ranger no spark
#1
ranger no spark
I have a 86 ranger, 2.3L manual. died while driving. replaced fuel pump and relay, later discovered that there was no power to the pump. discovered no spark situation. ICM and coil tested ok. Ground ok . replaced ignition switch. still no spark. Possibly EEC computer? out of desperation, I tried for spark without the Computer installed. Got lots of spark, but still no power to the fuel pump. This is a stumper. any help appreciated. thanks, Mike.
#2
It possibly is the computer. But I do not have enough experience to confirm. Please look at this tread: https://www.fordforum.com/forum/ford...t-start-31083/
there it ended up being the computer. Testing circuits seems to be the key.
there it ended up being the computer. Testing circuits seems to be the key.
#3
Mike,
Your vehicle should have a relay ,EEC relay, that provides power to the fuel pump relay and the computer.
Do you own a simple test lite? Both the EEC and fuel pump relays should have power available to them through terminal 30 on each relay. That circuit is protected by fuses.
With the test lite check your fuses first, then confirm power is available at both #30 terminals of those relays. When you turn the key on you should hear/feel the EEC relay and the fuel pump relay click on. The fuel pump relay will operate for only 2 seconds if the computer receives no RPM signal. What do you have so far?
Your vehicle should have a relay ,EEC relay, that provides power to the fuel pump relay and the computer.
Do you own a simple test lite? Both the EEC and fuel pump relays should have power available to them through terminal 30 on each relay. That circuit is protected by fuses.
With the test lite check your fuses first, then confirm power is available at both #30 terminals of those relays. When you turn the key on you should hear/feel the EEC relay and the fuel pump relay click on. The fuel pump relay will operate for only 2 seconds if the computer receives no RPM signal. What do you have so far?
#4
Also, your vehicle has 2 fuel pumps. A low pressure in the tank and a high pressure on the frame rail. Also, double check the small ground lead that comes off the negative battery post. That one is spliced into a 5 pimt ground that feed several items including the computer and is also for the fuel injectors.
#8
unbelievable no spark yet
Ok Hanky, I am going nuts here. The truck has a new computer, new EEC, new EEC relay, new fuel pump, new ignition switch. Coil and icm tested ok. When I turn the key on the fuel pump doesn;'t come on and there is no spark. The icm has been tested also. If I remove the EEC completely, spark comes back but still no power to fuel pump. I even wired past the inertia switch. At my wits end here, may be time to cut my losses! cant help but think that there is still a simple common denominator that I am missing. engine turns over fine. Just weird.
#9
I've been there, nuts I mean, it was a short trip for me !
You need to stop just replacing parts , it's gonna get very expensive.
Let's tackle this slowly one at a time. This is simple stuff on an older vehicle using a test lite.
When you turn the key on you should have power to the coil, do you?
If yes, good. If no , power comes from the ign switch to the coli when the key is turned on. Which do you have?
Power comes from a 60 amp fuse in the engine compartment and goes to the ign switch. (yel wire)
When you turn the key on power goes from the switch through a Red/LtGrn wire to the coil primary, and to the PCM -EEC power relay to cause it to close and turn on. Do you hear/feel the relay click when you turn the key on?
You need to stop just replacing parts , it's gonna get very expensive.
Let's tackle this slowly one at a time. This is simple stuff on an older vehicle using a test lite.
When you turn the key on you should have power to the coil, do you?
If yes, good. If no , power comes from the ign switch to the coli when the key is turned on. Which do you have?
Power comes from a 60 amp fuse in the engine compartment and goes to the ign switch. (yel wire)
When you turn the key on power goes from the switch through a Red/LtGrn wire to the coil primary, and to the PCM -EEC power relay to cause it to close and turn on. Do you hear/feel the relay click when you turn the key on?
Last edited by hanky; 02-07-2014 at 05:38 PM.