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> Won't Fire up with L-jet, WTF!!! Update on Page 2 post 35
Black22
post Apr 15 2012, 03:47 PM
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I have a new 1911 with L-jet. It was formerly a 1.8L stock engine that ran good. Trying to do the break in cycle but have no fuel.

I have spark and air, but injectors won't fire.

I can however jump the relay and get the fuel pump to run. I can also move the flap manually at the AFM and that will also trigger the pump to run with all the stock wiring in place.

I tried all the tests at the manuals.type4.org website. It passes all the tests.
Only one test is questionable though.

** Measure the resistance between ECU plug terminal 20 and system ground at terminal 17. The reading should be 52-78 Ohms. Mine reads 5.9 Ohms. That would suggest the dual relay is bad, so I install a brand new relay and that one reads 6.9 Ohms. WTH?

What am I missing?
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pilothyer
post Apr 15 2012, 03:52 PM
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The L-Jet system doesn't pressurize the fuel loop like the D-Jet does. The L-Jet pump only runs when the starter turns and causes the flap to open in the air flow meter. If you can open the flap while the key is on you should hear the pump run constantly. Of course after the engine starts the pump continues to run.
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Black22
post Apr 15 2012, 10:18 PM
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Alright, I checked it out a little more after the wife hit the sack.

Injectors are not firing. Pump is working. So I'm down to the ECU and the resistor pack. The resistor pack is in great shape. No broken wires. Any info on how to check an ECU? I've searched all day long and can't find a thread that answers my dilemma.
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falconfp2001
post Apr 15 2012, 10:56 PM
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QUOTE(Black22 @ Apr 15 2012, 09:18 PM) *

Alright, I checked it out a little more after the wife hit the sack.

Injectors are not firing. Pump is working. So I'm down to the ECU and the resistor pack. The resistor pack is in great shape. No broken wires. Any info on how to check an ECU? I've searched all day long and can't find a thread that answers my dilemma.


I found this a while back when considering converting to L jet.
http://www.bowlsby.net/914/Classic/zTN_Man08.pdf

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CrashDown
post Apr 15 2012, 10:59 PM
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Youve got waaaay more patience then me for that stuff. I was having runability issues with my FI on my 2.0L... and after 48hrs I ordered a set of Webers....

Hope ya figure it out dude!!
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falconfp2001
post Apr 16 2012, 12:04 AM
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QUOTE(falconfp2001 @ Apr 15 2012, 09:56 PM) *

QUOTE(Black22 @ Apr 15 2012, 09:18 PM) *

Alright, I checked it out a little more after the wife hit the sack.

Injectors are not firing. Pump is working. So I'm down to the ECU and the resistor pack. The resistor pack is in great shape. No broken wires. Any info on how to check an ECU? I've searched all day long and can't find a thread that answers my dilemma.


I found this a while back when considering converting to L jet.
http://www.bowlsby.net/914/Classic/zTN_Man08.pdf


L Jet is pretty reliable. You should consider the trigger points may be bad.
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Dave_Darling
post Apr 16 2012, 09:25 AM
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No trigger points in L-jet. It goes off the ignition signal.

Speaking of which: All the wires connected? There should be an "extra" one on the coil to pick up the ignition signal for the injection.

How's the dual relay doing?

--DD
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Black22
post Apr 16 2012, 11:00 AM
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QUOTE(Dave_Darling @ Apr 16 2012, 08:25 AM) *

No trigger points in L-jet. It goes off the ignition signal.

Speaking of which: All the wires connected? There should be an "extra" one on the coil to pick up the ignition signal for the injection.

How's the dual relay doing?

--DD


Yeah, no trigger points.

All wires are connected. The "extra" wire is connected to (-) side of coil. I originally thought the dual relay was the suspect. I installed a new in box dual relay with the same results.

I think I'm down to the ECU or the Resistor pack. Both of which are in good shape and worked prior to rebuild.

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76-914
post Apr 16 2012, 12:25 PM
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QUOTE(CrashDown @ Apr 15 2012, 09:59 PM) *

Youve got waaaay more patience then me for that stuff. I was having runability issues with my FI on my 2.0L... and after 48hrs I ordered a set of Webers....

Hope ya figure it out dude!!

Hope you kept your old FI pieces. After a few years of putzing w/ carbs you'll feel differently. Especially those moisture trapping Webers. Good luck!
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pt_700
post Apr 16 2012, 01:40 PM
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while not l-jet, my 1.7 had the same issue - no signal to the injectors.

ended up breaking down and taking to a real mechanic. after hours of checking the basics, he swapped ecu's with another car in his shop and it ran! perhaps someone local has an extra you could try?
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Black22
post Apr 16 2012, 02:00 PM
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I saw an ad in the classifieds for and ECU.

Do the part numbers have to match? His is a 74 and so is mine but my P/n is 280 000 103 / 022 906 021G

His is 280.000.090 and 473.906.021

Will these swap?
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timothy_nd28
post Apr 16 2012, 02:11 PM
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Mine didn't start up at first. Same issues your saying. Although the double relay was fine, it was the 2 connectors that plug into it. I'd double check the condition of the DBL relay connectors before you start replacing parts. Also, make sure the 3 white wires are attached to the gnd terminal on the engine tin. In addition to that, make sure your tranny ground is making good contact.
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Black22
post Apr 16 2012, 02:58 PM
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QUOTE(tim_nd @ Apr 16 2012, 01:11 PM) *

Mine didn't start up at first. Same issues your saying. Although the double relay was fine, it was the 2 connectors that plug into it. I'd double check the condition of the DBL relay connectors before you start replacing parts. Also, make sure the 3 white wires are attached to the gnd terminal on the engine tin. In addition to that, make sure your tranny ground is making good contact.


Double relay is good. I also have a 2nd brand new one that was of no help. Contacts at the relay were all checked and manually seated.

Grounds are connected and even better I ran an extra line from the common ground for the FI directly to the battery ground. No help.

Trans area ground point was degreased and wire brushed before engine install. A small amount of dielectric grease was applied before the strap was fastened.

I was very detailed in the prep and install of this engine. That's why I'm stumped. (IMG:style_emoticons/default/confused24.gif)

I was thinking of just ripping the harnesses apart and rewiring them...but that might take a while. (IMG:style_emoticons/default/barf.gif)
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timothy_nd28
post Apr 16 2012, 03:05 PM
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I believe you, I'm sure the dbl relay is good. I played this game last week, after the car sat for 15 years. I ended up soaking the 2 connectors that snap onto the double relay in a glass of coke cola. The reason I keep coming back to this, is due to what you said earlier. You had different resistance's when trying different relays.
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pt_700
post Apr 16 2012, 03:19 PM
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i'd search around as i seem to recal seeing a compatibility chart from Jeff Bowlsby. if you do end up replacing the ecu, i'd look for one with an adjustment knob for the idle mixture.

sorry, i was unable to locate that chart...

QUOTE(Black22 @ Apr 16 2012, 01:00 PM) *

I saw an ad in the classifieds for and ECU.

Do the part numbers have to match? His is a 74 and so is mine but my P/n is 280 000 103 / 022 906 021G

His is 280.000.090 and 473.906.021

Will these swap?

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timothy_nd28
post Apr 16 2012, 03:41 PM
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2 more silly questions. Is the yellow wire attached to the right terminal on that relay board?
When you jump out the fuel pump, and the pump stays on, have you tried starting the car?
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Black22
post Apr 16 2012, 03:50 PM
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QUOTE(tim_nd @ Apr 16 2012, 02:41 PM) *

2 more silly questions. Is the yellow wire attached to the right terminal on that relay board?
When you jump out the fuel pump, and the pump stays on, have you tried starting the car?


No questions are silly at this point.

Yes, Yellow wire is attached to the correct point on relay board. #II on 4 pole FI connection at relay board.

I did jump the fuel pump and tried to start, but injectors did not fire. I had them connected and firing into a jar. Dry as a bone.

Supply line was disconnected at fuel rail. Lines are circulating fuel when pump is jumped or AFM flap id held open.
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pilothyer
post Apr 16 2012, 04:08 PM
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Have you checked the temp sensor? Do you have a way to test the fuel loop pressure? I feel for you considering this L-Jet system worked before the rebuild.
A lot of things can happen to the fuel system and the injectors if much time passed during the rebuild, especially with today's gasoline
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Black22
post Apr 16 2012, 04:54 PM
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QUOTE(pilothyer @ Apr 16 2012, 03:08 PM) *

Have you checked the temp sensor? Do you have a way to test the fuel loop pressure? I feel for you considering this L-Jet system worked before the rebuild.
A lot of things can happen to the fuel system and the injectors if much time passed during the rebuild, especially with today's gasoline


Temp sensor:good
3 of the four injectors are NOS
Engine has been down for 4 months. All stored items had Marvel Mystery oil run through them prior to storage.
New SS fuel lines in tunnel and engine compartment
New fuel filter
Fuel tank cleaned out and new sock and copper washers installed
All fuel lines replaced with 30r9
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timothy_nd28
post Apr 16 2012, 05:04 PM
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You have fuel pump action, while depressing the AFM flap. However, you can't hear the fuel pump when the ignition switch is in the crank position? Can you verify this by measure voltage at the pump?
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