Discussion
The early ECUs have a soldered ROM Chip so you would not be able to plug in your Chim 500 chip.
The later ones have a socket for the ROM so changing the Chip is straightforward.
If you are handy with a soldering iron its not too difficult to update an older ECU and insert a ROM socket but as it is a double sided printed circuit you have to be careful.
Easier to locate a later ECU, someone on here will know the appropriate date code, it escapes me at the moment.
The later ones have a socket for the ROM so changing the Chip is straightforward.
If you are handy with a soldering iron its not too difficult to update an older ECU and insert a ROM socket but as it is a double sided printed circuit you have to be careful.
Easier to locate a later ECU, someone on here will know the appropriate date code, it escapes me at the moment.
My date code of 0595 looks like maybe it is number 5 from 1995, if someone could confirm that this is how to read the date code and at what number and date they changed to removable chips that would be great, I don’t mind swapping chips when there is a socket but don’t really want to swap round soldered ones.
The chip can still be changed but needs some kit to do it. You cut the chip legs so the chip can be removed then de-solder each pin one at a time. You will need to solder suck or solder wick so each hole is clear then solder into place a socket into which you fit your new chip.
However, first you need to test the car on this new ECU and see if that is the issue.
If it cures the problem then it would be best to see if a new chip will cure your existing ECU rather than messing with a soldering iron.
The new chip from Steve Sprint would be a good move whichever ECU you end up using.
Steve
However, first you need to test the car on this new ECU and see if that is the issue.
If it cures the problem then it would be best to see if a new chip will cure your existing ECU rather than messing with a soldering iron.
The new chip from Steve Sprint would be a good move whichever ECU you end up using.
Steve
Hi Steve
I cant really use the new one with the Land rover chip as i guess i cant go for a good thrashing or drive it for a few hours that it normally takes to play up, so i will go for fitting a socket, i have had no luck finding information on how to determine which ecu has a socket or not, a couple of guys have opened them up for me but all are soldered so far, do you know the part number for the socket ??
Paul
I cant really use the new one with the Land rover chip as i guess i cant go for a good thrashing or drive it for a few hours that it normally takes to play up, so i will go for fitting a socket, i have had no luck finding information on how to determine which ecu has a socket or not, a couple of guys have opened them up for me but all are soldered so far, do you know the part number for the socket ??
Paul
Paulprior said:
Ok, but your sure that even if it’s for a 3.9 it will be ok pottering around on my 5.0?
If that works out ok I could refit the original next time I need to give it a thrashing and then Change over when it starts to play up
A 500 would ideally like more fueling but this will only become critical if you are pushing on.If that works out ok I could refit the original next time I need to give it a thrashing and then Change over when it starts to play up
If the problem comes on after a period of time or at temperature a lengthy gentle drive should bring it on. But, as you say, you could leave your own one on until the fault then replace.
Steve
Fox TVR430, would you have the external details on the ECU, is it the same as mine thats pictured higher up the thread ?
Steve D, yes it only happens when hot, especially if the ECU is mounted by the battery annd then enclosed with the carpeted section in front of the battery which closes everything in, generally everything works well if i leave the ECU laying on the floor, so i will fit the new one, mount it beside the battery and close it in and go for a long gentle cruise.
Paul
Steve D, yes it only happens when hot, especially if the ECU is mounted by the battery annd then enclosed with the carpeted section in front of the battery which closes everything in, generally everything works well if i leave the ECU laying on the floor, so i will fit the new one, mount it beside the battery and close it in and go for a long gentle cruise.
Paul
Paulprior said:
Fox TVR430, would you have the external details on the ECU, is it the same as mine that's pictured higher up the thread?
Steve D, yes it only happens when hot, especially if the ECU is mounted by the battery and then enclosed with the carpeted section in front of the battery which closes everything in, generally everything works well if I leave the ECU laying on the floor, so I will fit the new one, mount it beside the battery and close it in and go for a long gentle cruise.
Paul
Hi Paul, happy to oblige. Steve D, yes it only happens when hot, especially if the ECU is mounted by the battery and then enclosed with the carpeted section in front of the battery which closes everything in, generally everything works well if I leave the ECU laying on the floor, so I will fit the new one, mount it beside the battery and close it in and go for a long gentle cruise.
Paul
Photo pf the outside of the ECU.
Simon
P.S. As Steve says above I have also found that in the main ECU cable loom a soldered/crimped connection of Earth (Black) cables that were in really bad condition.
Worth a check I reckon.
I have read somewhere that the ECU's with EPROMs mounted on a socket were introduced after a certain date but cannot locate the source.
Also if my memory is correct that TVR always used sockets as they updated the original EPROMs to fit their own for each engine type.
The problem in 2019 is that many previously hard wired EPROM ECUs will have been updated by owners etc. so that the date code on the ECU case becomes meaningless.
I have personally soldered sockets into two previously early hard wired units so the only true test now is to remove the cover.
As Steve says it is a bit of a fiddly procedure so best tackled if you are familiar with double sided printed circuits.
I think I have some spare EPROM sockets somewhere.
Also if my memory is correct that TVR always used sockets as they updated the original EPROMs to fit their own for each engine type.
The problem in 2019 is that many previously hard wired EPROM ECUs will have been updated by owners etc. so that the date code on the ECU case becomes meaningless.
I have personally soldered sockets into two previously early hard wired units so the only true test now is to remove the cover.
As Steve says it is a bit of a fiddly procedure so best tackled if you are familiar with double sided printed circuits.
I think I have some spare EPROM sockets somewhere.
Thanks for the thoughts and info all
I have considered the cabling and stripped back all the covering as well as the connector cover, everything looks very good, I have also tried moving it around with engine running as well as getting my wife to do the same while driving, but I cannot create the fault this way unfortunately.
I have also read that all 14 cuz had a socket after a date, but I cannot find it either, also that all TVRs had a socket , unfortunately anyone selling a TVR one wants several hundred pounds more, so I will test tonight on the Land Rover system and see what happens, the only problem being how long to test for as the fault can be very random and I have considered twice before that I had fixed it, first time I found that 3 chip pins were bent over rather than inserted into the socket, second time was after bypassing the immobiliser, both times all problems disappeared for a few months before returning, so very frustrating
I have considered the cabling and stripped back all the covering as well as the connector cover, everything looks very good, I have also tried moving it around with engine running as well as getting my wife to do the same while driving, but I cannot create the fault this way unfortunately.
I have also read that all 14 cuz had a socket after a date, but I cannot find it either, also that all TVRs had a socket , unfortunately anyone selling a TVR one wants several hundred pounds more, so I will test tonight on the Land Rover system and see what happens, the only problem being how long to test for as the fault can be very random and I have considered twice before that I had fixed it, first time I found that 3 chip pins were bent over rather than inserted into the socket, second time was after bypassing the immobiliser, both times all problems disappeared for a few months before returning, so very frustrating
spitfire4v8 said:
Steve_D said:
boustrophedonically
I don't have anything to add to the thread, but wanted to say : epic wordsmithery there Steve !!and yes I did have to look it up
Steve
Perhaps I have missed something but all efforts seem to be directed at the ECU and the injectors. Could it not be something rather more basic like a poor connection in one of the many multiway plugs in the immobiliser/fuel-pump/ignition circuits.
I had a similar problem years back so methodically inspected and cleaned all the multiway plugs/sockets and the intermittent fault disappeared never to return. Have a look here:
http://www.bertram-hill.com/fuel-pump-schematic.ht...
And mail me for the immobiliser schematic
I may be completely wrong, but I always remember what a wise old BBC engineer once said to me:
"Always suspect a simple fault because in 9 times out of 10 it usually is"
My experience over 50 years has proved that to be generally correct
I had a similar problem years back so methodically inspected and cleaned all the multiway plugs/sockets and the intermittent fault disappeared never to return. Have a look here:
http://www.bertram-hill.com/fuel-pump-schematic.ht...
And mail me for the immobiliser schematic
I may be completely wrong, but I always remember what a wise old BBC engineer once said to me:
"Always suspect a simple fault because in 9 times out of 10 it usually is"
My experience over 50 years has proved that to be generally correct
Hi Loubaruch
I fully agree that most faults end up being something basic, but this isnt a sudden dive into injectors and ecu, i have been playing with this fault on and off for the last 3 years since i bought the car, during that time i have stripped down the electrics and connectors as far as possible, replaced some components, tried measuring various voltages or connecting LEDs at various points but its so erratic that i have never been able to pin point the issue, or issues, i also intermittently have a complete cut out which cannot be reset just by restarting, it fires up for a few seconds and then cuts out, but a reset of the immobiliser always sorts it out.
But all through the time it has been very evident that it all works much better with the ecu on the floor rather than tucked away somewhere neater, i have also heard from friends following in Caterhams that there is a heavy petrol smell while having the rough running issue, so i thought a quick swap of the ecu was going to be an easy check, if it doesnt fix it then i simply resell it so no real cost involved
I have also spent most of my life in the troubleshooting game and although i dont generally like just swapping parts sometimes with very intermittent problems it is the only way unless you wait for the issue to become full time, at which point its easy to find and correct, but while i might do 1000 miles running perfectly and then the next run its a complete pig, so any possible thoughts of a better route forward are greatly appreciated as apart from these little occasional gremlins the car runs very well.
Paul
I fully agree that most faults end up being something basic, but this isnt a sudden dive into injectors and ecu, i have been playing with this fault on and off for the last 3 years since i bought the car, during that time i have stripped down the electrics and connectors as far as possible, replaced some components, tried measuring various voltages or connecting LEDs at various points but its so erratic that i have never been able to pin point the issue, or issues, i also intermittently have a complete cut out which cannot be reset just by restarting, it fires up for a few seconds and then cuts out, but a reset of the immobiliser always sorts it out.
But all through the time it has been very evident that it all works much better with the ecu on the floor rather than tucked away somewhere neater, i have also heard from friends following in Caterhams that there is a heavy petrol smell while having the rough running issue, so i thought a quick swap of the ecu was going to be an easy check, if it doesnt fix it then i simply resell it so no real cost involved
I have also spent most of my life in the troubleshooting game and although i dont generally like just swapping parts sometimes with very intermittent problems it is the only way unless you wait for the issue to become full time, at which point its easy to find and correct, but while i might do 1000 miles running perfectly and then the next run its a complete pig, so any possible thoughts of a better route forward are greatly appreciated as apart from these little occasional gremlins the car runs very well.
Paul
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