Fuel Pump Disable

[JD1964]

I want to crank the engine but have the fuel pump off. What's the easiest way to temporarily disable the pump?

I'd like to avoid triggering a CEL if at all possible.

 

[elarm1]

flip that trigger in the trunk

 

[JD1964]

flip that trigger in the trunk

It's a hatchback. Is the switch behind the back panel somewhere?

 

[elarm1]

Yes, its located behind back panel, left of the trunk lock. Trip it and it will disable the pump. Why are you doing this?

 

[JD1964]

Yes, its located behind back panel, left of the trunk lock. Trip it and it will disable the pump. Why are you doing this?

Before I put the spark plugs in (so the engine will spin faster) I just want to spin it a bit to make absolutely sure the roller rockers clear the modified baffle in the valve cover.

I'll align the cover with two bolts just a few threads in. Then, while my helper cranks I'll hold the cover down and feel/listen for clearance problems.

That's my plan anyway.

 

[elarm1]

Just disconnect the coil wire and fire away! No unscrewing or solonoids to trip

Edit... It doesn't have any plugs in. so whats the problem here? Just start the car with the gas pedal to the floor

 

[JD1964]

Just disconnect the coil wire and fire away! No unscrewing or solonoids to trip

Edit... It doesn't have any plugs in. so whats the problem here? Just start the car with the gas pedal to the floor

Fuel line won't be connected at the point of the test. If I turn the key on with fuel line unhooked, gas will gush all over.

 

[elarm1]

then plug it back up then floor the gas pedal when starting

 

[JD1964]

then plug it back up then floor the gas pedal when starting

Flooring the pedal won't matter. The upper intake is not on yet.

 

[JD1964]

I like your suggestion of the solonoid in the back. I'll do that. Thanks.

 

[stykthyn]

Flooring the gas pedal while cranking tells the injectors not to pulse. Either hook up the line and floor the gas pedal or trip the inertia switch. Honestly I would just spin it by hand with a wrench. If there is contact you will hear it.

 

[JD1964]

Thanks again to both of you. I didn't know flooring the pedal prevents injectors from pulsing.

Are most other fuel injected cars like this too?

 

[elarm1]

Flooring the gas pedal while cranking tells the injectors not to pulse. Either hook up the line and floor the gas pedal or trip the inertia switch. Honestly I would just spin it by hand with a wrench. If there is contact you will hear it.

Probably the safer method as less destruction would occur if something was screwed up

 

[stykthyn]

Option 3 wild be to bridge the starter solenoid on the fender with a screwdriver. This will merely bump the starter and not prime the fuel system.

 

[88LX5.Oh]

^ that's what I'd do. Don't have to take any panels off inside the car or anything. Just jump the solenoid, the small top pin to the big pin with the red wire going to it. Simple as that lol

 

[7991LXnSHO]

I do not know your year, but reach under the driver's seat and unplug the fuel pump relay.

 

[JD1964]

Option 3 wild be to bridge the starter solenoid on the fender with a screwdriver. This will merely bump the starter and not prime the fuel system.

Sounds like the ticket. Good idea.

Not only does it not energize the pump, but the ignition stays dead too, correct?

 

[Grabbin' Asphalt]

Jumping the solenoid is easy to do, be careful using a large diameter screwdriver, the amp load can melt the contacts inside. You can use a small screwdriver or wire, both works fine.

 

[jrichker]

How to crank engine without ignition or fuel pump being powered on.
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