New motor won't start

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I have a 90 bronco with a 351w. I had rebuilt. I have everythung installed the new motor and it's not wanting to start not even try. But the lights and horn work. But the radio doesn't work. I can jump the starter relay but I don't want the first start up that way. I have everythung replaced all fuses and relays. I have power to the starter relay but when I turn the key it goes from 11.8 volts to .02. Have had the starter checked and battery both good. Any help will be appreciated.

 
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Just an update. I put a volt meter to the starter wire on the starter relay and ground when cranking I got .05 volts.

 

miesk5

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Yo B,

The headlights receive battery power from a fusible link, so the battery and it's grounds are OK.

I assume you are testing the red/light blue wire on the relay with the push on terminal pulled; positive red meter lead on it and black negative lead on the good ground.

Is the fender mounted relay attached to inner fender securely on a clean surface?

The relay is grounded through its "body".

Test for battery voltage from Ignition switch through mNeutral Safety Switch (automatic transmission or clutch switch for manual) to starter relay.

Here is the wiring diagram

http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=17412

Ignition Switch Pin-Out Diagram & Continuity Testing (Logic Tables in 87-91 (from Factory Manual and the Ford Electrical & Vacuum Troubleshooting Manual (EVTM)

Source: by Broncobill78 (Dave) @

http://www.fullsizebronco.com/forum/41-broncos-sale-75-posts-required-post/96024-1990-fsbronco-hallmark-pop-up-camper.html

 
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So I found a dirty green connecter. Cleaned it and the motor will now crank but will not start. I can smell fuel and I took two spark plugs out and they both were firing. I believed I time the thing right. But some times when I stop cranking it sounds like one of the spark plugs are continuing to fire inside the block. I replaced the eec relay and fuel pump relay. The distributor is brand new. I notice my old injector harness has a ground on the back that the new one does not. But the motor is grounded on the bottom and on the top to the fire wall. Any help here will be appreciated.

 

miesk5

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New update. I checked the fuel injectors with a node. I got no light when I crank the motor. Replaced the engine harness with other one. Still no power to the fuel injectors. Any ideas?

 

miesk5

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Yo,

OK.

As far as the old harness ground, I do not see a seperate ground to frame, body, or other point. Each injector's ground to operate it is done individually in the PCM through the tan & wHite wires at each Injector.

How do you know it is a ground; does it have an oval terminal?

Try this Fuel Injector Test (5.0L Engine, 5.8L Engine) @ http://troubleshootmyvehicle.com/ford/4.9L-5.0L-5.8L/how-to-test-the-fuel-injectors-1

by Abraham Torres

Then;

Inspect the wiring harness to the injectors and at the PCM.

The injector is normally closed. It is operated by 12V VPWR from the EEC-IV Power Relay and the ground signal is controlled by the Powertrain Control Module (PCM). This is the Red wire to each connector.

Wiring diagrams:

http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=11304

Follow path to injectors (RED) from Ignition switch THROUGH EEC POWER RELAY THROUGH splices to each injector. It is labeled circuit 361 on page 2

Note: Do not apply battery voltage directly to the injector electrical connector terminals. The solenoid may be damaged internally in a matter of seconds. Try grounding the Tan and White wires @ the injectors.

If spark was present in all of the cylinders:

ignition control module is OK

PIP is OK.

coil is OK.

Here is the EEC IV PIN Connector Diagram

http://web.archive.org/web/20120115055623im_/http://www.oldfuelinjection.com/images/eec04.gif

And the PIN LEGEND

http://web.archive.org/web/20120118104425/http://www.oldfuelinjection.com/truckpinouts.html

Both by Ryan M

All resistance tests should be done with the ignition key in the off position. Having voltage going through the system can return a false reading of excessive resistance. Additionally, it is possible to have a ground that tests OK when the engine is cold, but not when the engine is hot. Heat increases resistance, so these tests should be performed on a warm engine when possible.

To test for an adequate ground circuit in the EFI system, use a Volt/Ohm meter to check the resistance of the

following circuits. Disconnect PCM Connector:

• To verify a proper ground to the PCM, check the resistance from pins 20, 40 and pin 60 DIRECTLY to the negative side of the battery. Of course, battery ground cables, connector, and grounds must be clean and tight.Resistance should be no greater than 0.2 ohms.

•Replace faulty wiring between computer and battery if not.

 
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There was a blown capacitor in the computer. Replaced computer and now it runs great. Loss of power replacing brakes tomorrow

 
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new topic now. my motor is bogging down when i accelerate even a little bit hard. replaced all brakes and calipers. still happening. the exhaust is making a crazy noise when i am driving and hitting the throttle but not when i'm in park and rev the motor no sound from the exhaust. cutting it off tomorrow any other ideas would be helpful. new motor is running great in park and i have the timing set around 7 or 8 BTDC. that is what the guy who built the motor told me would work best with the new cam.  

 

miesk5

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Yo,

It is better to start a new thread for a different topic.

For now:

Bogging;

Vacuum leak, see my leak diagnosis in post #20 @

http://broncozone.com/topic/23994-90-58l-getting-continuous-code-33-and-running-code-44/?p=125535

Air filter, is it relatively clean?

Air inlet atop radiator support to filter box and to throttle body; look for obstruction; damaged tubing, etc.

Fuel quality; Oxidized fuel often turns darker over time and may even smell sour. You can check stored gasoline by pouring some into a clear glass container and comparing it side-by-side with known fresh gasoline. If your old sample looks noticeably darker than the fresh gas, you have strong evidence the gas has gone bad.

Look for a loose connector especially those with broken locking tabs.

...

Any chance there is a misfire? If so, check spark plug Wire routing.

....

Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19 @ http://broncozone.com/topic/14269-code-reader/?pid=74587&mode=threaded

 

Elmo

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you didn't say,  therefore I have to ask. The 7-8 BTDC set point for the timing.... you did this with the spout connector OUT correct ? 

 
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Yes the timing was set to 8 BTDC. With the spout disconnected. But I got a new engine harness and new pcm. It runs great now.

 

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