- Joined
- Jun 2, 2012
- Messages
- 25,363
- Reaction score
- 8,370
- Points
- 113
- Location
- canada
- Vehicle Year
- 1994
- Make / Model
- Ford
- Transmission
- Manual
So the no fire, no start after adding fuel manually is new, to me anyway, lol.
So yes Spark would have to be the first stop, the 2.9l uses a timing CHAIN so compression is not likely the problem.
Get a Test light, just a 12volt light bulb in a easy to use holder
It has a clip on Ground wire and then you just touch probe to connector to see if bulb lights up, very easy to use.
Bulb itself IS A FUSE so no danger of shorting anything out
No Spark is an electrical issue, which is why you need something to tell you if you are getting electricity to Spark system
Clip the test light wire to any metal engine part, or Battery Negative if wire is long enough.
Then touch Probe to battery positive, test light should light up brightly, this is just to test if it is working, I have wasted time using a bad test light before, lol, so I test them each time I will be using them
They are $10-$20, the longer the wire on the test light the better.
Turn on the key
There are 6 fuel injectors, 2 wires each, locate the easiest one to see and touch probe to either wires connector, you should be able to push probe down into the top of the connector on injector.
You should have 12volts there, test light lights up
If not, and key is on, then the EEC Fuse or EEC relay is bad so no power to injectors OR Spark system.
There is one connection between transmission and Spark system, thats the START wire.
On the transmission is the NSS(neutral safety switch), it is located on drivers side just above shifter linkage.
When you turn the Key to START 12volts is sent thru this switch to the Starter Relay on the inner fender and this activates the Starter Motor to crank the engine.
And this is working, the wire between NSS and starter relay....................but there may also be a splice in this wire or two wires on the same connector at the NSS switch.
This second wire runs to the START contact on the TFI module.
Why the second power wire to TFI module?
In the past automakers ran the spark system at 8 or 9 volts, not the 13-14volts that is available when engine is running, this made the points and coils last longer, this was done with a Ballast Resistor or Resistor Wire between ignition switch in RUN and the Spark system.
But to start a COLD engine it is better to have full available voltage for spark.
So in the IGNITION SWITCH there were two pathways to the Spark system
In RUN position the 12volts ran thru ballast resistor to the spark system
In START position the 12v ran directly to spark system, full voltage.
In START position the RUN voltage to spark system is cut off, and visa versa
It was a common issue in the past where engine would start and then die as soon as key moved from START to RUN, a failed ballast resistor, so spark worked in START but power was cut in RUN.
Newer ignition switches don't have this, newer spark systems don't need the ballast resistors, so spark system just gets 12volts in either START or RUN positions
Ford had LOTS of these older style ignition switches, lol, so they used them up, by adding a wire that would provide 12volts to spark system when key was in the START position, the splice to the Starter relay activation wire.
If this wire were damaged then Spark system would have no power while engine was cranking but would in RUN position, so a No Start but all voltages would check out as OK with Key On, RUN position.
Only way to diagnose this is to test START wire at TFI module while someone cranks engine over USING THE KEY
OR..............
Turn key on, RUN position
And jump Starter Relay, activate starter motor without using the key, if TFI has voltage then engine would fire
TFI wiring seen here: http://www.therangerstation.com/how-to/ignition-charging-computers/ford-eec-ivtfi-iv-electronic-engine-control-troubleshooting/
So yes Spark would have to be the first stop, the 2.9l uses a timing CHAIN so compression is not likely the problem.
Get a Test light, just a 12volt light bulb in a easy to use holder
It has a clip on Ground wire and then you just touch probe to connector to see if bulb lights up, very easy to use.
Bulb itself IS A FUSE so no danger of shorting anything out
No Spark is an electrical issue, which is why you need something to tell you if you are getting electricity to Spark system
Clip the test light wire to any metal engine part, or Battery Negative if wire is long enough.
Then touch Probe to battery positive, test light should light up brightly, this is just to test if it is working, I have wasted time using a bad test light before, lol, so I test them each time I will be using them
They are $10-$20, the longer the wire on the test light the better.
Turn on the key
There are 6 fuel injectors, 2 wires each, locate the easiest one to see and touch probe to either wires connector, you should be able to push probe down into the top of the connector on injector.
You should have 12volts there, test light lights up
If not, and key is on, then the EEC Fuse or EEC relay is bad so no power to injectors OR Spark system.
There is one connection between transmission and Spark system, thats the START wire.
On the transmission is the NSS(neutral safety switch), it is located on drivers side just above shifter linkage.
When you turn the Key to START 12volts is sent thru this switch to the Starter Relay on the inner fender and this activates the Starter Motor to crank the engine.
And this is working, the wire between NSS and starter relay....................but there may also be a splice in this wire or two wires on the same connector at the NSS switch.
This second wire runs to the START contact on the TFI module.
Why the second power wire to TFI module?
In the past automakers ran the spark system at 8 or 9 volts, not the 13-14volts that is available when engine is running, this made the points and coils last longer, this was done with a Ballast Resistor or Resistor Wire between ignition switch in RUN and the Spark system.
But to start a COLD engine it is better to have full available voltage for spark.
So in the IGNITION SWITCH there were two pathways to the Spark system
In RUN position the 12volts ran thru ballast resistor to the spark system
In START position the 12v ran directly to spark system, full voltage.
In START position the RUN voltage to spark system is cut off, and visa versa
It was a common issue in the past where engine would start and then die as soon as key moved from START to RUN, a failed ballast resistor, so spark worked in START but power was cut in RUN.
Newer ignition switches don't have this, newer spark systems don't need the ballast resistors, so spark system just gets 12volts in either START or RUN positions
Ford had LOTS of these older style ignition switches, lol, so they used them up, by adding a wire that would provide 12volts to spark system when key was in the START position, the splice to the Starter relay activation wire.
If this wire were damaged then Spark system would have no power while engine was cranking but would in RUN position, so a No Start but all voltages would check out as OK with Key On, RUN position.
Only way to diagnose this is to test START wire at TFI module while someone cranks engine over USING THE KEY
OR..............
Turn key on, RUN position
And jump Starter Relay, activate starter motor without using the key, if TFI has voltage then engine would fire
TFI wiring seen here: http://www.therangerstation.com/how-to/ignition-charging-computers/ford-eec-ivtfi-iv-electronic-engine-control-troubleshooting/
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