Ford Repair Questions? Ask a Mechanic for Answers ASAP
I would like to help you diagnose this problem you are having with your vehicle.
Do you have a voltmeter?
Does the check engine light come on with the key in the on position?
Lets check one thing at a time.
Just hang in there with me.
Turn the key to the on position (don.t start the engine). Does the check engine light come on?
Ok... I just wanted to know if it comes on with the key in the on position.
Lets check for a 5 volt reference with the key on at the tps sensor.
Do you know where the tps sensor is?
It will be located on the throttle body assembly. It will have three wires going to it.
Let me know if you need pictures.
I am pretty sure I have found it,green ,black and orange wires running to it .Does the key switch need to be on?
One of those wires should have 5 volts on it
You said that we do not have spark.... correct?
DO we have power at the ignition coil?
Ok.... but no ground signal trigger?
To check the ground signal trigger, you are going to want to use a test light. The clip or alligator side of the test light gets hooked to battery power. The tip of the test light touches the signal wire to the coil. WIth the engine cranking over, the test light should blink if the coil is receiving a signal to fire spark.
No time limit... take your time!
I will be on line all day tomorrow!
Here is a wiring diagram.
I believe you have a wiring or low voltage issue. This can be caused by a bad/loose connection or something like that.
If you would like to approach it by going after the fuel pump relay and inputs, lets do so.
I would be willing to bet you are right... it is going to be something simple. We just need to find it.
If you are willing to stick with me, I will have you run a series of test so that we can pinpoint this problem. It may take a bit, but I am willing to do this if you are too.
At this point I am ready for anything!!
I am going to ask some silly and basic questions. Just stick with me as I will not leave you hanging. I am in the middle of dinner but I will try my best to respond to you asap!
Ok.. that is just fine.
First step is to go to the fuel pump relay and check all the wires.
Can you get me the color wires that go into this relay?
The yellow and the red wire should both have FULL battery voltage with the key on. I want to check for voltage on both of these wires with the key on and the relay still plugged in and clicking. we are going to need to back probe these cavities to get a voltage reading because we are going to leave the fuel pump relay plugged in.
After we do this test I want to see if the voltage changes on either of these two wires with the relay unplugged.
Just as a side note, I came across this TSB that I thought that I should bring to your attention.
Engine/Ignition - No Start Condition
87ford20NO START - EEC IV - "E" COILArticle No. 87-20-18FORD: 1983-86 LTD 1983-87 ESCORT, EXP, MUSTANG, THUNDERBIRD, CROWN VICTORIA 1984-87 TEMPO 1986-87 TAURUS
LINCOLN-MERCURY: 1983 LN7 1983-86 MARQUIS 1983-87 LYNX, COUGAR, GRAND MARQUIS, MARK VII, CONTINENTAL, LINCOLN TOWN CAR 1984-87 TOPAZ 1986-87 SABLE
LIGHT TRUCK: 1983-87 RANGER, E-SERIES, F-SERIES, BRONCO 1984-87 BRONCO II 1986-87 AEROSTAR This article is being republished in its entirety to expand the model year coverage.
ISSUE: The primary winding of the E-core ignition coil may be damaged if the wire harness containing the tachometer circuit has a short to ground. ACTION: Before replacing the E-core ignition coil, perform the following diagnostic procedure. 1. Turn ignition to "ON" position. 2. Measure and record battery voltage. Figure 50 3. Measure and record voltage between negative terminal and coil and battery ground post as shown, Figure 50. 4. If the differencce in readings is greater than 1.0 volt, check tachometer circuit for a potential short to ground. 5. If a short is present, make necessary wire harness repair. 6. Replace ignition coil as required. OTHER APPLICABLE ARTICLES: Supersedes 84-14-18, 84-14-18-S, 85-16-13, 86-2-21 WARRANTY STATUS: "INFORMATION ONLY"
Here is a wiring diagram for your fuel pump relay.
If we have low voltage coming into the fuel pump relay on the red wire, lest go back and check the EEC relay and inputs.
If we have low voltage coming into the fuel pump relay on the yellow wire, lets go back and check the "blue" 20 gauge fusible link.