Electrical nightmare, I need help
01-16-2006, 04:56 PM
#31
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Typically they fire up rather quickly...I usually have someone send me their brain BEFORE I send them one just to confirm that their brain is really bad ! plus we test our LH brains BEFORE we ship them.
01-16-2006, 10:45 PM
#32
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Does the fuel rail have a schrader valve to test the fuel pressure when the fuel pump is jumpered? Then at least you'll know if your getting pressure to the injectors. Like you said, the car runs with the spraying fuel into the intake.
I think the guys had valid points about connectors, de-ox-it, and crank sensors. The fuel delivery could be affected by a few other things like fuel pressure, injector pulses and ECU operation input from crank sensors.
Power washing on a 20 year old car is a big no-no unless your looking for problems to happen. Your best bet is to carefully clean with a non high pressure source and stay away from electrical stuff altogether, clean them with a spray bottle and a clean rag if you absolutely must. I used to clean with a pressure washer and got away with it, but it finally caught up with me and I had a few electrical issues to deal with.
I think the guys had valid points about connectors, de-ox-it, and crank sensors. The fuel delivery could be affected by a few other things like fuel pressure, injector pulses and ECU operation input from crank sensors.
Power washing on a 20 year old car is a big no-no unless your looking for problems to happen. Your best bet is to carefully clean with a non high pressure source and stay away from electrical stuff altogether, clean them with a spray bottle and a clean rag if you absolutely must. I used to clean with a pressure washer and got away with it, but it finally caught up with me and I had a few electrical issues to deal with.
01-16-2006, 11:35 PM
#33
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Sounds like a dead LH to me. I helped a fellow lister with a no-start and we found that his LH had failed in such a way that it was absolutely flooding the cylinders with gasoline. We had to put new plugs in his engine in order for it to start with my LH, the ones that fouled were brand new! Dave, it is a possibility that this is why you had trouble starting your engine again after trying out his LH.
01-17-2006, 12:37 AM
#34
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Originally Posted by Bill Swift
Sounds like a dead LH to me. I helped a fellow lister with a no-start and we found that his LH had failed in such a way that it was absolutely flooding the cylinders with gasoline. We had to put new plugs in his engine in order for it to start with my LH, the ones that fouled were brand new! Dave, it is a possibility that this is why you had trouble starting your engine again after trying out his LH.
01-17-2006, 12:42 AM
#35
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Matt,
Both brains, the LH and the Ignition brains in question were in working condition (non defective) and have been tested just prior to you taking possesion of them. The brains did start and a 928 did run correctly with them. This is fact.
The set of brains in question that you received 'did not' have aftermarket chips installed by the PO, the chips in the brains were OEM Porsche chips.
Informed today by a reliable source that both brains need the same set of matched chips (lost translation and or wording, maybe stated as same BIOS?) for the brains to work as engineered.
If Big Dave switched out his "chipped" LH brain with your "non chipped" LH brain, and his 928 did not start that would make sense. This would make Big Dave's diagnoises of a defective LH brain incorrect. Since your LH, and Ignition brains had normal OEM chips.
Jim B., Wally P, DR, John Speakes, or Rich:
If what is posted in this post is incorrect please chime in. Secondly, please chime in again if Big Dave's diagnoises of Matt's LH brain in question is incorrect, now given all the pertinent information about the brains and their chips.
Matt,
If you switched both brains you received into another shark, the shark would fire-up and run.
Maybe Rich or John Speakes or other Rennlister's can chime in on how to correctly diagnois your non running shark problem, or send you the tech books on how to correctly diagnois your 928 no start problem.
Not sure if a battery that is defective, or not holding a charge could be the culprit of Your non running 928? That or charging a battery in a 928 without disconnecting the battery negative cable could cause problems with a brain?
When you received the brains, Ken told me that your shark stopped running after the engine being power washed? Is this correct?
Both brains, the LH and the Ignition brains in question were in working condition (non defective) and have been tested just prior to you taking possesion of them. The brains did start and a 928 did run correctly with them. This is fact.
The set of brains in question that you received 'did not' have aftermarket chips installed by the PO, the chips in the brains were OEM Porsche chips.
Informed today by a reliable source that both brains need the same set of matched chips (lost translation and or wording, maybe stated as same BIOS?) for the brains to work as engineered.
If Big Dave switched out his "chipped" LH brain with your "non chipped" LH brain, and his 928 did not start that would make sense. This would make Big Dave's diagnoises of a defective LH brain incorrect. Since your LH, and Ignition brains had normal OEM chips.
Jim B., Wally P, DR, John Speakes, or Rich:
If what is posted in this post is incorrect please chime in. Secondly, please chime in again if Big Dave's diagnoises of Matt's LH brain in question is incorrect, now given all the pertinent information about the brains and their chips.
Matt,
If you switched both brains you received into another shark, the shark would fire-up and run.
Maybe Rich or John Speakes or other Rennlister's can chime in on how to correctly diagnois your non running shark problem, or send you the tech books on how to correctly diagnois your 928 no start problem.
Not sure if a battery that is defective, or not holding a charge could be the culprit of Your non running 928? That or charging a battery in a 928 without disconnecting the battery negative cable could cause problems with a brain?
When you received the brains, Ken told me that your shark stopped running after the engine being power washed? Is this correct?
Last edited by Dozman; 01-21-2006 at 07:40 PM.
01-17-2006, 01:50 AM
#36
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Originally Posted by Dozman
Matt,
Both brains, the LH and the Ignition brains in question were in working condition (non defective) and have been tested just prior to you taking possesion of them. The brains did start and a 928 did run correctly with them. This is fact.
The set of brains in question that you received 'did not' have aftermarket chips installed by the PO, the chips in the brains were OEM Porsche chips.
Informed today by a reliable source that both brains need the same set of matched chips (lost translation and or wording, maybe stated as same BIOS?) for the brains to work as engineered.
If Big Dave switched out his "chipped" LH brain with your "non chipped" LH brain, and his 928 did not start that would make sense. This would make Big Dave's diagnoises of a defective LH brain incorrect. Since your LH, and Ignition brains had normal OEM chips.
Jim B., Wally P, DR, John Speakes, or Rich:
If what is posted in this post is incorrect please chim in. Secondly, please chim in again if Big Dave's diagnoises of Matt's defective LH brain in question is incorrect, now given all the pertinent information about the brains and their chips.
Matt,
If you switched both brains you received into another shark, the shark would fire-up and run.
Maybe Rich or John Speakes or other Rennlister's can chim in on how to correctly diagnois your non running shark problem, or send you the tech books on how to correctly diagnois your 928 no start problem.
Not sure if a battery that is defective, or not holding a charge could be the culprit of Your non running 928? That or charging a battery in a 928 without disconnecting the battery negative cable could cause problems with a brain?
When you received the brains, Ken told me that your shark stopped running after the engine being power washed? Is this correct?
Both brains, the LH and the Ignition brains in question were in working condition (non defective) and have been tested just prior to you taking possesion of them. The brains did start and a 928 did run correctly with them. This is fact.
The set of brains in question that you received 'did not' have aftermarket chips installed by the PO, the chips in the brains were OEM Porsche chips.
Informed today by a reliable source that both brains need the same set of matched chips (lost translation and or wording, maybe stated as same BIOS?) for the brains to work as engineered.
If Big Dave switched out his "chipped" LH brain with your "non chipped" LH brain, and his 928 did not start that would make sense. This would make Big Dave's diagnoises of a defective LH brain incorrect. Since your LH, and Ignition brains had normal OEM chips.
Jim B., Wally P, DR, John Speakes, or Rich:
If what is posted in this post is incorrect please chim in. Secondly, please chim in again if Big Dave's diagnoises of Matt's defective LH brain in question is incorrect, now given all the pertinent information about the brains and their chips.
Matt,
If you switched both brains you received into another shark, the shark would fire-up and run.
Maybe Rich or John Speakes or other Rennlister's can chim in on how to correctly diagnois your non running shark problem, or send you the tech books on how to correctly diagnois your 928 no start problem.
Not sure if a battery that is defective, or not holding a charge could be the culprit of Your non running 928? That or charging a battery in a 928 without disconnecting the battery negative cable could cause problems with a brain?
When you received the brains, Ken told me that your shark stopped running after the engine being power washed? Is this correct?
For an '86 US Spec 928, the EPROM should have this number: 2 287 355 590 (may not be spaces between groups of 3 numbers).
The relay swap for '85 to '86 is different than for S4s and later 928s! Just to be sure, swap these relays.
Relay/ Function/ part number
XVI EZF Ignition System 141.951.253.B
XX Fuel Pump,O2 Sensor 141.951.253.B
XXV LH- Fuel Injection 141.951.253.B
XII Horns 141.951.253.B
Also, be sure to check that the proper relay is in the kick-down socket XV. I've heard that the wrong relay in this socket will result in a no-start condition.
XV Kick-Down Relay(Auto) thru 86 VIN#0998 Relay 928.618.109.00
XV Kick-Down Relay(Auto) 86 VIN# 09999 and higher Relay 928.618.109.01
The LH fuel injection controler generation used in 85 - 86 928s doesn't have the hybrid circuit so those failures don't occur. For the most part, these LHs are very robust and don't fail nearly as often as those used in S4 and newer 928s.
You should verify that power and ground are provided to both LH (Jumpered relay socket to connector pin 9, ground to connector pins 11 and 25, ignition switch "on" battery voltage to connector 18) and EZF (battery voltage from jumpered EZF relay socket to EZF connector pin 25, ground at EZF connector pin 12). You also need to verify that the circuit between EZF and LH is good (LH connector pin 1 to EZF connector pin 16).
Lastly, I don't see any mention in the thread that you've verified that you have spark. The EZF unit provides the engine RPM signals to the LH, so if there is something wrong with the EZF or engine crank position sensor, there will be no fuel injection.
Hope this info helps.
01-17-2006, 05:06 AM
#37
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When a running 928 that has aftermarket chips installed in the LH and EZF brains were to have only the LH brain with the after market chip replaced with an LH brain with an OEM chip, the 928 would not start. Thus the LH brain with the OEM chip would appear as if it were defective. As in the same situation when Big Dave attempted to try and diagnois if Matt's LH brain was defective or not.
When Big Dave reinstalled his LH brain equipped with an aftermarket chip back into his 928, the 928 started again. Here is where the miss diagnoises of the LH brain being supposedly defective came from.
Big Dave try and replace both of Matt's brains he rec'd, the 928 would start.
When Big Dave reinstalled his LH brain equipped with an aftermarket chip back into his 928, the 928 started again. Here is where the miss diagnoises of the LH brain being supposedly defective came from.
Big Dave try and replace both of Matt's brains he rec'd, the 928 would start.
Last edited by Dozman; 01-21-2006 at 07:43 PM.
01-17-2006, 05:21 AM
#38
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As Rich suggested, try pinning out the ecu's to determine the no start problem on your 928, esp. the crank sensor.
Maybe Rich or another Rennlister can send you some info for you and Big Dave to pin out each conductor on the ecu connector's to determine your 928 no start cause.
Originally Posted by Rich9928p
I tested the injectors with a noid light I have pressure to the injectors but I have no signal Did you check the voltage on the fuel injectors when the relay positions were all jumpered? There should be 12V at the fuel injectors when the ignition is turned on or relays jumpered. The LH fuel injection controller provides the ground switch, so if there is no switching when the engine cranks the LH isn't working - or it isn't getting the engine rotation information from the EZK spark controller (check the circuit EZK pin 13 to LH pin 1).
01-21-2006, 11:59 AM
#40
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Hey Dave
... He has the money and from what I see he sent a good LH. I don't see him shirking responsibiity just yet, I see him saying, you eed to test with both chips stock or both chips aftermarket. How long is the warrantee on an LH from the Big 3? How long has Matt had this one>
... He has the money and from what I see he sent a good LH. I don't see him shirking responsibiity just yet, I see him saying, you eed to test with both chips stock or both chips aftermarket. How long is the warrantee on an LH from the Big 3? How long has Matt had this one>
01-21-2006, 02:32 PM
#41
Burning Brakes
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Originally Posted by Rich9928p
The LH and EZF use different EPROM chips and must be inserted in the proper orientation (pin 1 in the proper corner). I've had customers that got things mixed up when changing chips around.
For an '86 US Spec 928, the EPROM should have this number: 2 287 355 590 (may not be spaces between groups of 3 numbers).
The relay swap for '85 to '86 is different than for S4s and later 928s! Just to be sure, swap these relays.
Relay/ Function/ part number
XVI EZF Ignition System 141.951.253.B
XX Fuel Pump,O2 Sensor 141.951.253.B
XXV LH- Fuel Injection 141.951.253.B
XII Horns 141.951.253.B
Also, be sure to check that the proper relay is in the kick-down socket XV. I've heard that the wrong relay in this socket will result in a no-start condition.
XV Kick-Down Relay(Auto) thru 86 VIN#0998 Relay 928.618.109.00
XV Kick-Down Relay(Auto) 86 VIN# 09999 and higher Relay 928.618.109.01
The LH fuel injection controler generation used in 85 - 86 928s doesn't have the hybrid circuit so those failures don't occur. For the most part, these LHs are very robust and don't fail nearly as often as those used in S4 and newer 928s.
You should verify that power and ground are provided to both LH (Jumpered relay socket to connector pin 9, ground to connector pins 11 and 25, ignition switch "on" battery voltage to connector 18) and EZF (battery voltage from jumpered EZF relay socket to EZF connector pin 25, ground at EZF connector pin 12). You also need to verify that the circuit between EZF and LH is good (LH connector pin 1 to EZF connector pin 16).
Lastly, I don't see any mention in the thread that you've verified that you have spark. The EZF unit provides the engine RPM signals to the LH, so if there is something wrong with the EZF or engine crank position sensor, there will be no fuel injection.
Hope this info helps.
For an '86 US Spec 928, the EPROM should have this number: 2 287 355 590 (may not be spaces between groups of 3 numbers).
The relay swap for '85 to '86 is different than for S4s and later 928s! Just to be sure, swap these relays.
Relay/ Function/ part number
XVI EZF Ignition System 141.951.253.B
XX Fuel Pump,O2 Sensor 141.951.253.B
XXV LH- Fuel Injection 141.951.253.B
XII Horns 141.951.253.B
Also, be sure to check that the proper relay is in the kick-down socket XV. I've heard that the wrong relay in this socket will result in a no-start condition.
XV Kick-Down Relay(Auto) thru 86 VIN#0998 Relay 928.618.109.00
XV Kick-Down Relay(Auto) 86 VIN# 09999 and higher Relay 928.618.109.01
The LH fuel injection controler generation used in 85 - 86 928s doesn't have the hybrid circuit so those failures don't occur. For the most part, these LHs are very robust and don't fail nearly as often as those used in S4 and newer 928s.
You should verify that power and ground are provided to both LH (Jumpered relay socket to connector pin 9, ground to connector pins 11 and 25, ignition switch "on" battery voltage to connector 18) and EZF (battery voltage from jumpered EZF relay socket to EZF connector pin 25, ground at EZF connector pin 12). You also need to verify that the circuit between EZF and LH is good (LH connector pin 1 to EZF connector pin 16).
Lastly, I don't see any mention in the thread that you've verified that you have spark. The EZF unit provides the engine RPM signals to the LH, so if there is something wrong with the EZF or engine crank position sensor, there will be no fuel injection.
Hope this info helps.
01-21-2006, 03:18 PM
#42
928 Engine Re-Re-Rebuild Specialist
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Originally Posted by heinrich
Hey Dave ... He has the money and from what I see he sent a good LH. I don't see him shirking responsibiity just yet, I see him saying, you eed to test with both chips stock or both chips aftermarket. How long is the warrantee on an LH from the Big 3? How long has Matt had this one>
... He has the money and from what I see he sent a good LH. I don't see him shirking responsibiity just yet, I see him saying, you eed to test with both chips stock or both chips aftermarket. How long is the warrantee on an LH from the Big 3? How long has Matt had this one>
01-29-2006, 02:29 PM
#43
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Hello All, I am sorry to say my car si still not running.
this is where I am at and what Know.
I have all new relays and they are the correct part numbers.
All contacts from the relays to there specific destinations are all good, no broken wire or connections.
I am getting power to the fuel injectors , but no ground. the ground come from the LH pin 13.
the male female connector on the crank sensor was broken, I don't know if the part was actually bad.
I have replaced the crank sensor with a brand new one from 928 specialists
118.00 did not help, I checked the connection from the sensor to the EZF
and the connections is fine.
I took the fuel pump relay and the LA relay out and jumpered them, It did not help.
the fuel pump only runs if the relay is jumpered or I run a straight hot line to the pump.
with the pump jumpered I have pressure and spark to the plugs, the injector are not getting a signal !!!
Can anyone tell me why?
If you read previous post dozman is telling me this LH unit is fine.
My crank sensor is new.
please help thank you
this is where I am at and what Know.
I have all new relays and they are the correct part numbers.
All contacts from the relays to there specific destinations are all good, no broken wire or connections.
I am getting power to the fuel injectors , but no ground. the ground come from the LH pin 13.
the male female connector on the crank sensor was broken, I don't know if the part was actually bad.
I have replaced the crank sensor with a brand new one from 928 specialists
118.00 did not help, I checked the connection from the sensor to the EZF
and the connections is fine.
I took the fuel pump relay and the LA relay out and jumpered them, It did not help.
the fuel pump only runs if the relay is jumpered or I run a straight hot line to the pump.
with the pump jumpered I have pressure and spark to the plugs, the injector are not getting a signal !!!
Can anyone tell me why?
If you read previous post dozman is telling me this LH unit is fine.
My crank sensor is new.
please help thank you
02-04-2006, 05:08 PM
#44
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Hello all I am very happy to say my car is running although I'm not sure what actually fixed it because of a few thing I did in the beginning when it didn't start. the first thing I was playing with were the relays and I had more than a few out at one time and I ended up replacing three of them the LH XXV the EZF XVI and the fuel pump XX so I put the new relays in and ( the others that I had out, one being the kick down relay ) and it didn't start so I kept looking for what was wrong. I thought it was the LH unit so then I bought one from DOZMAN, used and gave him the one I had from my car, it did not start and at that time a few of the people that posted had suggested a crank sensor so I put that in and it did not start, so I was talking to Rich from Electroniik Repair because ( and I'm sorry DOZMAN ) I still did know if in fact the LH was any good, Rich sent me one that he had in stock ( and told me to make sure the correct relay is in the kick down plug ) so I received the LH from Rich and was going through my check list and the kick down relay was switched with the abs relay next to it, I put it in the proper place and put Rich's LH unit in the car and it started right up.
I have to say at this time with working on this on and off sense July I am very happy !!!!!!!!!!!!!!
So then I put the LH from DOZMAN in and the car runs , still very happy
OK knowing that the relay was a very big factor but not the problem I can not report to all the people
here that have help me with this what the real problem was.
Was it one of the 3 relays that I replaced in the beginning ?
Was it the LH unit , I don't know this because DOZMAN got rid of the one I gave him when I bought a used one from him and he never said if he tested it or what happened to it, so that is an unknown.
Or was it the crank sensor?
I don't know because none of these things where working without the correct relay in the kick down
plug.
I hope this will help someone else with the same problem.
Thank you all again for helping me with this and to tell you the truth at this point I don't care what the problem was I am just soooooooo happy my car is runnnnnnnnnning!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Thank you thank you thank you!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!
I have to say at this time with working on this on and off sense July I am very happy !!!!!!!!!!!!!!
So then I put the LH from DOZMAN in and the car runs , still very happy
OK knowing that the relay was a very big factor but not the problem I can not report to all the people
here that have help me with this what the real problem was.
Was it one of the 3 relays that I replaced in the beginning ?
Was it the LH unit , I don't know this because DOZMAN got rid of the one I gave him when I bought a used one from him and he never said if he tested it or what happened to it, so that is an unknown.
Or was it the crank sensor?
I don't know because none of these things where working without the correct relay in the kick down
plug.
I hope this will help someone else with the same problem.
Thank you all again for helping me with this and to tell you the truth at this point I don't care what the problem was I am just soooooooo happy my car is runnnnnnnnnning!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Thank you thank you thank you!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!
