1989 Ford E350 will not start, possible EEC Problem
 

I purchased a 1989 Ford Motorhome on a E350 chassis. It has a 460 engine and will not start. Found and fixed the following, fusible link at starter motor relay was blown, broken wire in back of motorhome, have traced all wires from batteries to fuel pump, and replaced both batteries. Unit will crank but will not start. Checked the following, EEC relay, has strong snap, fuel pump relay, no snap when key is turned on, but as a stand alone test, the relay pulls in strongly.

Have checked that fuel pumps run. Now am suspicious that blown fusible link with connection to pin 1 of EEC may have blown unit. The reason is that the voltage at the fuel pump relay is only about 4.0 volts when tested in place. Can anyone confirm suspicions or give me some other items to check?

All help at this point is welcome. Thank you.

I have the same exact problem with a 1987 Ford E350 chassis motorhome that previous owner let sit in a barn for four years. Cranks and fires on starter spray but won't run. Cannot tell if electric fuel pump in the rear tank is working. Diagram shows a tip-over safety relay in cab passenger side by the heater motor but tests show it appears to be working. If anybody posts a solution to this problem, I would love to know the answer also.
jh

Have ya'll both tried jumping the fuel pump relays manually, and attempting engine start at the same time? If the ECM connection to the fuel pump relay is broken somewhere when you turn the key the ECM will power up but the pumps won't so trucks won't start, but if you've already energized the pumps manually then it won't matter if the ECM has connection to them or not - trucks should run.

You both need to check to see if the injectors are firing when the engine is cranked.
You will have power on one side of all the injectors with the key on and the other side should flash the noid light while cranking.
You can rent a noid light set at O'Reilly auto parts stores and maybe others.
Do not use an meter while testing non computer wiring, only use a test light that loads the circuit or you will chase your tail all day long. You will find that the 4.0 Volts above is more than likely zero volts with a test light.
Make sure that the RED wire leaving the EEC Power relay has 12 Volts on it with the key on and the small black wire with a green stripe leaving the NEG (-) post of the battery has a good ground.

If:
1. The Red wire has power.
2. The noid light is not flashing while cranking.
3. With a good ground at pins 40 & 60 of the computer.
4. An you have good power at pins 1, 37 & 57 of the computer.
5. You have good spark.
6. Cranks and fires on starter spray but won't run.

then you may have a bad computer.

1989 Ford E350 will not start, possible EEC Problem
 

M.L.S.C. and Subford,

First, thank you for both of your replies. I have a bit of time into this diagnostic at this point and it can be frustrating. So I appreciate your comments and leads.

Second, I plan to try your suggestions. Unfortunately, yesterday I did not get a chance to work on the unit. I shall try these ideas today, hopefully, and give you an update.

Thank you again and I shall let you know what I find.

aland

1989 Ford E350 will not start, possible EEC Problem
 

To Subford,

I checked all the following, and I think I need to change the EEC. All checked as indicated and I still do not have power to the fuel pumps.

If:
1. The Red wire has power.
2. The noid light is not flashing while cranking.
3. With a good ground at pins 40 & 60 of the computer.
4. An you have good power at pins 1, 37 & 57 of the computer.
5. You have good spark.
6. Cranks and fires on starter spray but won't run.

I am going to try the EEC route and let you know.

aland

If u have checked the relay check the relay connector for the eec. Does the check engine come on when u turn the key on? If the wiring to the eec relay is broken the fuelpump wont run and u will not have any check engine light when u have the key in the on position. My problematic wire was a red one with a fusable link over in the eec relay.

1989 Ford E350 will not start, EEC problem
 

Hi deeznuts822,

Thank you for the reply. I shall check this again, but during my initial analysis, this was all right. Also, for this year, the Check Engine Light was only available for the manual transmission. I have an automatic.

I do appreciate the hint. Anything like this can help.

If u have fuel injection and electric fuel pumps u should have a check engine light in the dash when u turn on the key

By the way the EEC Computer has nothing to do with voltage at the EEC or Fuel pump relays. It can only ground one side of the coil of the fuel pump relay on the EEC IV, FI, OBD I system.

Also you say this is a 1989 motorhome, most (90%) of 1989 motor homes were 1988 E350 Ford incomplete chassis. I though that the 1988 E350 460 was still Carb and not FI. If so you will still have a fuel pump and other relays that make when you turn on the key but you would have a Check Engine Light (MIL).

You did not say how you did a stand alone test of the fuel pump relay.

1989 Ford E350 will not start, possible EEC Problem
 

To Deeznuts822 and Subford, and to all who read the post,

Thank you for your suggestions and comments. Before you think that I am not very bright, let me clarify a couple of points brought up by deesnuts822 and subford.

First, I have the unit running. To the question of the check engine light, there was no light lit when I started this journey. Due to my research, I thought, incorrectly, that this unit and year did not have a check engine light. This was wrong, I do have one, but whatever fried the computer did not allow for this signal to go to the light.

Second, Subford, you are correct, the EEC computer has nothing to do with the voltage at the EEC or Fuel Pump Relay. That was a pilot error on my part, and I stated it wrong.

Third, the stand alone test I did was based on a piece I found on another forum, which states to put twelve volts to the two smaller lugs on the relay and to check the resistance on the two larger lugs. When I did this, I found that the relay was good, based on this test. You may say that this test is not correct. Again, since it has been a long time since I have played with gas engines I bowe to your superior knowledge. If this had been a diesel, I would have had it running much quicker.

Fourth, I replaced the EEC, and behold the check engine light lit, the fuel pumps came alive, and the engine started. Very reassuring after all this work. I think the previous owner fried the circuitry in the EEC, as I said in my first post, I did fix the fusible link at the starter relay that supplies a lot of the circuits we have been discussing.

Last, thank you for all of your help. This forum has been very useful for me and I appreciate all of the advice.

adefreit

Where is the fusible link and starter motor relay?
 

I purchased a 1990 Ford Motorhome Fleetwood Flair on a E350 chassis. It has a 460 EFI engine, the alternator is not charging. I would like to know where is fusible link and the starter motor relay. Please help.
Thanks

Where is the fusible link and starter motor relay?
 

Hi,

As I recall the fusible link is on the passenger side. As you stand in front of the motorhome, it would be on your left.

The relay for the starter is in the same location.

Why do you think that this is the problem with charging? Usually, the problem with charging is either worn brushes in the alternator, or a bad voltage regulator which is integral on this unit, I believe.

Hope this helps.

Alan

Alan,
Thank you for your super fast reply.
My alternator doesn't charge the batteries. It looks like a tough job to replace the alternator. I want to check the fuse link first before going to replace the alternator.
Thanks again
Viet

If you have the 2G alternator most of the time it is the plug that plugs into the alternator or the fuse link has burned open.