start problem

trucker433

Registered User
Iwent to work parked come back out 8 hours later car cranks but wont start changed out ignition contol module and coil pack still no start . Pushed the shrader valve while cranking no fuel so I jumpered fuel pump at relay in trunk pump comes on fuel shoots up to hood when press shrader valve. Had buddy spray starting fluid in throttle body car starts. My car is 90 and automatic The upshift light is not in the tack gauge it is on the bottom by check engine light. It is on while cranking and does not go off. Does the crankshaft sensor hold out the fuel pump as well as fuel injectors
 
Two options I can come up with
1) Fuel rail clogged

2) PCM failed

Is there pressure maintained on the system? What is the pressure when the inertial relay is bypassed.

Actually sound like either the pump or the Relay is bad, did you try and start care with relay bypassed?
 
Yes I tryed to start when relay bypassed it has plenty of pressure when bypassed. I had read in other thread that the crankshaft sensor controls pulse for injectors I was wondering if it also controled fuel pump start.
 
Well to test to see if injectors are firing either back probe one of them with a Voltmeter or plug a Noid light into one.

To my knowledge the FP is not controlled by the crank sensor.
 
thanks im going to check in a little while i also going to check the ignition switch i read on other post it sometimes cracks an causes problems
 
If the upshift light does not go off while cranking, that typically points to the crank sensor being the problem.

If no signal from the crank sensor, then no activity from the injectors as that signal controls injector timing. It has nothing to do with the fuel pump.

Fraser
 
If the upshift light does not go off while cranking, that typically points to the crank sensor being the problem.
If no signal from the crank sensor, then no activity from the injectors as that signal controls injector timing. It has nothing to do with the fuel pump.

heh I'm with the above.. BUT if the EEC doesn't sense a signal from the crank sensor (?), it will not turn on the fuel pump.. it needs a signal saying that the engine is indeed turning (at a spec speed?) to command the fuel pump to turn on..

With that being said..
Do you here the fuel pump turn on when you turn the key to the run position ONLY for a couple of seconds??
If you cycle the key two or three times, do you have fuel pressure at the Schrader Valve??
 
My 89 is doing the same thing. I can jumper the fuel pump relay, spray starter fluid in the intake, and it'll crank up and run. If I remove the fuel pump jumper it stalls as soon as I open the throttle body or when the fuel rail depressurizes. The crank sensor can definitely be bad on mine, too. It makes sense as to why the fuel pump won't run by itself.
 
I see what yall are saying but I just don't see the fuel pump and Crank Sensor on the diagrams, expect for pin 8 on the PCM

Ford said:
Fuel Injectors, mounted in the intake manifold at the intake port, meter the flow of fuel into the engine. The PCM fires the injectors separately.

Fuel is supplied to the engine by an in-tank Fuel Pump. When the Ignition Switch is turned to the RUN position, the PCM grounds the Fuel Pump Relay for 1 to 2 seconds. The PCM also grounds the Fuel Pump Relay as long as it receives a Profile Ignition Pickup (PIP) signal from the Ignition Control Module.

When the Fuel Pump Relay is grounded by the PCM and the Inertia Fuel Shutoff Switch is closed, power is supplied to the Fuel Pump. Fuel flow is produced by the Fuel Pump, and fuel pressure is built up in the fuel system. Fuel pressure is controlled by a fuel pressure regulator.

Easy way to check Crank (PIP) is to check A/C voltage on pin #4 and ground of the ICM looking for ~5V A/C while cranking.

Looked closer at the service manual and you either have a ignition ground (replace ICM) issue or the crank sensor is bad. Would have never guessed it actually controlled the fuel pump.
 
Both the Crank sensor and Cam sensor Send a separate signal to the EEC and DIS module via separate wires coming from the sensors.. are they bridged inside the sensor i do not know but by the wiring they are separate..

Also another way to force the Fuel pump on is to ground the Tan w/ Green? Wire at the self test connect when the ignition switch is on..

But still..
If the Fuel pump doesn't turn on for around 2 seconds once the key is turn on to the Run position.. I would ground the above Tan wire, If the fuel pump Still doesn't turn on.. Check the fuse, wiring, relay.. If it turns on.. Check the wiring, grounds, and power for the ECU.. Else i would think BAD ECU??

To say the output driver for the ECU could of gone bad, wouldn't be too far fetch thou.. Transistors can only last for so long, add in the age and deterioration of the wiring, connectors and relay over that time.. that load on that transistor would increase, possible pass it's limits?
 
Yes the fuel pump comes on for 2 seconds when key turned on does build pressure but while cranking nothing and upshift light on
 
Then for you, i would suggest replacing the Crank sensor and/or check over the wiring too it

Also make sure the harmonic Balancer is good too
 
after climbing underneath and pulling cover for sensor harmonic balancer just spins and wobbles where do you get new pulley assy not alot of money
 
they're not cheap, sadly, unless you get used, and even then you are drawing straws as to how long THAT one will last..

I know Supercoupe Performance has the BHJ ones, at like under $400 :eek: but they are suppose to the of the quality that you'll never have to worry about it failing ever again..

One day i need to get under my SC again and check mine..
 
Dorman has a aftermarket balancer assembly with crank pulley for $260 plus shipping out of www.rockauto.com. The BHJ unit is likely a higher quality unit, but does not come with a pulley and requires you to get a zero balanced pulley or have your pulley bolted to the balancer and and the assembly zero balanced by a machine shop.
 
nope---I'd venture a guess that there as many missing as there are that have them.........................Dan
 
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