...aaaggghhhh
all i have done is solder in a piece of telephonewire to bridge the gap and job done
remember it's only a bodge if it DOSN'T worK
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CastleMGBV8
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