Won't Start
Fleet Owner
Joined: Aug 2005
Posts: 23,667
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From: Easton,Ks
Originally Posted by manasota
No gas in the vacuum hose. Distributer is tight.
What controls the firing of the injectors?
What controls the firing of the injectors?
They are wired in banks of three with a power wire that is hot while the ignition is on from the EEC power relay and common to all injectors.
The EEC Computer grounds the other side of each bank to fire three injectors at a time, the banks are (1,2,4) and (3,5,6).
The EEC Computer will ground these banks when it sees a PIP pulse train from the TFI module and the TFI Module gets its information from the pick-up coil (AKA "PIP Sensor", AKA "Hall effect vane switch assembly", AKA "Stator")
So if the injectors are not firing (you can hear them they are very noise, photo below) then you have one of the following things wrong.
Distributor not turning.
Stator in the distributor.
TFI Module.
Wiring and Plugs.
EEC Computer.
The above is taking in to the account that you do have fuel pressure and if you have fuel pressure you have power from the EEC Power Relay.
Last edited by subford; May 30, 2007 at 08:58 AM.
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OK...I'm not getting anywhere on this. guess it's time to replace some parts and see where that gets me.
Let me summarize:
1. Fuel pressure is about 38-40 lbs. and holds fairly steady. I can hear both pumps engaging when I turn the key.
2. It's getting spark.
3. Spark plugs don't appear wet, just sooty.
4. No sign of gas in any of the vacuum lines.
5. I think I can hear the injectors when I turn the ignition to to the run position, but I can't be certain.
6. No blown fuses, bare or broken wires that I can see.
I'm going to replace the TFI first (about $40).
Let me summarize:
1. Fuel pressure is about 38-40 lbs. and holds fairly steady. I can hear both pumps engaging when I turn the key.
2. It's getting spark.
3. Spark plugs don't appear wet, just sooty.
4. No sign of gas in any of the vacuum lines.
5. I think I can hear the injectors when I turn the ignition to to the run position, but I can't be certain.
6. No blown fuses, bare or broken wires that I can see.
I'm going to replace the TFI first (about $40).
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