Ok, I'd like to rephrase the question: Can anyone tell me the symptoms of a broken fuel pump? My car initially turns over, starts for a second, then stalls. Then after that it just turns over and doesn't start. I hear the fuel pump come on for a second as soon as the engine stops cranking.

 

<SIGH> I already told you what to check. If you want to stick to the psychic reader method, good luck to you. i am out of this pointless thread.

 

Does anyone know the symptoms of a broken fuel pump? Also, what are the components of a fuel pump system to look at when the car is not running because it's not getting gas?

 

You need to understand how the system works

1. You get in the vehicle and dock the key

2. The ECU primes the fuel line by running the fuel pump for a couple of seconds

3. The fuel pump is shut off awaiting further instructions from the ECU

4. You press the start button and the ECU commands the starter to run (assuming that you have met the criteria)

5. The ECU checks the MAF, MAP, Crankshaft and Camshaft sensors when it gets a plausible reading from all of these it turns on the fuel pump

6. If an invalid signal is received then the fuel pump never runs (beyond the initial priming) and the engine will not run for more than a few seconds


As has been pointed out the best place to look for a problem at step 5 is by checking the fault codes.

If I had your problem I would disconnect the MAF and force the ECU to use the MAP and if it runs with the MAF disconnected then look for a problem with the intake tube or with the MAF.

Good Luck

Paul

 

Ok, thanks for the information. I did run the codes and twenty codes came up which were not there before the car stalled out. I'll try the MAF method that you'd mentioned and check back with the results. Thanks.

 

The reason the the ECU operates the fuel pump in that manner is for safety... it's designed to not run unless the engine is running or cranking (other than the initial momentary prime to facilitate the start).

 

Ok I pulled the 22 error codes:
1) P0366 camshaft position sensor B bank 1
2) P0365 camshaft position sensor B bank 1
3) P2402 evap emission system leak detection pump ckt high
4) P0341 camshaft position sensor A bank 1
5) P0642 sensor reference voltage A circuit low
6) P0069 manifold absolute pressure- barometric pressure correlation
7) P0340 camshaft position sensor A bank 1
8) P0335 crankshaft position sensor A circuit
9) P0430 catylist system efficiency below threshold bank 2
10) P0340 camshaft position sensor A bank 1
11) P0365 camshaft position sensor B circuit bank 1
12) P2138 throttle pedal position sensor switch D/E voltage correlation
13) P0366 camshaft position sensor B bank 1
14) P0365 camshaft position sensor B bank 1
15) P2402 evap emission system leak detection pump control circuit high
16) P0341 camshaft position sensor A bank 1
17) P0642 Sensor reference voltage A circuit low
18) P0069 Manifold absolute pressure- barometric pressure correlation
19) P0340 camshaft position sensor A bank 1
20) P0340 camshaft position sensor A bank 1
21) P0365 camshaft position sensor B bank 1
22) P2138 throttle pedal position sensor switch D/E voltage correlation

 

I changed the all the camshaft and crankshaft position sensors a few months ago and the truck ran great, so not sure why their codes would pop up now. Also, some of the codes appear to be caused by low battery power but the battery is brand new, only a few months old.

 

You may need to look for a bad ground.

But first you need to confirm the Voltage while cranking.

If it dips too low then you may get the problems that you are having.


Here are the ground points (you can ignore the markups that I added to help someone else)




Good Luck

Paul

 

Yeah, that looks like low voltage gremlins...

This car absolutely hates a weak battery, and even a new battery can go bad, it's not that uncommon especially in this era of supply-chain issues.

Make sure you have the right battery, and it's not an el cheapo special.

Get the battery tested professionally, ie CCA. A static voltage check is not sufficient to determine if the battery will hold voltage during cranking.

Check grounds as Paul suggested. I would also check all of the big positive power cables (I think they're all red, but not certain). The ones connecting the battery, starter, and alternator.

Also... it's a possible that a tired-out starter could draw too much current. Only way to check for that would be a bench test or maybe resistance check on windings. If removed the starter I'd probably just replace it at that point, especially if it has a lot of miles (100k+).