LH computer (fuel injection brain) rebuild
#1
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I went to start my car one day, and as soon as the ignition key was turned to the on position, I heard the dreaded steadily clicking injector sound. At that point I didn't even try to start the car, since I already knew what that sound meant. A dead LH computer.
There's never a good time for LH computer failure, but I can't really complain too much. Since my car still had it's original LH computer, I pretty much knew I was on borrowed time, and had been kind of expecting this to happen one day. Fortunately this occurred when the car was parked in the garage, and not late on a cold rainy night in the middle of nowhere.
I took the LH computer along when going over to another 928 owner's house, just to verify that it was dead by testing it in his car. Plugging it into his car resulted in the same clicking of the injectors with the ignition switched on, and in a failure to start. Diagnosis confirmed.
I then sent the LH computer off to John Speake at www.jdsporsche.com. Upon receiving it, he tested it and notified me that it was absolutely, positively dead, and that he would be able to rebuild it. I didn't really have any need to get a functioning LH computer in any particular hurry, so I told John that there was no rush, and that he could feel free to take his time if he needed or wanted to. I was kind of surprised when the LH computer was back in my hands faster than I was really expecting.
When I plugged it back into my car and turned on the ignition, there was none of the injector clicking anymore. I turned the key to engage the starter and the car immediately started. It started before the fuel pressure was even completely up all the way, and idled perfectly smoothly, without the computer even having to do any noticeable "relearning" to achieve a smooth idle.
Thanks from a satisfied customer John.
There's never a good time for LH computer failure, but I can't really complain too much. Since my car still had it's original LH computer, I pretty much knew I was on borrowed time, and had been kind of expecting this to happen one day. Fortunately this occurred when the car was parked in the garage, and not late on a cold rainy night in the middle of nowhere.
I took the LH computer along when going over to another 928 owner's house, just to verify that it was dead by testing it in his car. Plugging it into his car resulted in the same clicking of the injectors with the ignition switched on, and in a failure to start. Diagnosis confirmed.
I then sent the LH computer off to John Speake at www.jdsporsche.com. Upon receiving it, he tested it and notified me that it was absolutely, positively dead, and that he would be able to rebuild it. I didn't really have any need to get a functioning LH computer in any particular hurry, so I told John that there was no rush, and that he could feel free to take his time if he needed or wanted to. I was kind of surprised when the LH computer was back in my hands faster than I was really expecting.
When I plugged it back into my car and turned on the ignition, there was none of the injector clicking anymore. I turned the key to engage the starter and the car immediately started. It started before the fuel pressure was even completely up all the way, and idled perfectly smoothly, without the computer even having to do any noticeable "relearning" to achieve a smooth idle.
Thanks from a satisfied customer John.
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#3
Drifting
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My LH died during the first week of a three week touring holiday in Europe, at the time I hadn't heard of John or an LH ECU for that matter, and when it was diagnosed I had it replaced with a used unit. Needless to say I am waiting for the inevitable day when the replacement fails. I just hope its not when I'm on holiday in Europe again next month...
#6
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Herr Kuhn, A plug in replacement isn't as easy at it sounds ! The LH 2.3 has an Achilles heel, otherwise it's a relaible as the older L jet ECUs. It's cheaper and easier to get an existing LH ECU rebuild than any alternative.
Paul, I'm sorry to say you are on borrowed time... :-)
Schocki - cheers ! I'm pleased today because my S2 passed it's annual inspection yesterday ...!
Paul, I'm sorry to say you are on borrowed time... :-)
Schocki - cheers ! I'm pleased today because my S2 passed it's annual inspection yesterday ...!
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#8
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"Someone should come up with a plug in replacement for that computer. I guess the L-Jet brains are pretty bullet-proof....guess I'll not need that spare." - Herr-Huhn -
The 928 LH control unit is a very reliable ECU, once the failure-prone hybrid part is replaced.
The condition which accelerates the failure is overvoltaging the electrical system
when using a high capacity battery charger (or starting charger). When a battery
is very low, most chargers will provide a high voltage, i.e. > 15 volts, causing damage
to the LH unit and other ECUs in the system.
Many Rennlist sponsors these days provide updated LH control units at very competitive prices.
The 928 LH control unit is a very reliable ECU, once the failure-prone hybrid part is replaced.
The condition which accelerates the failure is overvoltaging the electrical system
when using a high capacity battery charger (or starting charger). When a battery
is very low, most chargers will provide a high voltage, i.e. > 15 volts, causing damage
to the LH unit and other ECUs in the system.
Many Rennlist sponsors these days provide updated LH control units at very competitive prices.
#12
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Originally Posted by jyoon
anyone know anyone in the us that repairs these? or is it no big deal to send to the UK? how much is shippng? thanks.
Rich