Hello, my problem is aggravating me.. I went out to warm up my truck, was 10 degrees outside, it started fine and ran for about 3 minutes and then died, i went to restart and it just cranked. I checked the fuel at the relief, lots of pressure, pulled the plugs and checked for spark, have spark at all plugs but still won't fire. Fuel pump has hum when I turn ignition. Check engine light is on when I turn on, but goes away when I start to turn over engine. Is it the EEC?, looked over my chilton but cannot locate relay, anyone have a suggestion...

 

Are you saying that the fuel pumps are running all the time with the key on and the engine not running?
If so then yes it does not sound good for the EEC Computer.



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no the pumps don't run all the time, you get the initial hum when I turn the ignition on, but then cuts off like it suppose too after 1 to 2 seconds, I have good pressure on the fuel rail and good spark, just won't start..

 

try starting fluid.

sounds like eec is ok.

 

Is it flooded?
If so hold the throttle on the floor while cranking.

Is the battery low?
If the PIP voltage is low it can be enough to fire the coil but too low for the PCM and the PCM will not fire the injectors.

 

Not a real mechanic, but I have tried starting fluid by opening the airbox and then spraying into the intake, still won't fire. I was wondering , since the Chilton I am using doesn't explain it very well, what controls the power to the injectors?, since I am getting fuel in the rail at good pressure, does the EEC control the power to feed the injectors to spray fuel into the cylinders?.

 

Have good voltage, new battery installed last month and showing 13 volts, but still no start. Engine isn't flooded, and have tried holding throttle down but still nothing.

 

The power to the injectors comes byway of a red wire from the PCM Power Relay. This is common to all injectors so the red wire on all of the injectors should have power on them all the time the key is on.

To fire the injector the PCM Computer then grounds the wire coming from the injector to the PCM Computer.

The PCM Computer will fire the injectors when it sees a PIP train and the PIP train must be above a certain voltage and this voltage is higher then what is required for the ICM Module to fire the Ignition Coil.

 

I tried putting a charger on the battery, keeping good voltage, now my check engine light is staying on, but same symptoms, will not start. any suggestions? would the PCM computer going out cause this?..

 

If it won't run on starting fluid and you are sure you have spark, you need air and compression. Could you have possibly broke a timing chain? How does it sound when cranking? Spin real fast? Pull your dist. cap and make sure the rotor is turning.

 

Woops! I was thinking of the wrong vehicle. Cancel the last statement, you can't have spark if the the rotor aint turnin.......DUH!!!

 

My guess is that you have a fuel problem. You may very well have the pumps running for one second and pressure at the fuel rail but the pressure may not be high enough to start and run an engine. You need to check it with a gauge with pin #6 of the test connector grounded and the key on.

Can you pull the codes now and see if you have any, if you can not pull codes it may very well be the PCM Computer.

 

agreed, but wouldn't it have fired with starting fluid?

 

Yes it should have fired with starting fluid if you have spark with or without a good PCM Computer.

I do not know where he checked the spark, if it was at the coil wire he could have a broken rotor (bug) in the distributor also.

 

thats what i was thinking on the starting fluid.

he said he had spark at all plugs.

waiting for subford to hit a home run on this one.