1989 porsche 928 no start
01-21-2010, 01:15 PM
#46
I don't work on cars in the wet. But when its dry, I may try. Who are you 88porsche928?
01-22-2010, 11:08 AM
#49
I'm asking because maybe a few friends and I can help. When it dries up and warms up - of course. 
I moved to San Diego so I wouldn't have to work on cars in the cold.
I moved to San Diego so I wouldn't have to work on cars in the cold.
01-22-2010, 12:39 PM
#51
Chronic Tool Dropper
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Save the vodka for the celebration AFTER the car is running...
01-30-2010, 07:59 PM
#53
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where is plug w
OK - The problem is that either there is no power to the injectors, or the power is shorted in the injector harness.
Back to basics:
First thing to do is to go to the battery and carefully clean all of the connections, especially the medium-sized red wires on the positive terminal. Then check to make sure that Plug W in the Central Electric Panel is fully seated.
If that doesn't fix the problem, pull Relay XXV, the LH relay. Find Terminal 30, and check for battery power there. If there is no power, check the red wires again. If there is power, install a TEMPORARY jumper between Terminals 30 and 87.
If that doesn't fix the problem, go to the Ignition Monitoring Relay on the right kick panel, and with the jumper in the LH Relay socket in place, check for battery power on the red and red/yellow wires in Terminal 87. If there is battery power on 87, check for battery power on the red/green wire in Terminal A1 and the red/yellow wire in Terminal A2. If you have power here, you should have a glowing noid light on any injector.
Be sure to remove the temporary jumper in the LH Relay socket.
Back to basics:
First thing to do is to go to the battery and carefully clean all of the connections, especially the medium-sized red wires on the positive terminal. Then check to make sure that Plug W in the Central Electric Panel is fully seated.
If that doesn't fix the problem, pull Relay XXV, the LH relay. Find Terminal 30, and check for battery power there. If there is no power, check the red wires again. If there is power, install a TEMPORARY jumper between Terminals 30 and 87.
If that doesn't fix the problem, go to the Ignition Monitoring Relay on the right kick panel, and with the jumper in the LH Relay socket in place, check for battery power on the red and red/yellow wires in Terminal 87. If there is battery power on 87, check for battery power on the red/green wire in Terminal A1 and the red/yellow wire in Terminal A2. If you have power here, you should have a glowing noid light on any injector.
Be sure to remove the temporary jumper in the LH Relay socket.
01-30-2010, 08:04 PM
#54
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where is terminal 1a
The meter tests I shared are extremely definitive when diagnosing harness problems on '89+ cars. Did you find a short in the harness, an open circuit, or a short to ground? If not, it's possible to create new problems while 'fixing' the old harness, where no problems existed before.
Test procedure simplified:
-- With the ignition protection relay out:
A1) Ohms between LH connector 18 and relay socket terminal 1A should be about 4 ohms. Much more means an open in a connector, injector coil, or a broken conductor in the harness.
A2) Ohms between LH connector 18 and relay socket terminal 1A (same test...) should be about 4 ohms. Less than 2 ohm means you have an internal short between conductors in the harness. This is the damage you reported when cutting open that first connector boot.
B1) Ohms between LH connector 18 and relay socket terminal 1B should be about 4 ohms. Much more means an open in a connector, injector coil, or a broken conductor in the harness.
B2) Ohms between LH connector 18 and relay socket terminal 1B (same test...) should be about 4 ohms. Less than 2 ohm means you have an internal short between conductors in the harness. This is the damage you reported when cutting open that first connector boot.
C) Ohms between LH connector 18 and ground should be infinite. If they are less than 1 ohm, you have a short to ground on the LH side of the harness, and it could be at any injector.
D) Ohms between LH connector 18 and ground should be infinite. If they are around 4 ohms, you have a short to ground on the power side of the harness, and it could be at any injector. Proceed to E1 and E2 to narrow down where it might be.
-- E1) Ohms between protection relay socket at 1A and ground should be infinite. If they are less than 1 ohm, you have a short to ground on the power side of the harness, and it could be at injector 2, 3, 5, or 8.
-- E2) Ohms between protection relay socket at 1B and ground should be infinite. If they are less than 1 ohm, you have a short to ground on the power side of the harness, and it could be at injector 1, 4, 6, or 7.
*** Do these tests BEFORE you remove any of the injector connectors. The resistance values presume that you still have all the injectors plugged in. Each injector coil is real close to 16 ohms. Two coils connected is about 8 ohms, 3 connected is a little over 5 ohms, four connected is 4 ohms. On the '89, the harness is separated on the power side and is fed through those two contacts on the protection relay; with the relay removed they are connected only on the ground (LH brain) side, and to the brain through LH terminal 18. With that protection relay installed, the power sides are connected to each other through the relay contacts, and also to the heating coil on the oxygen sensor, even when the LH power relay is not energized.
PLEASE POST WHAT YOU FIND WITH YOUR METER.
--
Test procedure simplified:
-- With the ignition protection relay out:
A1) Ohms between LH connector 18 and relay socket terminal 1A should be about 4 ohms. Much more means an open in a connector, injector coil, or a broken conductor in the harness.
A2) Ohms between LH connector 18 and relay socket terminal 1A (same test...) should be about 4 ohms. Less than 2 ohm means you have an internal short between conductors in the harness. This is the damage you reported when cutting open that first connector boot.
B1) Ohms between LH connector 18 and relay socket terminal 1B should be about 4 ohms. Much more means an open in a connector, injector coil, or a broken conductor in the harness.
B2) Ohms between LH connector 18 and relay socket terminal 1B (same test...) should be about 4 ohms. Less than 2 ohm means you have an internal short between conductors in the harness. This is the damage you reported when cutting open that first connector boot.
C) Ohms between LH connector 18 and ground should be infinite. If they are less than 1 ohm, you have a short to ground on the LH side of the harness, and it could be at any injector.
D) Ohms between LH connector 18 and ground should be infinite. If they are around 4 ohms, you have a short to ground on the power side of the harness, and it could be at any injector. Proceed to E1 and E2 to narrow down where it might be.
-- E1) Ohms between protection relay socket at 1A and ground should be infinite. If they are less than 1 ohm, you have a short to ground on the power side of the harness, and it could be at injector 2, 3, 5, or 8.
-- E2) Ohms between protection relay socket at 1B and ground should be infinite. If they are less than 1 ohm, you have a short to ground on the power side of the harness, and it could be at injector 1, 4, 6, or 7.
*** Do these tests BEFORE you remove any of the injector connectors. The resistance values presume that you still have all the injectors plugged in. Each injector coil is real close to 16 ohms. Two coils connected is about 8 ohms, 3 connected is a little over 5 ohms, four connected is 4 ohms. On the '89, the harness is separated on the power side and is fed through those two contacts on the protection relay; with the relay removed they are connected only on the ground (LH brain) side, and to the brain through LH terminal 18. With that protection relay installed, the power sides are connected to each other through the relay contacts, and also to the heating coil on the oxygen sensor, even when the LH power relay is not energized.
PLEASE POST WHAT YOU FIND WITH YOUR METER.
--
01-30-2010, 08:20 PM
#55
Team Owner
plug W is on the CE panel at the right bottom it should have a hand scrawled letter on it.
When you pull it off you will see little numbers on the female mating surface look closely ( for the W connector it might be red or yellow)
A1 is for the ignition monitoring relay just look at the relay the pins should be numbered
When you pull it off you will see little numbers on the female mating surface look closely ( for the W connector it might be red or yellow)
A1 is for the ignition monitoring relay just look at the relay the pins should be numbered
01-30-2010, 09:54 PM
#56
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i found two discoveries one this random plug was unplugged and hidding behind the smaller woden piece disconnected, i cannot find where it belonds two, two the w plug seems loose at the bottom and i dont know how to make it tight i kept pushing it in, i tried starting the car while holding down pressure on it and it still did not turn on.
01-30-2010, 10:23 PM
#57
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Difficult to tell from the dark photo. Carefully check the harness to the plug, and list all of the wire colors in the harness.
Check the socket for plug W and ensure that it is locked in place. There is a locking bar in the center of the row of plugs that must be slid aside to remove the plugs. Make sure that it is in place - if so, slide it aside, remove Plug W and check the plug and socket, insert it fully in the socket and hold it there while you slide the bar back to the locked position.
Have you cleaned the connections on the battery?
Check the socket for plug W and ensure that it is locked in place. There is a locking bar in the center of the row of plugs that must be slid aside to remove the plugs. Make sure that it is in place - if so, slide it aside, remove Plug W and check the plug and socket, insert it fully in the socket and hold it there while you slide the bar back to the locked position.
Have you cleaned the connections on the battery?
01-30-2010, 10:52 PM
#58
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i have cleaned the connection to the battery. that plug is black. im going to have to buy a whiter more powerful light to view every thing. i just cannot find what that could plug into
my hopes of plugging that in and having the car start up have just been crushed by fraggle, im going to get another multimeter or use the one I use at work.