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914World.com _ 914World Garage _ Ljet experts.
Posted by: 914itis Apr 18 2013, 08:08 PM
My brother in Georgia is slowly putting back together a 75 ljet that I gave him. He's doing everything with my help over the phone.
For some reason he refuses to post here.
Today, we finally got the engine started. It starts for a couples seconds and dies.
The air cleaner assembly is still out. I know with djet the car will idle without the air cleaner. Is it the same with ljet or should we start looking elsewhere?
Posted by: timothy_nd28 Apr 18 2013, 08:15 PM
Is the air flow meter still attached to the rubber boot?
Posted by: ConeDodger Apr 18 2013, 08:24 PM
Battery fully charged I assume?
Fuel pressure?
There must not be any vacuum leaks. Vacuum leaks confound the ECU.
Most EFI problems are really not EFI problems...
Posted by: 914itis Apr 18 2013, 08:34 PM
Is the air flow meter still attached to the rubber boot?
I will ask him in the morning and report back.
Posted by: 914itis Apr 18 2013, 08:37 PM
Battery fully charged I assume?
Fuel pressure?
There must not be any vacuum leaks. Vacuum leaks confound the ECU.
Most EFI problems are really not EFI problems...
Yes battery is fully charged, new vacuums all around.
Posted by: Chris H. Apr 18 2013, 08:39 PM
There must not be any vacuum leaks. Vacuum leaks confound the ECU.
Sure sounds like a vacuum leak. LJET has very little tolerance for those...
Posted by: 914itis Apr 18 2013, 08:39 PM
I forgot to mention that if he cranks it again it starts right away, idles for about 5 -10 seconds
Posted by: Mark Henry Apr 18 2013, 08:43 PM
Vacuum leaks, get new hoses, there's even a seal in the oil cap that must be perfect.
BTDT
Posted by: jim_hoyland Apr 18 2013, 08:50 PM
One of the wires at the dual relay is not making good contact or the dual relay is shot. There is a test you can do to verify the dual relay is good. PM me your email and I'll send you a step by step copy
Posted by: messix Apr 18 2013, 09:14 PM
the crank case must be a sealed unit, ie the oil cap on and tight, all breathers connected to the airbox and intake.
Posted by: timothy_nd28 Apr 18 2013, 09:18 PM
I don't think the air flow meter is connected. You stated that the car runs at idle for a few moments before it stumbles and dies. Having the AFM's 6 pin or 7 pin connector not attached to the AFM can cause this. The fuel pump is activated thru the dual relay. The dual relay first receives voltage from the ignition switch at the "start" position. As soon as you let go of the key, and it springs back to the "on" position, you lose the voltage going to the dual relay. (A hand off occurs at this point) With the engine idling, the AFM supplies voltage to the dual relay. Having no AFM connected, the dual relay will never receives this voltage, thus the fuel pump stops and the engine dies. I'm pretty sure if you add a jumper from pin 88d on the dual relay to the positive battery post, the car will continue to idle indefinitely. However, with no AFM, if you blip the throttle the engine will die.
Posted by: skeates Apr 18 2013, 09:29 PM
I don't think the air flow meter is connected. You stated that the car runs at idle for a few moments before it stumbles and dies. Having the AFM not installed, or the 7 pin connector not attached to the AFM can cause this. The fuel pump is activated thru the dual relay. The dual relay first receives voltage from the ignition switch at the "start" position. As soon as you let go of the key, and it springs back to the "on" position, you lose the voltage going to the dual relay. (A hand off occurs at this point) With the engine idling, the AFM supplies voltage to the dual relay. Having no AFM connected, the dual relay will never receives this voltage, thus the fuel pump stops and the engine dies. I'm pretty sure if you add a jumper from pin 88d on the dual relay to the positive battery post, the car will continue to idle indefinitely. However, with no AFM, if you blip the throttle the engine will die.
sounds like the plug on afm isn't connectected.
Posted by: r_towle Apr 18 2013, 09:38 PM
http://manuals.type4.org/ljet/
Posted by: 914itis Apr 18 2013, 09:43 PM
Thanks and I have a lot of information to start troubleshooting. Stay tune......
Posted by: computers4kids Apr 18 2013, 09:47 PM
I don't think the air flow meter is connected. You stated that the car runs at idle for a few moments before it stumbles and dies. Having the AFM not installed, or the 7 pin connector not attached to the AFM can cause this. The fuel pump is activated thru the dual relay. The dual relay first receives voltage from the ignition switch at the "start" position. As soon as you let go of the key, and it springs back to the "on" position, you lose the voltage going to the dual relay. (A hand off occurs at this point) With the engine idling, the AFM supplies voltage to the dual relay. Having no AFM connected, the dual relay will never receives this voltage, thus the fuel pump stops and the engine dies. I'm pretty sure if you add a jumper from pin 88d on the dual relay to the positive battery post, the car will continue to idle indefinitely. However, with no AFM, if you blip the throttle the engine will die.
sounds like the plug on afm isn't connectected.
Posted by: timothy_nd28 Apr 18 2013, 10:04 PM
Thanks and I have a lot of information to start troubleshooting. Stay tune......
That's good brotherly love, giving a 914 to your brother.
Posted by: 914itis Apr 18 2013, 10:09 PM
Thanks and I have a lot of information to start troubleshooting. Stay tune......
That's good brotherly love, giving a 914 to your brother.
Thanks,
He would have done the same for me. He's always
his daily driver and his wife's. he claims that's because he is bored. Well well, he will be plenty busy with the 914
Posted by: tacm Apr 18 2013, 10:14 PM
email me at smccutcheon@motioncnc.com and I will send the L-jetronic service manual. I do agree with above, Air flow meter, or vacuum leak
Posted by: Jeff Bowlsby Apr 18 2013, 10:15 PM
His name is not Harvey is it?
Posted by: timothy_nd28 Jan 1 2018, 07:11 PM
Did your brother ever get this figured out?
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