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Discussion Starter #1
Driving down the road... Bam! Dead. Sputters but won't start. Reset the immobilizer. Checked fuel pump fuse. Wiggled the connectors on the fuel pump relay. No ECU codes thrown. Made sure there is gas (dash display is broken because of the crappy lotus connector). After turning the key I can hear the fuel pump run and never turn off.

Is there a way to test the fuel pressure without buying a whole new rail with fittings for a pressure meter?

The fuel pump fused blows every 1000 miles or so. I took it to Corey at VMG Scottsdale and he said he fixed a connection on the fuel pump but it still blew the fuse after driving for a while.

What could cause the fuel pump to run continuously?
 

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You're certain that you are hearing the fuel pump run forever and not the throttle actuator? Sorry to ask a kind of insulting question, but it wouldn't be the first time that a diagnosis went astray because someone heard that.
 

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Discussion Starter #3
Thanks kfennel! I think you're right. The buzzing sounds much louder near the engine than near the fuel pump.

I'm still unsure how to test if I'm getting fuel through though. Can I remove the injectors and see if they are squirting?

As for testing if the fuel pump is working... I took the seats out and I'm looking at the top of the pump... I see several wires but I don't know which is which and what to hook the multimeter into.
 

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Discussion Starter #4
Ok so I didn't do anything except wiggle some of the wires around the fuel pump. Now I can definitely hear the fuel pump running! The only problem is that it never shuts off! I let it go for over a minute and it's very loud. When I crank the engine it just sputters and I can hear the fuel pump shut off, but as soon as I stop cranking the pump comes right back on again... Indefinitely. So I'm back to the original problem...
 

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Without codes its gonna be hard to say... you can pull the plugs and verify fuel comes out when you crank? I would maybe start with that one cyl at a time and see if theyre all the same. I dont know if this is a valid thing to do or not though!
 

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Discussion Starter #6
Thanks again kfennel... I can try that today. At least it's a starting point!
 

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From a quick glance at the wiring diagram the number one choice is a bad multi function relay box. I would swap one in.

Next would be defective immobilizer since the feed runs from the MFRU to the immobilizer. Is your immob hacked? you are right there in the corner with the fuel pump.
After that it would sure look like ECU, just logically
 

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Discussion Starter #8
Thanks exigegus! I think the immobilizer is working since after putting the key in, pressing the button on the fob immediately puts the fuel pump into priming mode.

I found a really good clue today. Previously, I had checked the fuel pump fuse. Today I checked the immobilizer fuse and the injector/ignition coil fuse. The injector/ignition coil fuse (R7, 10 amp) was cooked! So I replaced it and tried to start the engine, but it blew the same R7 fuse again.

The injectors are RC 550cc which came with the vision function stage 2 supercharger.

Is there a test I could do that would tell me if I should be investigating the ignition coil or the injectors?

I am going to try and look at a wiring diagram next and see if I can come up with some potential tests to narrow it down further. Exigegus, do think the relay could still be involved with this new information?

Thanks again forum members for all your help!
 

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Those fuses work along side the MFRP... start with that and REPLACE it.... they’re old now and not good to begin with. Careful, they look very similar to the front MFRP, but they’re different... check the splices where the adapters go to the injectors...

-Phil
 

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Discussion Starter #10
Thanks Phil! Well this is slightly embarrassing... I definitely will check the MFRP and probably replace it if it hasn't been done recently.... Except I don't know what an MFRP is. Lol! ?
 

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Discussion Starter #12
Thanks! You guys are awesome.

Do you know if Toyota or an auto shop would carry those for the Celica? It would be nice to pick one up today instead of waiting a couple of weeks for one to ship.
 

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Discussion Starter #13
Great news... I found the problem! I removed the electrical connectors from all four injectors and tried to start the vehicle and the injector/ignition coil fuse (R7) did not blow.

When I put the connectors back in I turned the key and noticed that the pump stopped pumping after a couple of seconds instead of running forever like it had been doing! So I hit the start button and it fired right up. I'm not 100% sure what fixed it, but my theory is that while I had the connectors off, I noticed that one of the wires going to a connector had some electrical tape that was just below a very small (less than 1mm diameter) knick where the insulation had rubbed off. I slid the electrical tape back over that little section - I think perhaps it had been touching the engine block.

I still might replace that relay box since it is known to have issues.

I want to replace the connectors that snap to the top of the injectors. The wires and plastic are stiff from the engine heating and cooling and one of connectors has broken plastic, and that electrical tape doesn't seem like a very permanent fix. I can't tell where those wires go, but I suspect they are part of the wiring harness. I'm not sure where I could buy 4 of those connectors to splice+solder them in. Any ideas?

I also noticed that the little rubber rings above some of the injectors are worn pretty badly. They're RC 550cc injectors. Do you know if those can be bought at an auto part store or Toyota dealer?

Thanks again for all your help!
 

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I want to replace the connectors that snap to the top of the injectors. The wires and plastic are stiff from the engine heating and cooling and one of connectors has broken plastic, and that electrical tape doesn't seem like a very permanent fix. I can't tell where those wires go, but I suspect they are part of the wiring harness. I'm not sure where I could buy 4 of those connectors to splice+solder them in. Any ideas?

I also noticed that the little rubber rings above some of the injectors are worn pretty badly. They're RC 550cc injectors. Do you know if those can be bought at an auto part store or Toyota dealer?

Thanks again for all your help!
You can buy the RC 500cc injector connectors and splice them in. I picked up a few on Amazon. They come in a pigtail sytle or you can buy a version and crimp and assemble them your self. Not sure if an auto parts store will carry that part or not. Just search for EV-14 connectors (believe that is what fits the 550cc injectors).
 

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Discussion Starter #15
That's perfect! Thanks LostPawn, I just ordered a set! I found the o-rings at autozone.
 

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Discussion Starter #16
Ok I thought I found the O-rings at autozone... Turns out that they were not the right size. I searched all over and only found an outdated part number in these forums so I bit the bullet and ordered rings from RC at $2 each.... Ouch!
 

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Discussion Starter #17
I ordered a bunch of EV-14 pigtails and they do not fit the RC550s. I ended up calling RC Engineering and ordering one. It was $10.
 

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I ordered a bunch of EV-14 pigtails and they do not fit the RC550s. I ended up calling RC Engineering and ordering one. It was $10.
I've very sorry the EV-14 didn't fit your RC550s. We must have different brand of injectors as they fit mine, just checked that they are in fact EV-14 as I ordered more than 4 when doing mine. Someone might want them if you cannot return them.
 
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