Long crank on cold start

[sasnak]

OK, so been having this issue for a while now, and just decided to replace the Fuel pump as most people are suggesting to fix this.
Only had my 1999 TJ 6 cyl for close to a year now, so i had no idea how old the pump was. 160K on Jeep.
Replaced the pump assembly from extreme terrain this weekend. Still getting long crank. Got a fuel pressure gauge and attached to fuel rail.

COLD ENGINE. Clicked the ignition on and gauge immediately read 50 PSI. Started and pressure went to 58 PSI after long crank.
Let it sit for a couple hours and pressure down to 20psi. Turned on key and pressure when to 50 again. Then Started right up.
So bleeding off is not an issue if pump is working. Just has to get pressure back before starting. I am guessing from this experiment.
But something else is keeping it from starting when cold. If i pump the gas a couple times when cranking it starts.
IAC issue or cam position sensor?
Ideas?

 

[TJ Jim]

How long is your long crank time. I’ve only got my Jeep for a reference and I’m thinking the engine probably starts after about three seconds. That seems long to me on a fuel injection engine and compared to my other two modern cars.

 

[sasnak]

How long is your long crank time. I’ve only got my Jeep for a reference and I’m thinking the engine probably starts after about three seconds. That seems long to me on a fuel injection engine and compared to my other two modern cars.

its at least 5 seconds and usually take 2-3 times. Usually starts when i start pumping the gas

 

[macleanflood]

Have you ever replaced the injector o-rings?

Have you checked your spark plugs?

-Mac

 

[sasnak]

Have you ever replaced the injector o-rings?

Have you checked your spark plugs?

-Mac

New plugs, wires, and dist cap right after i purchased. NO on the injector o-rings.

 

[sasnak]

New plugs, wires, and dist cap right after i purchased. NO on the injector o-rings.

i need to pull a couple plugs just to see what they look like i guess also

 

[sasnak]

i need to pull a couple plugs just to see what they look like i guess also. i will look into the injector o-rings

 

[macleanflood]

New plugs, wires, and dist cap right after i purchased. NO on the injector o-rings.

What brands? Might want to read a plug or two.

-Mac

 

[sasnak]

What brands? Might want to read a plug or two.

-Mac

dont remember brands right off the top. what was recommended. i will pull plugs tommorrow

 

[TJ Jim]

So if you do the three key cycle trick does it start faster?
Turn key on and off three or four times then engage the starter.

 

[D's Jeep Wrld]

im experiencing the same and i gotta prime the fuel pump so turn the key to the "on" position then off 2 times and she starts right up
I noticed that this issue happened after i dropped the tank to do the fuel filler check valve fix when i pulled my rear axle painted the frame etc. but i digress. However i know i have some bad injectors so ill throw the fault to my injectors lol, I'll be getting some new injectors this upcoming monday and i might do it the same day but since im there im gonna do some new connectors from painless to freshen everything up

TO summarize this issue happened after dropping the tank but i know i have some bad injectors so until then ill be seeing if that's my real issue....

 

[sasnak]

So if you do the three key cycle trick does it start faster?
Turn key on and off three or four times then engage the starter.

So what i dont get is the fuel pressure issue. I have a pressure gauge connected to fuel rail. Even with the pressure at 0 as soon as i turn key on i get fuel pressure to the fuel rail 50psi. So what does it matter if it bleeds off? i am getting fuel to the injectors but still hard starting when cold. Gotta be something else i am thinking now. Once it starts its not missing or running rough. So if injector issue i would think that would be constant issue.

 

[TJ Jim]

So what I didn’t add to my example is I’m running 48psi while engine is running and mine drops pressure within minutes of shutting her down. Down to zero. So maybe the regulator is bleeding past and maybe not. I’ve got a 2020 Ram and a 2019 Audi and they light off almost immediately when I press the button. My Jeep probably turns over a couple of times before she lights off. So it’s not as fast as the newer vehicles which is why I was asking what is a long start in your opinion? If you’re comparing it to newer vehicles maybe you don’t have a problem at all. Kinda hard to quantify how long. I’m not around any other jeeps to compare starts.

 

[sasnak]

dont remember brands right off the top. what was recommended. i will pull plugs tommorrow

pulled one plug this morning and look great. no carbon, dry. just pulled the IAC and cleaned. putting back in next. Could it be the coil?

 

[TJ Jim]

Did you try the three key then start trick? If so did it start any quicker?

Can you add a video of your starting sequence so we can follow and give you a better answer?

 

[sasnak]

Did you try the three key then start trick? If so did it start any quicker?

Can you add a video of your starting sequence so we can follow and give you a better answer?

OK, i will see if i can figure that out. Next cold start i will video

 

[KennethS]

Pumping the gas on a carbureted vehicle is SOP to set the choke and spray fuel with the accelerator pump; a fuel injected vehicle has neither of those.

I am not 100% sure, but it seems pressing the gas pedal on a FI vehicle would only result in the injectors spraying fuel, as long as the fuel rail is pressurized.

 

[sasnak]

So if you do the three key cycle trick does it start faster?
Turn key on and off three or four times then engage the starter.

i have tried that and did not change anything.

Did you try the three key then start trick? If so did it start any quicker?

Can you add a video of your starting sequence so we can follow and give you a better answer?

 

[sasnak]

Pumping the gas on a carbureted vehicle is SOP to set the choke and spray fuel with the accelerator pump; a fuel injected vehicle has neither of those.

I am not 100% sure, but it seems pressing the gas pedal on a FI vehicle would only result in the injectors spraying fuel, as long as the fuel rail is pressurized.

i agree with you 100%. I don't get it either. Pressure gauge on fuel rail is 50psi. I crank the first time and sometimes when i stop cranking it tries to start.
Not always. Then the second time i crank it, if I pump the gas pedal once or twice it usually starts right up.

 

[Mall'er]

I would suspect some leaky injectors. It has to clear the excess fuel before it will start. Opening the butterfly allows more air, which will help clear the excess fuel.