Need Help...No Start
07-04-2008, 09:59 AM
#1
Registered User
Thread Starter
Join Date: Sep 2006
Location: Newfoundland, Canada
Posts: 391
Need Help...No Start
ok, i recently built a 383 and dropped into my 93 Bird. I fired it up before putting on the waterpump and filling the cooling system to make sure the MSD distributor and wires were all firing...Everything fired up perfectly the first turn of the key. I then installed the waterpump, rad and cooling parts etc. I fired up the car to bleed the cooling system and had it idling quite nicely for about 20 min...I then shut off the car and now it won't fire up...I have spark from the coil, and i can hear the fuel pump priming...I am suspecting a bad checkvalve in the Walbro pump but it has been like this for a while. I cranked it for a short period of time and still no go...i pulled a couple of plugs and they were black with soot and very dry...the whole insulator and tip were completely black and i could wipe off the soot. It seems like my injectors aren't firing...i also noticed that the fans were on constantly when the key was ahead and that was because of an engine code but when i cross the A-B terminals in the ALDL connector it will not even blink 12 code...to allow access to check the other codes....Sorry for the long post but i'm getting fustrated....
07-06-2008, 07:40 PM
#3
Registered User
Thread Starter
Join Date: Sep 2006
Location: Newfoundland, Canada
Posts: 391
ok, i have spark...i have air and the fuel pump is priming but i checked the pressure and im only seeing 20psi at the rail...is it possible that the fuel pump is on its way out and 20 psi is not enough to start this d#$% thing???? I tried another distributor, another coil and another ignition control module and it still wouldn't start...
07-06-2008, 09:24 PM
#7
Registered User
Join Date: Oct 2001
Location: Engineerland
Posts: 1,517
Should prime to 40+ and hold there for quite a long time without bleeding off. It wont start because its too lean to fire up cold with the low fuel pressure. Prime the fuel pump 4-5 times or so by cycling the key and then try to fire it. It'll probably fire for just a bit and maybe stay running. I'd say you either need to swap filters or its time for a fuel pump. Check your fuel pressure regulator vacuum line for fuel also its possible the diaphram could be failed.
I'm not sure about on your older model stuff, but on the later models there is a fuel pump jumper under the hood. Usualy on the pass side by the shock tower bolts. It'll just be a little red wire with a plastic end on it. You could try jumpering it and making the pump run constantly. See if you get pressure that way, and then see if it falls off of the fuel pressure reg and filter check out.
I would not drive the car until you get the pressure figured out.
I'm not sure about on your older model stuff, but on the later models there is a fuel pump jumper under the hood. Usualy on the pass side by the shock tower bolts. It'll just be a little red wire with a plastic end on it. You could try jumpering it and making the pump run constantly. See if you get pressure that way, and then see if it falls off of the fuel pressure reg and filter check out.
I would not drive the car until you get the pressure figured out.
07-06-2008, 09:26 PM
#8
Registered User
Join Date: Jun 2008
Posts: 81
Technically, the dist. sends crank positon and cam position info to the computer. The computer takes that info and trigger the injectors by grounding each one for a short period of time to fire them. If one or several of the injectors are shorting, it will stop the drivers in the computer from working. Unplug all the injectors and Ohm test each one seperatly. You have eight, if most of them are say, 12ohms and one is 7ohms, you have a problem. The lower the reading, the worse it is. If you've got one that's low, hook the others back up and try to start on seven cylinders.
The only thing that doesn't add up is the computer won't give you any flashes when you short the ALDL. Are you sure the computer is powering up?
The only thing that doesn't add up is the computer won't give you any flashes when you short the ALDL. Are you sure the computer is powering up?
07-06-2008, 09:28 PM
#9
Registered User
Thread Starter
Join Date: Sep 2006
Location: Newfoundland, Canada
Posts: 391
Should prime to 40+ and hold there for quite a long time without bleeding off. It wont start because its too lean to fire up cold with the low fuel pressure. Prime the fuel pump 4-5 times or so by cycling the key and then try to fire it. It'll probably fire for just a bit and maybe stay running. I'd say you either need to swap filters or its time for a fuel pump. Check your fuel pressure regulator vacuum line for fuel also its possible the diaphram could be failed.
I'm not sure about on your older model stuff, but on the later models there is a fuel pump jumper under the hood. Usualy on the pass side by the shock tower bolts. It'll just be a little red wire with a plastic end on it. You could try jumpering it and making the pump run constantly. See if you get pressure that way, and then see if it falls off of the fuel pressure reg and filter check out.
I would not drive the car until you get the pressure figured out.
I'm not sure about on your older model stuff, but on the later models there is a fuel pump jumper under the hood. Usualy on the pass side by the shock tower bolts. It'll just be a little red wire with a plastic end on it. You could try jumpering it and making the pump run constantly. See if you get pressure that way, and then see if it falls off of the fuel pressure reg and filter check out.
I would not drive the car until you get the pressure figured out.
07-06-2008, 09:32 PM
#10
Registered User
Thread Starter
Join Date: Sep 2006
Location: Newfoundland, Canada
Posts: 391
Technically, the dist. sends crank positon and cam position info to the computer. The computer takes that info and trigger the injectors by grounding each one for a short period of time to fire them. If one or several of the injectors are shorting, it will stop the drivers in the computer from working. Unplug all the injectors and Ohm test each one seperatly. You have eight, if most of them are say, 12ohms and one is 7ohms, you have a problem. The lower the reading, the worse it is. If you've got one that's low, hook the others back up and try to start on seven cylinders.
The only thing that doesn't add up is the computer won't give you any flashes when you short the ALDL. Are you sure the computer is powering up?
The only thing that doesn't add up is the computer won't give you any flashes when you short the ALDL. Are you sure the computer is powering up?
07-06-2008, 11:24 PM
#11
Registered User
Join Date: Jun 2008
Posts: 81
If your getting fuel pump prime then the computer should be turning on. I didn't think about that. Fuel pressure is way low and probably has a lot to do with the starting problem. If you can verify injector pulse with a noid light, that takes care of are the injectors firing?
You can try some carb spray to make sure it will run if it gets fuel. If it starts up, you know for sure that your problem is fuel supply/pressure.
You can try some carb spray to make sure it will run if it gets fuel. If it starts up, you know for sure that your problem is fuel supply/pressure.
07-07-2008, 12:22 AM
#12
Registered User
Join Date: Jun 2002
Location: Akron, OH
Posts: 391
yep, spray it into your TB...it will most likely run/sputter for a few secs and then die out.. i would say either your FP or filter is the problem...how old are they?
07-07-2008, 07:41 PM
#14
Registered User
Join Date: Jun 2008
Posts: 81
Code 41 Ignition control circuit open
http://shbox.com/1/95_ign_system_schematic.jpg
Here's a 95 schematic. Hopefully the same as 93. The #11 underhood fuse is what supplies power. Check fuse and power. Terminal "C" Black is the ground. Test with an Ohm meter to see if your getting a good ground. Also, there's a ground connection on one of the studs that the ICM is mounted to. It wouldn't suprise me that it's the ground for the ICM. Take a good look at that, make sure they are all hooked up. There's a black, two brown, and a braided strap.
http://shbox.com/1/95_ign_system_schematic.jpg
Here's a 95 schematic. Hopefully the same as 93. The #11 underhood fuse is what supplies power. Check fuse and power. Terminal "C" Black is the ground. Test with an Ohm meter to see if your getting a good ground. Also, there's a ground connection on one of the studs that the ICM is mounted to. It wouldn't suprise me that it's the ground for the ICM. Take a good look at that, make sure they are all hooked up. There's a black, two brown, and a braided strap.
07-08-2008, 12:45 PM
#15
Registered User
Thread Starter
Join Date: Sep 2006
Location: Newfoundland, Canada
Posts: 391
Ok, I checked the fuse and it is good and has power. I dont's see anything grounded to the coil bracket though....the ground stud on the driverside of the block has the 2 brown wires and a black wire attached to it and the ground strap is grounded to the frame rail.