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nigolusa
Is anybody willing to help me diagnose my starting problem? I live near the Rose Bowl. Car cannot be driven. Willing to compensate for efforts. Thank you!!!
MBowman325
I'm not local, I'm sure someone will pipe up.

But -- what is is not doing? No crank, crank won't start.

Is it still FI (L-Jet / D-Jet) or carb(s)?

Did it used to work?
nigolusa
QUOTE(MBowman325 @ Mar 23 2009, 10:37 AM) *

I'm not local, I'm sure someone will pipe up.

But -- what is is not doing? No crank, crank won't start.

Is it still FI (L-Jet / D-Jet) or carb(s)?

Did it used to work?



It was sort of working but the fuel pump was bad.

Installed a new fuel pump, and gas tank with new gaskets, lines, etc.

Everything is wired correctly. Touched fuel pump wire to positive and can hear the fuel pump working.

When the key is on, and I push the flap on the AFM, the fuel pump does not activate?
Also, when turning the key to start there is a delay, then the starter turns, but the engine doesn’t fire. The starter just turns over and over.

I checked the dual relay, also checked that power is coming to the socket. All seems to be ok.

Since I’m a newbie just learning this stuff, I’m at a total loss at this stage.
MBowman325
If you hear the pump running, are you sure that you hooked everything up properly when you redid the hoses?

I ran into a similiar issue on the way back from LA - the car died and I couldn't get is started. Wound up jumpering relay terminals on the board and Greg hooked me up with a relay in Phoenix. I later found out that that should not have worked since the L-Jets use the dual relay, but it got me outta the rest area west of the city. (I couldn't hear my pump running unless I jumpered it to battery)

http://www.pelicanparts.com/914/technical_...4_18fi_diag.htm
MBowman325
Here's another article to look over as well
http://autoatlanta.com/tech/fuel_injection.html
So.Cal.914
Is there spark? Is fuel passing through the injectors?
turbo2
QUOTE(nigolusa @ Mar 23 2009, 09:30 AM) *

Is anybody willing to help me diagnose my starting problem? I live near the Rose Bowl. Car cannot be driven. Willing to compensate for efforts. Thank you!!!


Hi,

Does any one out there have pics of how the plumbing on the L Jet should be rigged both air hoses and fuel hoses.

Just bought a 74 1.8 lit which has been standing for 17 yrs, I wanted a project and certainly got one. The way it's set up now is not right as the fuel pump is rigged directly to the ignition switch and the fuel pressure regulator is bypassed.

yeahmag
I'm in Pasadena, CA and can help. PM me for more information.
Cevan
Something is not right if the fuel pump doesn't run with the key on and the flap open. Do you hear the dual relay click when you do this? You should.

With the key on, you're powering one half of the relay. See if that part is working. Find terminal 88a on the backside of the socket. With the relay in, you should have 12 volts there with the key on. If not, the relay is bad.

If you got 12 volts there, see if the harness between the relay and AFM is good. With the key on, you should have 12 volts at terminal 39 on the AFM.

If you get 12 volts there, turn the key to on and open the AFM flap. You're sending 12 volts back to the other side of the relay, terminal 86b.

If you get 12 volts there, you should be powering the other side of the relay and should be getting 12 volts at 88c and 88d (with the relay installed of course).

If all of this checks out, then I'd say there is a problem with the wiring to your fuel pump. Check to see if you're getting 12 volts to the pump.

Here is a good diagnostics website for the L-Jet system.




jim_hoyland
Is the connector attached to the AFM ?
zonedoubt
QUOTE(jim_hoyland @ Mar 23 2009, 01:55 PM) *

Is the connector attached to the AFM ?


Also check the condition of the pins on the connector. I ended up replacing a few of the crimped pins because the connection was crap.
nigolusa
QUOTE(Cevan @ Mar 23 2009, 12:15 PM) *

Something is not right if the fuel pump doesn't run with the key on and the flap open. Do you hear the dual relay click when you do this? You should.

With the key on, you're powering one half of the relay. See if that part is working. Find terminal 88a on the backside of the socket. With the relay in, you should have 12 volts there with the key on. If not, the relay is bad.

If you got 12 volts there, see if the harness between the relay and AFM is good. With the key on, you should have 12 volts at terminal 39 on the AFM.

If you get 12 volts there, turn the key to on and open the AFM flap. You're sending 12 volts back to the other side of the relay, terminal 86b.

If you get 12 volts there, you should be powering the other side of the relay and should be getting 12 volts at 88c and 88d (with the relay installed of course).

If all of this checks out, then I'd say there is a problem with the wiring to your fuel pump. Check to see if you're getting 12 volts to the pump.

Here is a good diagnostics website for the L-Jet system.



Key on, relay in, 88a producing no voltage (pic attached)
No voltage to 39 on AFM either.

SHould there be voltage on the socket, without the relay? There isn't any.


Click to view attachment
nigolusa
Also, does it matter that I've disconnected the turn signal/wiper lever harness?
nigolusa

Turned the key to start. 15 second delay, THEN, the starter turned over? WHAT THE??? chair.gif screwy.gif headbang.gif
Cevan
QUOTE(nigolusa @ Mar 23 2009, 08:11 PM) *

Key on, relay in, 88a producing no voltage
No voltage to 39 on AFM either.

Your relay is bad.

QUOTE(nigolusa @ Mar 23 2009, 08:11 PM) *

SHould there be voltage on the socket, without the relay? There isn't any.

There should be 12 volts at the socket even with the key off on 88z and 88y.

With the key on, you should also get 12 volts at 86c.
nigolusa
QUOTE(Cevan @ Mar 23 2009, 05:29 PM) *

QUOTE(nigolusa @ Mar 23 2009, 08:11 PM) *

Key on, relay in, 88a producing no voltage
No voltage to 39 on AFM either.

Your relay is bad.

QUOTE(nigolusa @ Mar 23 2009, 08:11 PM) *

SHould there be voltage on the socket, without the relay? There isn't any.

There should be 12 volts at the socket even with the key off on 88z and 88y.

With the key on, you should also get 12 volts at 86c.



Open socket only, no relay in:

Key off, I get voltage at 88z and 88Y
Key on, I get voltage at 86C


nigolusa
QUOTE(nigolusa @ Mar 23 2009, 05:37 PM) *

QUOTE(Cevan @ Mar 23 2009, 05:29 PM) *

QUOTE(nigolusa @ Mar 23 2009, 08:11 PM) *

Key on, relay in, 88a producing no voltage
No voltage to 39 on AFM either.

Your relay is bad.

QUOTE(nigolusa @ Mar 23 2009, 08:11 PM) *

SHould there be voltage on the socket, without the relay? There isn't any.

There should be 12 volts at the socket even with the key off on 88z and 88y.

With the key on, you should also get 12 volts at 86c.



Open socket only, no relay in:

Key off, I get voltage at 88z and 88Y
Key on, I get voltage at 86C



Anybody have a dual relay for sale? flag.gif
zonedoubt
QUOTE(nigolusa @ Mar 23 2009, 06:35 PM) *

Anybody have a dual relay for sale? flag.gif


Pony up and get a new one. It's not worth the hassle dealing with 30+ year old electrical parts.

This is a good deal: http://www2.cip1.com/ProductDetails.asp?Pr...332%2D514%2D120
nigolusa
QUOTE(zonedoubt @ Mar 23 2009, 06:45 PM) *

QUOTE(nigolusa @ Mar 23 2009, 06:35 PM) *

Anybody have a dual relay for sale? flag.gif


Pony up and get a new one. It's not worth the hassle dealing with 30+ year old electrical parts.

This is a good deal: http://www2.cip1.com/ProductDetails.asp?Pr...332%2D514%2D120



Cheaper: http://www.bavauto.com/fland.asp?part=0%20...332%20514%20120
nigolusa
Well the dual relay came. Got voltage everywhere. Pushed AFM door and fuel pump is active. Removed fuel line, pushed AFM door, fuel discharging. All hooked up correctly.

Turn the key, nothing!!! Huge delay, then starter finally cranks, but engine doesn't fire.

Any ideas anybody.
zonedoubt
QUOTE(nigolusa @ Mar 30 2009, 07:44 PM) *

Well the dual relay came. Got voltage everywhere. Pushed AFM door and fuel pump is active. Removed fuel line, pushed AFM door, fuel discharging. All hooked up correctly.

Turn the key, nothing!!! Huge delay, then starter finally cranks, but engine doesn't fire.

Any ideas anybody.


Faulty ignition switch (easy & cheap to replace), poor wiring between switch and relay (trace & replace), poor starter connections (clean them up).
nigolusa
QUOTE(zonedoubt @ Mar 31 2009, 11:11 AM) *

QUOTE(nigolusa @ Mar 30 2009, 07:44 PM) *

Well the dual relay came. Got voltage everywhere. Pushed AFM door and fuel pump is active. Removed fuel line, pushed AFM door, fuel discharging. All hooked up correctly.

Turn the key, nothing!!! Huge delay, then starter finally cranks, but engine doesn't fire.

Any ideas anybody.


Faulty ignition switch (easy & cheap to replace), poor wiring between switch and relay (trace & replace), poor starter connections (clean them up).



Thanks will try
benalishhero
Are the injectors firing? Have you checked for spark? How about the grounds to the duel relay?

I've also experienced the spade connectors pushing out of the relay connectors as you plug it in.
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