Fuel pump doesn't click, engine cranks with no fire (Explorer)

lemonshindig · 03-11-2009, 03:05 PM

I'm going to look at an explorer with 130k on it that I'm told needs a new fuel pump. He said that the engine cranks just fine but doesn't fire, and that you can't hear a click when you turn the key to on.

I found this Link which says that the fuel pump relay could be sticking and it may start if i fondle it.

It seems to be somewhat of a common problem from what I see online. Anyone care to shed light on this? Ever heard of it?

What do you think my odds are that it's a relay instead of the pump?

Sounds like if the relay is stuck open then there will be no drain on the battery?

Thanks
-Matt

HoosierBuddy · 03-11-2009, 03:29 PM

I can't help you with your troubleshooting, but I've seen many cars over the years listed for sale with "needs new fuel pump".

I always take it as code to mean "This thing doesn't run and I don't have ANY FRICKEN IDEA what it needs, but I think you should pay me top dollar for this thing, because it MIGHT be something simple."

Honestly, if all it needed was a fuel pump, why on earth wouldn't they fix it so they could sell it as a running/driving vehicle. It's just an Alarm Bell to me.

Phil

lemonshindig · 03-11-2009, 03:34 PM

Hehe. That may be possible.

I'm going to take a test light with me. There's 3 wires coming out of the plug on the relay switch. I figure I'll just test them with the key off and test them all with the key on. If there's no change then I know the relay's bad, correct? (I'm assuming the relay is always closed when the key is on)

Thanks
-Matt

lemonshindig · 03-11-2009, 03:35 PM

And they're not exactly asking top dollar. They want $700. If the body and interior are in good shape it's probably a fair price.

HoosierBuddy · 03-11-2009, 03:55 PM

On my 5.0's...the pump kicks on for about 3 seconds on key-on then shuts back off until you start the engine.

Phil

ductman · 03-11-2009, 06:57 PM

There is a good chance the inertia switch has been tripped. Even a minor bump from the rear or front can shut it down. This is to keep the electric fuel pump from running so the motor will shut off after an accident. Most of them are located in the rear area where the jack sets behind the panel on the drivers side. I believe that is where mine is on the 98 that I have. Mine has over 230k on it and still runs great and is my daily driver. I have a book that covers several years if you need some info let me know.

Ductman

HoosierBuddy · 03-11-2009, 07:19 PM

I don't think it will crank if the intertia switch is tripped.

Phil

egnorant · 03-11-2009, 08:18 PM

Having bought 2 cars with bad fuel systems that were really just the inertia switch, I can say that it will crank, just no fuel flow.
The click is probably the relay activating.

Have a buddy listen for a whine from the tank when you turn the key on without cranking.
Should whine for a few seconds then stop.

Bruce

ductman · 03-11-2009, 08:21 PM

The engine will crank but the fuel pump will not get power thru the relays. In the past I have also bypassed the relay to get the pump to work. A paper clip works well for a temporary fix.

Ductman

John_Del · 03-11-2009, 10:02 PM

Quote:

Originally Posted by HoosierBuddy

Honestly, if all it needed was a fuel pump, why on earth wouldn't they fix it so they could sell it as a running/driving vehicle.

Changing a fuel pump in an EFI vehicle is beyond most driveway mechanics capabilities. It's a nasty job to do at home, and professionally done, it's like $600 to $800. I can see someone with an older, high mileage car with a bad pump just selling as is.

I love the ones with a bad skip that only needs a "tuneup".

On the OP's Explorer, I would try thwacking the tank with a rubber mallet while someone cranks the engine. About half the ones I've thumped have started temporarily.

John

lemonshindig · 03-12-2009, 01:23 AM

Inertia switch, relay, or the pump itself. Definitely sounds diagnosable but I'm not sure if I'll be able to completely figure it out while taking a look at it. I'll try bumping the relay and the pump and see what happens.

I'm looking at 2 or 3 other explorers so I'll check them all out before making a decision.

2 of them have the 5-speed transmission which I'm fairly confident would be a wise choice considering the reputation of the first gen automatics.

I really like the look of a red '92 I found on ebay but it's about 6 hours away. Maybe I'll invest in a maaco paint job if i buy under my budget.

Thanks guys
-Matt

autoxsteve · 03-12-2009, 09:39 AM

I'd bet on inertia switch. My Sister-in-law had a blowout on her Taurus and the engine died as a result of the blowout. She had it towed to my house and in 15 minutes (most of that time was digging for the user's manual) I had the car running again...

You should take a stab at that. Might be able to flip the car and make some cash if you bet on that.....

MustangBillsInc · 03-12-2009, 09:59 AM

don't forget to have a look at the fuel pump fuse, not just the relay. My ranger died on the side of the road and i couldn't figure it out on the roadside so had it towed put a new fuse in and away i went, till the fuse blew again. turned out to be the wiring harness was rubbed through and periodically grounding to the body, it finally just went to a dead short and fried the fuel pump. thats when i had the fuel pump replaced and the wiring traced.

lemonshindig · 03-12-2009, 12:55 PM

All excellent points. I'll use my test light to see if there's power at the fuel pump. If there isn't then I will look at it as a wiring/circuitry issue and assume the pump is good.

Thanks
-Matt

Lemondrop · 03-12-2009, 07:49 PM

Neither one of my Explorers ever had issues with the fuel pump relay or inertia switches. Both had fuel pump failures at around 180K miles.