Engine will crank but won't start unless you spray starter fluid in it



Okay so I have a 2004 Dodge Ram Hemi, the truck was running fine all this weekend and was fine this morning. Went out at lunch and used the automatic starter button while walking to it and wouldn’t start. It turn over and wants to start you can hear it trying to catch but it won’t catch unless you put some starter fluid in. Just changed all 16 spark plugs, all 8 coil packs, wires and 2 vavlesprings about 2 weeks ago have been running fine since and now this. Any ideas on what it could be?


Check to see if the fuel pump starts is the first thing to do. If not is there power to the pump.


Yep, you have a fuel problem. However, that could be caused by a number of things. A quick first test is to swap the fuel pump relay in the power control module under the hood with another with another in the PCM with the same part number.


The next time the engine won’t start, turn the ignition switch to run so the dash lights come on for two seconds, and then turn the ignition switch off.

Repeat this a half dozen times and then try starting the engine.

If the engine starts right up, the problem is with the anti drain-back valve on the fuel pump assembly.



After you put some starter fluid in the throttle body intake, does it start and run ok indefinitely then? Until the next time you try to start it cold? Or does it start, runs for a few seconds, then immediately sputters out?


It’s sputters out unless you give it gas and stay in the gas if not it dies


We switched that out and it didn’t do anything.


So if I understand, it will run and drive ok (like nothing was wrong) as long as you keep pressing on the gas pedal enough to prevent a stall? But if you let off the gas pedal, it quickly stalls & dies?

hmm … I’m thinking the throttle position sensor. Have you checked that?


See the problem is if we spray in starter fluid you can get it to catch but have to sit there and give it gas can’t even move it or take it out of park cause if you let off the gas it dies


My husband just said he check the fuel pump the lines for it are completely dry. But I have a half a tank of gas.


Then the problem is most likely with the electronic throttle body.


Instead of a throttle cable to the throttle body, the throttle body is electronically controlled by the computer. And the idle is controlled by the computer.

Sometimes cleaning these electronic throttle body’s will fix an idle problem, and other times the throttle body requires replacement.



The gas line can’t be completely dry, otherwise it wouldn’t run at all. You say it will run as long as you are pressimn on the gas pedal. I think Tester (above) is probably right. That’s where to check first anyway, imo. If that brings no joy, a fuel pressure test is probably next.

Edit: If you feel lucky, it cold be the fuel pressure regulator too. Not sure if your truck uses one though. But if it does, and it is part of a fuel return system which returns unneeded fuel rail fuel back to the tank, ask your mechanic to remove the vacuum hose connected to it (which goes to the intake manifold) and check for any fuel inside. There shouldn’t be any.


He did a fuel pressure test and it didnt spray out it kinda just dribbled a little fuel out


A fuel pressure test doesn’t involve spraying any fuel. It’s done with a precision pressure gauge.


There’s something wrong with the fuel pump.

If you cycle the ignition switch just one time, the fuel pump should pressurize the fuel system in a second or two, and fuel should spray out the Schrader valve.



I think he was just pressing down the shrader valve to see how much pressure was there and not actually putting a tester on it.