2001 5.2L

I noticed that my engine would turn over for a few seconds before it started...or maybe I would have to turn the key back and try again before it fired up. The starter sounds great and I have full battery.

I changed the cap/rotor all the plugs and wires...thinking maybe that would help, but it is still the same. The truck runs great and super smooth, but it just takes a bit to start it up.

Anyone know why this might be? I have tried turning the key to "on" to let the fuel pump gain pull pressure for a few seconds before turning the key to start it, doesn't help. The truck does this probably about 7 out of 10 times, and is a bit worse when cold. I don't want to take life off the starter. Anyone with a similar problem?

 

whats your temp there? whats the CCA on the battery? how old is the battery?

and ive seen many trucks with this problem, not much to worry about.

 

Temp when I bought it last week...55-65 Temp today...35-60 (really no difference in performance)

Good question on the battery.... I just bought the truck with 90K miles. The battery is an OEM Mopar battery, but the dates are not circled/etched out on the battery. Don't know when it was installed. Could it be the original on a 2001? I suppose.... Maybe I should start there?

 

Mine does the same thing. I know a few others than do too... Still trying to figure it out myself!

 

my 99 does this too but my bros 01 doesnt, my ignition is all new and the battery is new too.

 

my 01 doesnt although I have had some wierd restarts. My friends 97 does the same though as you are describing.

 

Are you positive you are getting proper fuel pressure?
Sounds (to me) like the fuel pressure is a bit low....

 

no like the op stated ive even tried to turn the key to on, let the fuel pump prime for a second or two then start the truck and the same thing happens

 

I agree, it sounds like a fuel pump delivery issue and, without measuring anything, one cannot rule out a fuel pressure issue. I'm staying with a friend of mine who's got a 99 that does this and, I took a reading. Sure enough, it is low thus, why it starts and sometimes it does not - DESPITE turning KEY <ON> to prime the pump.

I highly recommend taking measurements over a period of time to "see" what the fuel pump / delivery system is actually doing vs. just assuming it's ok because, in my experience with fuel delivery systems, often enough, it's a lack of fuel pressure that causes a hard start / no start condition.

EDIT: Even when turning the KEY <ON> event, if the voltage at the FUEL PUMP connector is LOW or, there's a voltage drop anywhere in that CKT, the pump WILL NOT prime the system in ONE KEY ON event thus, requiring multiple attempts to obtain / reach the MIN operating pressure.

<IF> the FUEL PUMP regulator check valve remains OPEN, it will not hold pressure and, after KEY <ON> event, the gas flows directly back into the tank thus, inducing a hard start condition. This is also why it may be hit or miss more so vs. when there's a voltage drop in the CKT.

Now, there's a few other things that will also induce a hard start such as leaking injectors and, in order to find out what the root problem is, testing is required to rule and / or factor out each possible failure mode.

I would start with the pump pressure first. I would run five cold pressure tests on random days to gain stats over time. I would also measure the voltage at the FUEL PUMP during each test to see if there's any correlation. Let's say on one day, the pressure is ~30 PSI, if the voltage at the connector reads <12 volts, well, that's the correlation between the two and, one could safely say that, the low pressure was directly related / induced by a voltage drop at the fuel pump connector or, perhaps, at some other point in the wiring harness and / or CKT respectively.

<IF> the FUEL PUMP / PSI readings measure up (~50 psi), one can factor out the fuel pump as suspect and move on.

CM

 

Mine is doing this too. Someone once told me it could be the crank position sensor. Could that be the cause? Didn't seem to make sense to me but fuel system makes more sense.