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I have a 2008 Accent that just died while driving the other day. When we plugged in the scan tool it told us the cam positioning sensor was bad. So, we replaced it. After that it still will not start up. I'm thinking that there is an issue with the fuel pump. I flipped the seat up, took the cover off the expose the tank so I could listen. When I turn the key to the on position the pump only buzzes for a few seconds and it doesn't kick on every time. So, i disconnected the line from the rail and fuel isn't pushed out until cranking the engine. seeing as fuel sprays out I'm not sure if this is normal. Am i right to think the fuel pump is shot? or is it an issue that could have been caused by a bad CPS?
 

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Drives : Nissan NV200 Flies : Rans S6ES
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Have you checked that the spark plugs are firing when you crank the engine? Also check to see if there is power being supplied to the fuel pump DURING CRANK.
No spark and no power supply to the fuel pump are often symptoms of a faulty crank position sensor.
 

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2007 Honda CRV
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When first turning the key to the "ON" position, the fuel pump should turn on for a couple of seconds and then off
This is priming the fuel rail. Then with the engine cranking, the fuel pump should be on all the time.

What is the mileage on the vehicle?
When was the timing belt last changed?
Take the oil fill cap off the valve cover and shine a light into there
Have a friend crank the engine while you watch the valves
Do they move? If yes then good so far
If no movement then belt may be broken??

If it isn't the belt then try checking for spark at the plugs
And check also for injector pulse. This can be done sometimes by laying fingers on the injector to feel for injectors firing.
Or you can use a test light or DVOM (digital volt ohm meter) to check the circuit.

Good luck
 

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why not just remove upper plastic timing cover it's like 5 10 mm bolts? see if belts snapped- if snapped your options are valve job (cause atleast a few are bent) and head surface checking/ piston crowns or new used engine- sounds like the belt let go - oh and fuel pump- normal operation it primes when you turn key to on postion engine off- but if it's sending bad signals for pcm for firing order may be causing pump to shut off i'd check belt first cause if it let go theres no point going further
 

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2008 Accent 3 dr 5 sp manual; 2010 Genesis Coupe 2LT track 6 sp manual
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You can get rebuilt head on line or eBay. Get that and a head gasket kit, timing belt kit, and look at the crank pulley for cracks.
 

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Drives : Nissan NV200 Flies : Rans S6ES
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Yeah, get all that and it still doesn't start 'cause the crank sensor has failed :surprise:
 

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Pop the top, and visual the timing belt for break or fouling.. rotate crank to DTC by hand and verify crank TDC with timing dot of cam cog to mark on head..

2008, suspect broken belt,, people not real maintain minded with them little car.. IF it is broken, flip an new timing belt on it enough that you can try to start engine (make sure crank pulley secure in place to keep belt from walk off when it start),,,, see how it run

If it seem to run & idle fine, assemble the covers and stuff back in place and go for drive.. easier than up and goofing with head and what not..
 

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2008 Accent 3 dr 5 sp manual; 2010 Genesis Coupe 2LT track 6 sp manual
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Yeah, get all that and it still doesn't start 'cause the crank sensor has failed :surprise:
He said the fuel pump sprayed out the open line when cranking, no crank sensor no fuel pump I believe. But I don't know his excat procedure he used.
 

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Actually, perhaps what the OP described is consistent with a broken timing belt. He said he scanned for DTCs and found a camshaft position sensor fault. He change it and it didn't fix the problem.

If the timing belt broke, the camshaft wouldn't spin while cranking so the cam sensor wouldn't send a signal to the ECM, triggering a fault (... the OP never clarified if the DTC came back after changing the sensor). Assuming the crankshaft position sensor is good, it would still be sending a signal to the ECM while cranking the engine so perhaps this is why he has output to the fuel pump (i.e. fuel "spraying" out of the fuel line). As others have suggested, he should take the top timing belt cover off and inspect the belt since it's very easy to do.

I looked in the service manual and I can't find anything that says the ECM would cut power to the fuel pump if the crank sensor fails, but it does say that the crank sensor controls both ignition timing and fuel injector pulse width while the cam sensor is used (along with the crank sensor) to control ignition timing. One thing that's confusing is that in one place it says the crank sensor determines the position of each piston while the cam sensor determines TDC for each cylinder and in other places it says the opposite. I would think the cam sensor is determining TDC just by looking at the long square wave forms in the manual, but perhaps someone can verify which is correct?

Anyway, the OP never returned to update or answer questions posed by others.
 

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2008 Accent 3 dr 5 sp manual; 2010 Genesis Coupe 2LT track 6 sp manual
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As I understand the fuel pump logic....


When you turn the key to on and then start you are booting the ECU program. The fuel pump should by default run for some timed value. If the crank sensor does not then see any movement the pump is not again turned on. There may be a pressure sensor that is also in the works but it would not be active until the ECU was booted by the start sequence.
 
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