 Is there any way to tell if my L-jet brain is dead without swapping it |
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| jd74914 |
 Apr 18 2007, 10:47 AM
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Its alive  Group: Members Posts: 4,850 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States  |
Hi guys, heres the problem.
A few months ago my car was running great. I had just rebuilt the engine and put everything back on. After fixing some grounding problems it ran perfectly. Then, I went on vacation, came back and did some welding and forgot to unhook the brain when I unhooked the battery. After this the car wouldn't start. It wasn't getting any fuel. The coil also got really warm at one point, so I replaced it with another known good, new one I had. Now with the new coil, and a new fuel pump (I also had a known good pump) put in, the car still won't start. It turns over fine, but it won't even run for a second on the cold start valve (IMG:style_emoticons/default/sad.gif) Is there a problem with the brain or is there something else I should look for? I can't think of any other things to go bad. (IMG:style_emoticons/default/idea.gif) I'm pretty sure the points are good. Its a 74 L-Jet BTW |
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| r_towle |
Apr 18 2007, 12:14 PM
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Custom Member Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States 
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remove the big ass Air flow meter valve from the large intake rubber hose.
turn the key to the run postion, no jumpers on the fuel pump, just have it wired correctly. gently slide your finger in the Air flow meter and move the plastic flapper door with your finger... When you move the door just a bit open, the fuel pump will turn on. These cars are kinda wierd to start with no fuel in the lines. This is how I had to "prime" the system. The fuel pump will not come on under normal conditions until the motor is running and sucking enough air to move that door open... So, you replaced the fuel pump, yet there is not enough fuel pressure in the lines to get the car started to open the door to get the fuel pump running...its a catch 22. When you run the pump, listen and you will hear the tone of the pump change and lower down because its under load. When it does that, the fuel system is now pressurized, and the car should start. If your stuck, I have two unknown Ljet brains you can borrow to test.. Rich |
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Posts in this topic
jd74914 Is there any way to tell if my L-jet brain is dead without swapping it Apr 18 2007, 10:47 AM
jimkelly guess you gotta check for spark, is fuel pump comi... Apr 18 2007, 11:11 AM jd74914 The pump isn't coming on at all. Thats what ha... Apr 18 2007, 11:39 AM jd74914 Ok, Thanks for that thought Rich.
I'll try pr... Apr 18 2007, 02:10 PM Dave_Darling The pump should also run when the starter is crank... Apr 18 2007, 02:50 PM
jd74914
The pump should also run when the starter is cran... Apr 18 2007, 02:58 PM SLITS The single yellow wire to your starter is from you... Apr 18 2007, 03:18 PM ChrisNPDrider I just went through this with D-jet and the soluti... Apr 18 2007, 03:32 PM bd1308 that yellow wire goes to the bottom RIGHT pin on t... Apr 18 2007, 03:36 PM jd74914 Bottom right is i'm looking from the battery t... Apr 18 2007, 03:41 PM bd1308 trunk Apr 18 2007, 04:04 PM jd74914 mine was always plugged into the left thanks Apr 18 2007, 04:06 PM computers4kids
mine was always plugged into the left thanks
Mi... Apr 18 2007, 07:55 PM bd1308 if you stood behind the trunk and was looking at t... Apr 18 2007, 08:08 PM computers4kids
if you stood behind the trunk and was looking at ... Apr 18 2007, 08:12 PM bd1308 alright here's what you need to do:
After the... Apr 18 2007, 08:29 PM ClayPerrine
The Ignition turns the IGN relay on the relay bo... Apr 18 2007, 09:53 PM jd74914 I think I have heard the clicks . . . I'll che... Apr 18 2007, 09:50 PM |
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