fuel injectors not pulsing Starved for fuel I have fuel pressure
12-20-2012, 01:46 AM
#16
Three Wheelin'
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Mine did this start, run 3 seconds, die thing. I never was really convinced but I think it was due to air getting in the fuel line during a filter change. No one ever talks about bleeding the fuel system but it seemed to have worked for me. Just a thought...Bruce
12-20-2012, 02:18 PM
#17
Changed my fuel filter 24 months / 4k ago and all has been fine..
12-21-2012, 12:16 PM
#18
Going to clean the grounds passenger side for the computer, injectors and O2 that are above the PORSCHE on the heads. The first one is easy to get to , it was dirty but no corrosion...the second one is hidden by the valve and tube for the air pump , how does that get removed? Appears the valve is bolted to engine?
I can't see anything that secures it ...
I can't see anything that secures it ...
12-21-2012, 01:42 PM
#19
Nordschleife Master
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Actually the noid light should be off with the key on. It will flash as you turn over if the injectors are being grounded. The noid light goes inline with the signal to turn on.
12-24-2012, 11:51 AM
#20
Just a little update.........Picked up the noid set , no pulse.
I do get 12v at the injector with the ignition on.
There is spark. Have not checked fuel pressure , but the engine does catch for a second before dying.
Waiting for my Fuel injector Relay from Roger, will report back once that gets here..
Also cleaned ground #1 (the accessable one) , the second one is hidden by the valve for the air pump, how do you remove the valve to access that ground?
I do get 12v at the injector with the ignition on.
There is spark. Have not checked fuel pressure , but the engine does catch for a second before dying.
Waiting for my Fuel injector Relay from Roger, will report back once that gets here..
Also cleaned ground #1 (the accessable one) , the second one is hidden by the valve for the air pump, how do you remove the valve to access that ground?
12-25-2012, 02:01 PM
#21
Sounds like Green Wire may be the culprit. Before I throw down and buy one , does anyone have a spare or extra I can try to determine the failure? PM me if you may have any suggestions . Merry Christmas all!
12-25-2012, 02:43 PM
#22
Rennlist Member
The ground located above the "O" in PORSCHE on the cam cover is accessed by removing the air diverter valve and hoses. Not as hard as it seems. Feel around it, you will find the 10mm bolts.
I'd be polishing the electrical panel and replacing all fuses, too.
The injector relay can be bypassed with a three way jumper to aid troubleshooting.
Surprised you haven't mentioned that, nor has anyone else. That's an important step.
That, combined with noid light, should immediately give you satisfaction.
In fact, its possible for the jumper to work, and the new relay NOT work, if the panel and fuses and other electrical ground and power related connections are dirty.
I don't ever touch a still-intact green wire. Cross that bridge after electrcial cleanup.
I'd be polishing the electrical panel and replacing all fuses, too.
The injector relay can be bypassed with a three way jumper to aid troubleshooting.
Surprised you haven't mentioned that, nor has anyone else. That's an important step.
That, combined with noid light, should immediately give you satisfaction.
In fact, its possible for the jumper to work, and the new relay NOT work, if the panel and fuses and other electrical ground and power related connections are dirty.
I don't ever touch a still-intact green wire. Cross that bridge after electrcial cleanup.
12-25-2012, 03:40 PM
#23
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Just a little update.........Picked up the noid set , no pulse.
I do get 12v at the injector with the ignition on.
There is spark. Have not checked fuel pressure , but the engine does catch for a second before dying.
Waiting for my Fuel injector Relay from Roger, will report back once that gets here..
Also cleaned ground #1 (the accessable one) , the second one is hidden by the valve for the air pump, how do you remove the valve to access that ground?
I do get 12v at the injector with the ignition on.
There is spark. Have not checked fuel pressure , but the engine does catch for a second before dying.
Waiting for my Fuel injector Relay from Roger, will report back once that gets here..
Also cleaned ground #1 (the accessable one) , the second one is hidden by the valve for the air pump, how do you remove the valve to access that ground?
No matter what pressure you have, if the noid light does not flash , you will NEVER start the car. Fix that problem first. You will likely find that that is the only problem you have.
The ground located above the "O" in PORSCHE on the cam cover is accessed by removing the air diverter valve and hoses. Not as hard as it seems. Feel around it, you will find the 10mm bolts.
I'd be polishing the electrical panel and replacing all fuses, too.
The injector relay can be bypassed with a three way jumper to aid troubleshooting.
Surprised you haven't mentioned that, nor has anyone else. That's an important step.
That, combined with noid light, should immediately give you satisfaction.
In fact, its possible for the jumper to work, and the new relay NOT work, if the panel and fuses and other electrical ground and power related connections are dirty.
I don't ever touch a still-intact green wire. Cross that bridge after electrcial cleanup.
I'd be polishing the electrical panel and replacing all fuses, too.
The injector relay can be bypassed with a three way jumper to aid troubleshooting.
Surprised you haven't mentioned that, nor has anyone else. That's an important step.
That, combined with noid light, should immediately give you satisfaction.
In fact, its possible for the jumper to work, and the new relay NOT work, if the panel and fuses and other electrical ground and power related connections are dirty.
I don't ever touch a still-intact green wire. Cross that bridge after electrcial cleanup.
12-26-2012, 10:19 PM
#26
Rennlist Member
The injector relay on the L-jet cars has an "extra" 87pin, sometimes its labled 87, sometimes labled 87a.
30 to 87 to 87
or
30 to 87 to 87a.
Does that help?
If not, I can post some pictures.
A search might find some pictures also, I don't remember.
Another way to approach the troubleshooting is putting a voltmeter's electrodes in the fusepanel slots of other remaining two electrodes that engergize the relay. When you turn the ignition, voltage should register.
30 to 87 to 87
or
30 to 87 to 87a.
Does that help?
If not, I can post some pictures.
A search might find some pictures also, I don't remember.
Another way to approach the troubleshooting is putting a voltmeter's electrodes in the fusepanel slots of other remaining two electrodes that engergize the relay. When you turn the ignition, voltage should register.
12-27-2012, 12:48 PM
#27
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the relay has a schematic printed on it and shows the current path, the small swinging door is the contact which opens and closes. You can also pull the relay, pry off the relay cover and wedge the contact points together with a toothpick then plug it in as a test..... That assures you do not jumper wire the wrong slots on the fuse board !!
12-27-2012, 06:11 PM
#28
the relay has a schematic printed on it and shows the current path, the small swinging door is the contact which opens and closes. You can also pull the relay, pry off the relay cover and wedge the contact points together with a toothpick then plug it in as a test..... That assures you do not jumper wire the wrong slots on the fuse board !!
Could my jetronic be dead? Why else (other then a ground) would the injectors not get pulse?
12-27-2012, 06:41 PM
#29
Rennlist Member
Check seating of every one of the electrodes at CE panel plug X.
That is the plug that distributes pulse to injectors.
Put a voltmeter across the OTHER remaining two female terminals where the injector relay sits.
When you turn key, you should see power to the voltmeter (to energize the relay you tried jumpering earlier).
Check the little red positive wire on battery... that feeds the panel.
Replace thermo time switch. It powers the 9th injector (cold start) and if it fails the car will show symptoms described. (Not sure if it interupts injectors, but causes no start after brief occasional fire). This happened to both my 84 USA cars. Notorious failure point when weather changes to below 50 degrees or so.
That is the plug that distributes pulse to injectors.
Put a voltmeter across the OTHER remaining two female terminals where the injector relay sits.
When you turn key, you should see power to the voltmeter (to energize the relay you tried jumpering earlier).
Check the little red positive wire on battery... that feeds the panel.
Replace thermo time switch. It powers the 9th injector (cold start) and if it fails the car will show symptoms described. (Not sure if it interupts injectors, but causes no start after brief occasional fire). This happened to both my 84 USA cars. Notorious failure point when weather changes to below 50 degrees or so.
12-27-2012, 07:45 PM
#30
Check seating of every one of the electrodes at CE panel plug X.
That is the plug that distributes pulse to injectors.
Put a voltmeter across the OTHER remaining two female terminals where the injector relay sits.
When you turn key, you should see power to the voltmeter (to energize the relay you tried jumpering earlier).
Check the little red positive wire on battery... that feeds the panel.
Replace thermo time switch. It powers the 9th injector (cold start) and if it fails the car will show symptoms described. (Not sure if it interupts injectors, but causes no start after brief occasional fire). This happened to both my 84 USA cars. Notorious failure point when weather changes to below 50 degrees or so.
That is the plug that distributes pulse to injectors.
Put a voltmeter across the OTHER remaining two female terminals where the injector relay sits.
When you turn key, you should see power to the voltmeter (to energize the relay you tried jumpering earlier).
Check the little red positive wire on battery... that feeds the panel.
Replace thermo time switch. It powers the 9th injector (cold start) and if it fails the car will show symptoms described. (Not sure if it interupts injectors, but causes no start after brief occasional fire). This happened to both my 84 USA cars. Notorious failure point when weather changes to below 50 degrees or so.
When you say the Other two , meaning not 30/87/87 ? The other two ?? I think is that 85/86 ? Set the multi meter to volts or ohm ?
Cleaned red wire the other day, looked good, also do get 12v at terminal 30 on the relay socket , so safe to assume the red wire at the battery is sending signal?
Where is the Thero time switch located?