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malcolm2
Ok I think I am good on the seat belt relay. YLW and YLW/red are spliced. And I have checked for continuity all the way from the starter to the key on that wire.

I have spark, points checked too.

I have fuel pressure, about 40 psi, checked between p-side fuel rail and cold start valve.

Starter works fine

oil pressure builds, light goes out on the dash

Engine timing is still at rebuild setting...0 TDC.

Re-built FI & Ignition & Alt harnesses

I did have trouble with the key switch, so the steering wheel is out, levers are not connected and I turn a screw driver on the end of the key connector to fire the starter, should not be an issue, correct?

I got the L-jet trouble shooting "no start" pages to try tomorrow.

Any other ideas? I am baffled. confused24.gif
timothy_nd28
Can you post a few pics, so we can rule out anything obvious
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 12:58 AM) *

Can you post a few pics, so we can rule out anything obvious


anything specific you would like to see? I'll snap a few of the items I mentioned.

The Rats nest that is the seat belt relay, mostly. YLW and YLW/red are spliced. Anything else of concern here?
Click to view attachment

fuel pressure gauge (temporary) between the pass. fuel rail and the CSV. going down quickly after 2 15 seconds tries at starting.
Click to view attachment

coil and connections
Click to view attachment

Top of engine shot.
Click to view attachment


Relay plate, uncovered.
Click to view attachment

no steering wheel, control levers, key switch. turning the switch with a std screwdriver.
Click to view attachment

I can take additional shots, just let me know what.

Thanks,

Clark
jim_hoyland
My favorite no-start issues have been:
1. Yellow wire at rear of harness not connected to the 4 spade plug
2. Black ignition wire on negative side of coil
3. The 6-pin plug that goes into the AFM is unplugged or loose
4. The ground wire from the dual relay is not connected, it goes onto a spade in the middle of the engine case
5. White FI wire,along with tach wire, not on the negative terminal of coil
6. Lastly, a bad connection at the + battery of one of the red wires. Two reds go to the 14 pin connected at thr front of the relay board.

Good luck, been there; tell us what you find out
timothy_nd28
Okay, so the car turns over and you already verified spark and fuel pressure. I would double check and make sure you have the dropping resistors for the fuel injectors connected. Then turn your attention to the dual relay. With the ignition switch turned to the "on" position, measure pin 88a for voltage. You should see 12vdc, if this is true, remove the ECU connector and measure pin 10 for 12vdc.
Rockaria
QUOTE(jim_hoyland @ Jun 29 2013, 07:21 AM) *

My favorite no-start issues have been:
...
3. The 6-pin plug that goes into the AFM is unplugged or loose
...


Done this before... A few times.... So embarrassing dry.gif Harder to admit! My final solution, sell the 75 and buy a 73. All better.

Also check the resistor pack (The 4 cigaretts in a metal sleeve) they can come loose. (not only the connector... inside at the white parts, the connection can break.)
jim_hoyland
Another thing I would ask: Does the engine start for a second or two and then stop, or does it not start at all.

Your fuel pressure gauge indicates that the dual relay is working. When there is a lose DR wire or the DR is cooked, the fuel pressure gauge reads zero
malcolm2
Morning tests lead me to the Injectors. I pulled the electric connection from one injector and put the meter on the connections and tried to start the car. Got no reading on the meter. Checked continuity from the ECU to that injector and both wires are sound. BOWLSBY did all my harnesses.

Earlier question: ever start? No never fired at all, no gas on the plugs.
timothy_nd28
Did you have 12vdc on pin 10 on the ECU connector?
timothy_nd28
If you don't have 12v at pin 10 you won't have voltage at pins 14,15,32 and 33 either. Run a temp jumper on the dual relay pin 88a to the positive battery post and try starting the car.

BTW, You won't have much luck reading voltages at the fuel injector connector. The voltage will be a quick blip and most modern multimeters won't measure it. Unless you're using an analog meter, this would allow you to see the meter needle sweep back and forth.
jim_hoyland
I assume the resister pack is plugged in; you may want to test the dual relay at the resister terminal, see diagram below. With the key on the ircuit to the resisters should be hot. Diagram is a Top view...
Sleepin
Every time mine hasn't started (each time in the garage without any work done on it), I scream and cuss at it....walk away...curse at it every time that I walk past it for a few days...

Then when I try it again a few days later, she fires right up.

No BS...this has happened more than twice.
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 10:33 AM) *

Okay, so the car turns over and you already verified spark and fuel pressure. I would double check and make sure you have the dropping resistors for the fuel injectors connected. Then turn your attention to the dual relay. With the ignition switch turned to the "on" position, measure pin 88a for voltage. You should see 12vdc, if this is true, remove the ECU connector and measure pin 10 for 12vdc.



Yes 12v at both.

FOr those following or future problems.... page two of this link has the pin out for the ECU of the L-jet.

Bowlsby's L-Jet FI harness
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 01:10 PM) *


BTW, You won't have much luck reading voltages at the fuel injector connector. The voltage will be a quick blip and most modern multimeters won't measure it. Unless you're using an analog meter, this would allow you to see the meter needle sweep back and forth.


That is what I thought might happen. My meter is digital.
timothy_nd28
Good, now with the ECU connector off, measure pins 14,15,32,33 You should have 12volts on those as well
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 01:10 PM) *

If you don't have 12v at pin 10 you won't have voltage at pins 14,15,32 and 33 either. Run a temp jumper on the dual relay pin 88a to the positive battery post and try starting the car.



Since I have voltage at 88a, there is no since in jumping here, correct? I have voltage at 10 too.
timothy_nd28
QUOTE(malcolm2 @ Jun 29 2013, 12:16 PM) *

QUOTE(timothy_nd28 @ Jun 29 2013, 01:10 PM) *

If you don't have 12v at pin 10 you won't have voltage at pins 14,15,32 and 33 either. Run a temp jumper on the dual relay pin 88a to the positive battery post and try starting the car.



Since I have voltage at 88a, there is no since in jumping here, correct? I have voltage at 10 too.



correct, it would be redundant. Check those pins on the ECU connector that I described above.
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 03:16 PM) *

Good, now with the ECU connector off, measure pins 14,15,32,33 You should have 12volts on those as well


12 volts at all 4.
timothy_nd28
I'm not home, give me a hour to reply
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 03:52 PM) *

I'm not home, give me a hour to reply


ANY & ALL help is appreciated. I feel like I have tried everything! And everything is fresh and new, but still nuttin'! screwy.gif confused24.gif
timothy_nd28
Okay, with one meter lead on pin 10 (ECU connector) put the other meter lead on pin 5, then 16, then 17. You should have 12volts reading on your meter on all. (ignition switch turn to on while checking)

After that, check the resistance of pin 13 to ground.
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 04:36 PM) *

Okay, with one meter lead on pin 10 (ECU connector) put the other meter lead on pin 5, then 16, then 17. You should have 12volts reading on your meter on all. (ignition switch turn to on while checking)

After that, check the resistance of pin 13 to ground.


SOmething different this time.

10 & 5 = 12v
10 & 16 = 7v and rising 7.01...7.04...7.1...
10 & 17 =5.6v

13 to ground meter on 2k = 1.78
timothy_nd28
Pin 5, 16 and 17 should all be grounds. This could be the problem. The resistance check was for the CHT, which proves that you have it installed
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 05:26 PM) *

Pin 5, 16 and 17 should all be grounds. This could be the problem. The resistance check was for the CHT, which proves that you have it installed



Crazy voltage does seem to be a problem. So I should have gotten 12 volts between 10 and any ground? what does that mean? Ground wire in the FI harness pinched, torn, broken?
timothy_nd28
You should of had 12 volts from pin 10 to 5,,pin 10 to 16 and pin 10 to 17. Being that you don't have 12volts from 2 of the 3, indicates a faulty ground somewhere. I'm not sure if those 3 (pin 5,16,17) are the same wires that goes to the tin? The schematic just tells me that they all tie to ground. In your case, it's not. Maybe Jeff can chime in and enlighten us to where these 3 wires tie to ground.
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 05:36 PM) *

You should of had 12 volts from pin 10 to 5, pin 10 to 16 and pin 10 to 17. Being that you don't have 12volts from 2 of the 3, indicates a faulty ground somewhere. I'm not sure if those 3 (pin 5,16,17) are the same wires that goes to the tin? The schematic just tells me that they all tie to ground. In your case, it's not. Maybe Jeff can chime in and enlighten us to where these 3 wires tie to ground.



We shall see. I would expect somewhere to be IN THE HARNESS, right? I would hate to tear into my new harness, but it is seeming that is needed, or send it back and let Jeff do it. He can probably check his records and see if he put new wires in, or if not, maybe an old one broke.

Thanks.... (SO FAR anyway)

Clark
timothy_nd28
Yah, don't tear into your fresh harness. Do you have the 3 wires coming from the harness to the engine tin ground connection? If so, consider running a temp jumper from that to the negative battery terminal, then recheck to see if your voltages came back on the ECU connector
timothy_nd28
Click to view attachment

Is it possible to remove the black plastic ECU connector cover, so the wires can be exposed? If this is possible, you could jump pin 16 and 17 to ground, then try starting your car.
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 05:46 PM) *

Yah, don't tear into your fresh harness. Do you have the 3 wires coming from the harness to the engine tin ground connection? If so, consider running a temp jumper from that to the negative battery terminal, then recheck to see if your voltages came back on the ECU connector



Yes the ground wires are present and connected to the top of the engine. I'll try some jumping.

Clark
malcolm2
QUOTE(malcolm2 @ Jun 29 2013, 07:04 PM) *

QUOTE(timothy_nd28 @ Jun 29 2013, 05:46 PM) *

Yah, don't tear into your fresh harness. Do you have the 3 wires coming from the harness to the engine tin ground connection? If so, consider running a temp jumper from that to the negative battery terminal, then recheck to see if your voltages came back on the ECU connector



Yes the ground wires are present and connected to the top of the engine. I'll try some jumping.

Clark


TAKE THAT BACK. One had popped off. The new female connector on the FI harness was a bit too wide to stay on the blade. I closed the gap and installed. Then checked the voltages again and now I have 12 volts between
10 and 5,
10 and 16 and
10 and 17.

The car still did not start.
timothy_nd28
Good, but we are running out of things to check. Let's double check the continuity between pin one on the ECU plug to the neg terminal on the ignition coil. You are certain that you have spark at one of the plugs?
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 07:35 PM) *

Good, but we are running out of things to check. Let's double check the continuity between pin one on the ECU plug to the neg terminal on the ignition coil. You are certain that you have spark at one of the plugs?


Pin 1 and negative had good continuity between them.

I have checked the spark via several methods over the past 2 days. I bought a spark tester... It lit up, I cranked and a buddy ground the plug, it sparked.

Just to be sure I just pulled a plug and laid it down to ground it and watched thru the back window as I started... It also sparked: click, click click and I saw the spark jumping.

There is ZERO fuel on that plug. The injectors don't seem to be opening up. I have heard about starting cars with starting fluid in the intake. We tried that last night too, but no luck. Any other tricks to at least burn some fuel?
timothy_nd28
The car will run off ether, pull off the AFM and squirt it directly in the rubber boot. You should also verify that the injectors are not firing, by pulling one and placing it into a glass jar. It is exceedingly rare, but the ECU could be at fault here.

You have spark, and fuel pressure. You also have power going to the ECU on pin 10, and all the grounds pins 5, 16,17 fixed. We checked the continuity of all injectors and resistor pack by verifying voltage on pins 14,15,32 and 33. The CHT is present and within spec as well as the continuity of pin 1 to the ignition coil. I'm speculating that you have a bad brain unit. But before you order a new one, pull a injector and make sure it's not spraying fuel.
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 08:12 PM) *

The car will run off ether, pull off the AFM and squirt it directly in the rubber boot. You should also verify that the injectors are not firing, by pulling one and placing it into a glass jar. It is exceedingly rare, but the ECU could be at fault here.

You have spark, and fuel pressure. You also have power going to the ECU on pin 10, and all the grounds pins 5, 16,17 fixed. We checked the continuity of all injectors and resistor pack by verifying voltage on pins 14,15,32 and 33. The CHT is present and within spec as well as the continuity of pin 1 to the ignition coil. I'm speculating that you have a bad brain unit. But before you order a new one, pull a injector and make sure it's not spraying fuel.


Done, pulled an injector and NO FUEL in the cup. I'll give the spray thing a try too.

I bought a grab bag of FI stuff some time back. I needed 1 piece but the guy wanted to get rid of everything. So I have a 2nd Brain, no idea of the condition, but it is covered with TAR. I have put that in and still no start. I understand it is rare to have a bad ECU, but I figured it was even less probable to have 2 bad ones. Anyway, same result.

Guess I'll start searching for one.

You never made mention of the timing. I have not really set the timing to anything past build setting of 0TDC. I figured I could at least get something out of it. And with no fuel, I guess that is not an issue yet, thoughts?

Thanks so much for all your suggestions. If you get a wild idea, let me know, I'm open.

Clark
timothy_nd28
I have little faith with parts laying in some box. Just to make me feel better, pull a injector and insert it into a jar. Pull the ECU connector off, and with one end of the jumper tied to ground, touch the other side to either 14,15,32 or 33. One of those pins will cause that injector to fire. (ignition switch in the on position)
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 08:50 PM) *

I have little faith with parts laying in some box. Just to make me feel better, pull a injector and insert it into a jar. Pull the ECU connector off, and with one end of the jumper tied to ground, touch the other side to either 14,15,32 or 33. One of those pins will cause that injector to fire. (ignition switch in the on position)



I was hopeful, but NO SQUIRT. I did get alittle spark at each connector. I pulled #4 which I have checked continuity back to the ECU connector as 33. For kicks I did touch the other connections, 14, 15, and 32, but nothing but a small spark at the connector but no squirt.

Does this lead us to the injectors? ALL 4? I will have to check my records, but I sent them off for testing, etc... and have the document, somewhere.
timothy_nd28
How fancy is your meter, does it check dc amps? You have 30 some psi behind each injector. They should spray like holy hell when you ground them out at the ECU connector. So maybe your ECU is okay, I'm glad we did this last ditch effort type of test! lol
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 10:15 PM) *

How fancy is your meter, does it check dc amps? You have 30 some psi behind each injector. They should spray like holy hell when you ground them out at the ECU connector. So maybe your ECU is okay, I'm glad we did this last ditch effort type of test! lol


No amps on this meter. There may be one in the neighborhood to borrow. I almost snagged an amp meter from work for this weekend testing. I will go get it, if I can't round one up down the street.

Fuel pressure has dropped to about 10. Should I pump it up and try again? 10 seems like enough to test. Shouldn't I have heard a click, even if no fuel pressure was there?

Clark
timothy_nd28
Yah, you should hear a slight click, but I think the pintle shaft thingys are seized. Do you have a spare one in that box of yours?

Go ahead and pump up the system again, it shouldn't matter but the added pressure may help free the seized FI's.
malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 10:27 PM) *

Yah, you should hear a slight click, but I think the pintle shaft thingys are seized. Do you have a spare one in that box of yours?

Go ahead and pump up the system again, it shouldn't matter but the added pressure may help free the seized FI's.


Pressure up to 30 but still no squirt.

I have no extra injectors in my grab bag box of tar covered FI stuff.
timothy_nd28
Pull the injectors and send them to Witch Hunters. They will go thru them and get them un-seized.
JeffBowlsby
Hey Clark, Tim, I have only loosely followed this thread, sounds like you are going through things, with some success.

Were the injectors already 'rebuilt' and sat for awhile? If so they may be plugged...the chemcial they use to clean them can harden-up and cause them to not flow. You may be able to free them up by blipping them with a 9V battery a few times, and I would start by soaking their tips in something to help free them up - brake cleaner or acetone maybe?

To get the one L-jet car I had to run, I used one of the manuals on my site - there is a methodical approach to check all the components and systems, might help you too.

I will try to watch this thread, but if you need me, email me.

http://bowlsby.net/914/Classic/TechNotebook.htm

malcolm2
QUOTE(timothy_nd28 @ Jun 29 2013, 11:11 PM) *

Pull the injectors and send them to Witch Hunters. They will go thru them and get them un-seized.


I found my emails to Cruzinperformance.com, that's who did my injectors. I will reach out to Rich and see if he has any suggestions for me to do on my own. Jeff's post above makes some sense, it has been about 15 months since I got my injectors back. Lesson learned on letting re-done injectors sit. Not that I will need the lesson, by I can save someone some headaches. Do your injectors LAST, install the engine and drive.

I will remove the injectors today and see if I can break them free.

You never suggested what to do with the amp meter?

Thanks.
pilothyer
QUOTE(malcolm2 @ Jun 29 2013, 07:55 PM) *

I have heard about starting cars with starting fluid in the intake. We tried that last night too, but no luck. Any other tricks to at least burn some fuel?


Clark, I have been there a few times over the years with my 75 L-Jet and have found that I could always get it lit with starting fluid as long as the ignition was OK. Since you tried that already and didn't get it to run at all, I have to think you are looking at an ignition problem first of all, correct that then work on getting your injectors to squirt.
timothy_nd28
Never mind the amp meter. I'm fairly certain that your injectors are seized and is indeed the problem. I have heard stories of folks using a crock-pot filled with seafoam on a low setting for 12 hours to clean these injectors. I'm not sure how well this would work, other than pissing off the wife.

The air flow meter is very sensitive to back fires. I would advise removing this when running your car off ether.
Black22
QUOTE(pilothyer @ Jun 30 2013, 07:44 AM) *

QUOTE(malcolm2 @ Jun 29 2013, 07:55 PM) *

I have heard about starting cars with starting fluid in the intake. We tried that last night too, but no luck. Any other tricks to at least burn some fuel?


Clark, I have been there a few times over the years with my 75 L-Jet and have found that I could always get it lit with starting fluid as long as the ignition was OK. Since you tried that already and didn't get it to run at all, I have to think you are looking at an ignition problem first of all.



agree.gif

Although Tim knows his L-jet (he walked me through my troubles as well), if it didn't fire with starting fluid, something else is wrong.

Mine would not fire without starting fluid and it ended up being a fuel delivery problem. Check that your fuel lines are properly routed. Do yourself a favor and double check even if you are positive you did it right the first time. If its not properly hooked up from the pump and back, you will see fuel pressure, but the fuel pressure regulator can not run in reverse and therefore will not work.

There is definitely an ignition failure somewhere if it didn't fire with starting fluid though.

Good luck on the adventure.
malcolm2
QUOTE(Black22 @ Jun 30 2013, 11:06 AM) *

QUOTE(pilothyer @ Jun 30 2013, 07:44 AM) *

QUOTE(malcolm2 @ Jun 29 2013, 07:55 PM) *

I have heard about starting cars with starting fluid in the intake. We tried that last night too, but no luck. Any other tricks to at least burn some fuel?


Clark, I have been there a few times over the years with my 75 L-Jet and have found that I could always get it lit with starting fluid as long as the ignition was OK. Since you tried that already and didn't get it to run at all, I have to think you are looking at an ignition problem first of all.



agree.gif

Although Tim knows his L-jet (he walked me through my troubles as well), if it didn't fire with starting fluid, something else is wrong.

Mine would not fire without starting fluid and it ended up being a fuel delivery problem. Check that your fuel lines are properly routed. Do yourself a favor and double check even if you are positive you did it right the first time. If its not properly hooked up from the pump and back, you will see fuel pressure, but the fuel pressure regulator can not run in reverse and therefore will not work.

There is definitely an ignition failure somewhere if it didn't fire with starting fluid though.

Good luck on the adventure.


My starting fluid try was only a half hearted adventure and we did it with the air box on....I will try with the box off. 2 people had warned about the back-fire thing, so AFM off the car will protect it. I have the injectors out now, so starting fluid will be an afternoon thing.

Thanks,

Clark
malcolm2
Soaking the injectors and using a 9v battery did not help. Rich at CruzinPerformance even suggested that I tap the sides with a screwdriver. No DIY trick is going to work. They are the outfit that tested and cleaned up the injectors about 15 months ago, and he has suggested that I send them back to him and he will get them flowing for me. That is on the plate for today's UPS run.
jim_hoyland
Is there a method for storing injectors that are going to sit ? I have had several sets of 1.8 injectors that Rich cleaned and tested; probably 5 years ago
malcolm2
QUOTE(jim_hoyland @ Jul 1 2013, 02:03 PM) *

Is there a method for storing injectors that are going to sit ? I have had several sets of 1.8 injectors that Rich cleaned and tested; probably 5 years ago


Do share!

I won't need it, 'cause when he sends them back they are going straight on and the key will be turned once again. I feel success is days away.
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