Running problems with Lucas L (flapper 4CU) injection system
Discussion
Thought it a good idea to go back to your very first post (when you reported hunting/idle issues and only an occasional problem when running normally) and review what had happened prior to that date?
1 A competent (??) AE discovered that all the components tested out OK but the ECU multiplug connector was at fault OR the ECU was faulty.
2 You subsequently replaced the AFM which eliminated the original hunting and poor idle problem, but left you with a permament lack of power over 2500 rpm (Yet the AE said all the components/sensors were Working OK)
3 The AE or someone else replaced the ECU multiplug with some spades and when this did not cure the problem you then refitted the ECU multiplug to the loom and replaced the ECU at the same time.
(as the AE diagnosed either or both, the loom and the ECU as being faulty, then carrying out the work mentioned should have fixed the problem but it didn't, hence the rewiring of the loom/multiplug.
Thus, it seems to me the, these three things have to be examined as needing attention
1 Was the rewiring of the ECU multiplug carried out competently and accurately?
2 Was the replacement ECU an actual working unit?
3 Have any of the subsequently recommended electrical component tests been carried out SINCE the ECU multiplug has been rewired?
Despite much prompting and suggested solutions I detect the distinct possibilty that very little if any actual testing of wiring, testing of components and testing for air leaks has actually been undertaken.
As previously mentioned, if there is an endemic fault in either the loom or in the plenum chamber integrity, then no amount of component replacement will resolve the issues.
If you review the component testing instructions that are available to you, you'll note that, without exception, all the tests INCLUDE the loom wiring in the detailed instructions, so, given that the test are actually undertaken as proscribed, then there would also be a very good chance of uncovering a loom wiring/connectivity problem at the same time.
Because Air Leaks are such a common cause of Efi system problems, I urge you again, to carry out the dynamic tests as proscribed, paricularly as the test process does require the engine to be capable of idling, which, luckily your engine is so endowed, for the time being, at least.
s1v8esprit said:
TVR (wedge 350i) - not running very well, does not tickover (hunting and stalling) does not rev very well did not like going over 2500rpm most of the time
sometimes would rev ok
had an auto electrician test it and all sensors are working, diagnosed as faulty ecu plug or ecu
ecu plug has been cut off and spade ends fitted, was told this fixed the problem, however it has not fixed the problem, still the same!
I have now replaced the ecu plug wiring and changed the ecu (been told these were working) ..... no difference!!!
Bearing in mind the subsequent forum discussions, suggestions and your responses, and the host of parts you have also replaced without success, one is now drawn to the inevitable conclusion that the work carried out prior to your first post has to be called into question as the actual cause of the problems currently being encountered.sometimes would rev ok
had an auto electrician test it and all sensors are working, diagnosed as faulty ecu plug or ecu
ecu plug has been cut off and spade ends fitted, was told this fixed the problem, however it has not fixed the problem, still the same!
I have now replaced the ecu plug wiring and changed the ecu (been told these were working) ..... no difference!!!
1 A competent (??) AE discovered that all the components tested out OK but the ECU multiplug connector was at fault OR the ECU was faulty.
2 You subsequently replaced the AFM which eliminated the original hunting and poor idle problem, but left you with a permament lack of power over 2500 rpm (Yet the AE said all the components/sensors were Working OK)
3 The AE or someone else replaced the ECU multiplug with some spades and when this did not cure the problem you then refitted the ECU multiplug to the loom and replaced the ECU at the same time.
(as the AE diagnosed either or both, the loom and the ECU as being faulty, then carrying out the work mentioned should have fixed the problem but it didn't, hence the rewiring of the loom/multiplug.
Thus, it seems to me the, these three things have to be examined as needing attention
1 Was the rewiring of the ECU multiplug carried out competently and accurately?
2 Was the replacement ECU an actual working unit?
3 Have any of the subsequently recommended electrical component tests been carried out SINCE the ECU multiplug has been rewired?
Despite much prompting and suggested solutions I detect the distinct possibilty that very little if any actual testing of wiring, testing of components and testing for air leaks has actually been undertaken.
As previously mentioned, if there is an endemic fault in either the loom or in the plenum chamber integrity, then no amount of component replacement will resolve the issues.
If you review the component testing instructions that are available to you, you'll note that, without exception, all the tests INCLUDE the loom wiring in the detailed instructions, so, given that the test are actually undertaken as proscribed, then there would also be a very good chance of uncovering a loom wiring/connectivity problem at the same time.
Because Air Leaks are such a common cause of Efi system problems, I urge you again, to carry out the dynamic tests as proscribed, paricularly as the test process does require the engine to be capable of idling, which, luckily your engine is so endowed, for the time being, at least.
Edited by honestjohntoo on Saturday 18th December 23:16
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