[1371engineer]

hey everyone, im not much of a mechanic but im pretty positive my anti theft is cutting off my fuel pump, i recently replaced the fuel pump( brand new OE) and it keeps shutting down after driving for a few miles, theres no vacuum leak and the relay is brand new.

any help?

thanks

1998 4 door 1.8l kick jx sport
dark blue.

 

[fordem]

For starters - what "anti theft" do you have - and why do you feel it's cutting off the fuel pump?

As far as I know, the 1.8 Sidekicks weren't fitted with any "anti theft" devices capable of immobilizing the vehicle from the factory, and if I were to assume that I was mistaken on that, the factory immobilizers don't normally work that way.

Do you have any dash lights on or flashing at startup?

 

[Bex]

And how have you confirmed that it's actually the fuel pump cutting off, as opposed to a spark or ignition problem?? You may want to describe exactly what the car does as it shuts down and how it runs normally. A slow stall, or more like someone just shut off the key?
Also, is your check engine light on with the key on and off once the car is running? Do you have a scanner? If you drive with the scanner connected, you may be able to see if the ECU is showing some fault as the car shuts down, to determine whether the problem is mechanical or electronic.

 

[1371engineer]

educated guess

It was a guestimate that the fuel pump was being shut off by a security feature since I replaced the pump, I ran a power line from the pump to the fuse panel under the dash on a fuseable link and it hasnt shut off yet. When it did shut off, it was just like cranking the key off. Very sudden, any tips on why it works when I bypass the power supply,

The anti theft in question is located behind and to the left side of glovebox, its almost like a remote entry system? It is a suzuki part.
remember my main problem was stalling during driving any speed around 3-4 miles in distance.


If anyone would care to email me on the matter I'd be much obliged. I love my kick and need her running back to normal quickly or I'll have to chose between keeping her or keeping my wife haha

[email protected]

Semper fi.

 

[fordem]

I have two options here - ask you to re-read my previous post or cut & paste it.

As far as I know, the Sidekick Sport was a North American market vehicle, released to market at a point in time when Suzuki was not fitting immobilizers to vehicles for that market, and the immobilizers traditionally used did not immobilize by shutting down the fuel pump.

We can assume that you have an optional Suzuki "anti theft" device which would probably be more of a remote lock alarm type device, or we can assume that you have a third party "anti theft" device that does shut down the fuel pump (not much of a deterrent since you have apparently already figured out how to bypass it) - the point here being that making assumptions gets you no closer to identifying the problem and that's the first step into resolving it.

Stalling at any speed after driving a few miles could have any number of causes, lack of spark, loss of power on the ignition system, lack of fuel, loss of power on the fuel pump or injectors, loss of input from crank/cam sensors, defective ECU, and the list goes on.

Does it restart easily when it stalls? If not, that's where & when the troubleshooting starts - check for spark, check for fuel.

By the way - IF you do have an OE Suzuki immobilizer and it is shutting the engine down, I'd expect the dash lights to tell you that - hence my question on the lights.

 

[1371engineer]

It starts easy after the stall but dies quicker. No dash lights appear ive had my father In law look at It hes a mechanic for 22yrs and thinks theres a disruption to the power system? Im having a really tough time locating a schematic, any ideas? My kick starts fine, no low idle or sluggish accelerator, drives normaly and then just dies. Ive replaced the fuse in the engine conpartment and the relay. If I could fond a schematic for the 1.8 system itd help alot.

 

[1371engineer]

And im positive its the fuel pump that stops working.

 

[fordem]

Let me ask this question - what makes you SO SURE it's the fuel pump?

If the fuel pump stops, the engine will stop very shortly after - it's an EFI system and the pressure in the lines will be depleted within a matter of seconds (carbed engines will run a little longer until the float bowl empties), but, in both cases, if the fuel pump has stopped, the engine will not restart immediately.

Try wiring a small lamp in parallel with fuel pump and position it within your line of sight whilst driving - it will have to be where you can see it easily because the ECU will stop the pump after the engine dies - a fuel pressure gauge is another way to determine if the pump has anything to do with the problem - the system usually retains pressure after the engine is stopped, so if you have no pressure it'll be because the pump stopped.

Service information for the Sport can be hard to find - I've attached the only diagram I have.

 

[1371engineer]

Well like I said earlier, if I bypass the normal power supply and plug a fusable link from the pump to the underdash fuse board the pump will work just fine and the truck wont stall, idk if its the actual pump or if something is disrupting the power supply, I cant leave the rigged power wire In place because the pump will continue to pump and not shut off once pressurized.

 

[Rhinoman]

I would rip out the alarm/immo and reconnect the wires as they originally were. Faulty alarms seem to be getting very common, probably because they are reaching the end of their design life.

 

[Bex]

It would seem logical, then, if the car runs properly with new wiring, that your original problem is either with the original wiring or the fuel pump relay. Have you tried replacing the relay?

 

[1371engineer]

I replaced the relay, its just weird to me that it shuts off after driving for a while?

 

[aquanaut20]

I replaced the relay, its just weird to me that it shuts off after driving for a while?

1371 Marine Corps Combat Engineer

Not so, it may shut off due to heat...

Suggest you connect test light to the power wire at the pump and monitor if it is the power failing, if yes, monitor at the relay output...

..... Philip

 

[Bex]

The ECU will also cut fuel delivery, if it believes that there is no spark, as a safety precaution. If you have rewired the pump to run directly from new wiring, bypassing the ECU/relay, etc., this safety measure won't happen, which may indicate why your car continues to run when you have bypassed the relay. Just a thought.

 

[Rhinoman]

Have you traced the wiring for the alarm? some of these have a circuit breaker fitted in the fuel pump wire.