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Matt, Engineer
Category: Ford
Satisfied Customers: 21984
Experience:  BEng hons Mech engineering, in auto industry 22 years
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Engine stall dnt kn why ? it ended up throwing timing chain

Customer Question

engine stall dnt kn why ? it ended up throwing timing chain we took heads off to see if bent any valves none was bent but rings was shot we replaced now engine cranks slow and wont start battery good starter is new do you have any idea what would cause 2004 f150 5.4l 3v triton
Submitted: 2 years ago via
Category: Ford
Expert:  Matt replied 2 years ago.
I'd go back to basics a bit
1st check for spark by removing one of the spark plugs and plug it back into its lead and rest it on the metal of the engine ( DO NOT hold it on place by hand) then have your assistant turn the engine over whilst you watch the plug. It should give a fat blue spark at regular intervals.
If not then check that there's power to the coil pack (at the other end of the plug lead) using a meter. If there’s 12V at the pack but no spark then check the ECU power supply (fuse and relay) and also the connections to the crankshaft speed sensor.
If there is a spark and its still not starting then its likely that the ECU isn't opening the fuel injectors, if the injectors are working you can hear them click - its difficult to hear them with background noise so use a long screwdriver like a stethoscope, placing the handle end in your ear and the metal tip against the body of the injector whilst your assistant turns the engine over.
If you can't hear anything check the ECU power is present by measuring voltage at the fusebox and on its relay socket if OK then check the connections to the crank speed sensor and consider replacing this sensor if the wiring / connections look OK
If the car will start using a squirt of quick/ easi start into the intake then this confirms the problem is lack of fuel
Also its worth checking that the electric pump that feeds the injectors is working correctly, it should run for a few seconds then switch off when you first turn the ignition on. If you remove the filler cap to the fuel tank and listen inside while your assistant flicks the ignition you should hear it clearly
If the connections to this are corroded or damaged then the pump could stop at any time. Check that its relay switches in and out and the relay contacts are clean and bright – replace the relay if in any doubt and do the same for the fuse, ideally measure the voltage at the pump and check its getting 12V.
You should be getting around 3 bar measured at the injector rail check to see if the plugs are getting wet indicating fuel is flowing – if not and the injectors are opening then there’s a problem with the pump or the filter or even the pressure regulator
Could also be incorrect fuelling due to a faulty water temp sensor. If this is the problem then the ECU will never add the 'cold start' extra fuel required if the car starts OK when warm then I 'd look into changing the sensor.
Customer: replied 2 years ago.
it was stalling out before we put timing failed but the oil was burnt inside engine so i thought that helped the timing to go out . after we redone the rings and timing the motor wont turn over fast to start engine volts drop at battery to 6 and should b 9 . what would cause the slow crank and drop
Customer: replied 2 years ago.
and also how can i clean the codes off computer it reads multibel codes
Expert:  Matt replied 2 years ago.
thanks for the extra infromation
I'd 1st investigate the fuel pump as thats the bet fit for the issue
Also to clear the codes ideally use a diagnostic device but you can do it crudely by removing both battery leads and clamping them together for 10 mins as this will reset everything so if the light re-appears then the fault is still there.
Disconnect the battery cables and clamp them together for 10 mins. Remove both battery leads from the battery then use a nut and bolt or G-clamp to hold both battery lead terminals together.
This discharges any capacitors / memory within the ECU and around the car so ensures all memory settings are wiped clear - back to the factory default.
This will reset all the systems on the car and you may need the radio security code to get it going again, and ensure that the keys are in your hand when you re-connect the battery as the car may lock and turn on the alarm
Customer: replied 2 years ago.
i have checked fuel pump we have pressure on fuel rail i have not checked the spark but we should not have a spark because of while cranking the motor the volts drop to 6
Expert:  Matt replied 2 years ago.
OK thats a pretty low voltage and as you say this will create all sorts of issues with starting
I'd 1st check that main earth connections are tight and un-corroded and also check the smaller earth connections that run out of the main engine wiring loom and are secured to the engine with ring terminals
If this is all OK tehn I'd consider replacing the battery
Customer: replied 2 years ago.
we have checked wiring by eye and with meter also 3 batterys have been put on we even ran extra grounds could the timing be off or a camphaser be retarded and cause motor to drag
Expert:  Matt replied 2 years ago.
The cam timing should have been set with the phaser 'locked' so the timing is set with the phaser at its end stops
if the phaser is out of position then it can be moving around during cranking which would certainly hurt starting
Sounds like the next step will be to have the cam cover off and re-do the cam timign ensuring the cma phaser is locked up
Expert:  Matt replied 2 years ago.
do you still need help?