New fuel pump. Still no start?

[AHTex]

Hey all,

Short story long, I have a no start issue. Ill list what I did to diagnose below, but with a new fuel pump installed, I still have a no start condition. Im really scratching my head here. Anything im missing here?

1997 4cyl 2wd 3rzfe
-Verified spark
-Engine will start up with starting fluid, then die
-battery, starter, all good
-checked efi fuse, efi relay, cor relay, all good
-power present to the pump
-applied 12v directly to pump, (per fsm)nothing
-dropped tank, replaced pump, (with a denso) still nothing
-got frustrated, called it a day.

 

[Acorn22]

How was it running and driving before? Did it just randomly happen to where it didn't start up or was it on a decline in performance that could be traced back to a bad fuel pump?

 

[TheDurk]

Well, time to apply 12V directly to the new pump, and then go from there. If it runs, then see if 12V+ is being sent to the pump connector when engine cranks.

 

[Toyotayoda]

probably the wire thats in the tank, theres that small harness between the top of the tank and the pump, it can go bad. either that or no ground.

 

[AHTex]

Its been parked for about two years. Ran fine before parked. Yeah, I guess I need to start from the top of the diagnosis tree and see what happens. On a plus side, my learning curve with dropping the tank should be improved. I hate throwing parts at problems, but thought for sure it was the fp. Didnt think about the wiring inbetween, although I did get some resistance through the pump i believe. Im going to start with trying to bench test the old pump. Maybe that will point me in a direction.

 

[IBallEngineer]

Its been parked for about two years. Ran fine before parked. Yeah, I guess I need to start from the top of the diagnosis tree and see what happens. On a plus side, my learning curve with dropping the tank should be improved. I hate throwing parts at problems, but thought for sure it was the fp. Didnt think about the wiring inbetween, although I did get some resistance through the pump i believe. Im going to start with trying to bench test the old pump. Maybe that will point me in a direction.

OK, I'm late to the party, but the red flag here is the length of time sitting. You are saying "still nothing", but have you verified fuel is not getting to the fuel rail? Maybe you have something plugged? Two years isn't that long, but I've seen fuel sitting on top of injectors dry up and completely shut off fuel. Plus the injectors can get stuck. Just sayin'.

Did you use an ohmmeter to check the old pump, AND the new pump to see if you have a complete circuit?

 

[LiquidFlame]

I was going to say injectors just like IBall did, as well as maybe a clogged/old fuel filter?

 

[Ricktuk]

Did you use a Jumper wire to put 12 volts to the pump? Had similar prob in an Eclipse turned out to be a bad wire.

 

[AHTex]

Im going to get into it further today. Thanks everyone for giving me a few options to further diagnose. Its nice to have a community to bounce problems off of. I know its the in the fuel system, I just have to find it. How many other things can it be?

 

[AHTex]

Okay, I went back out for a bit to diagnose, and I mean a bit because its 95+ degrees down here. I bench tested the old pump and got nothing. Applied 12v to the new installed pump and it started right up. Which is a relief to say the least. Hopefully that means I dont have to drop the tank again! So I will go through the electrical circuit again and see if thats still ok. A few questions are, how do I test for ground to the circuit? Is it possible that I just need to prime it a few times? What is a definite way to verify fuel pressure at the rail? I dont have the toyota sst.

 

[TheDurk]

Okay, I went back out for a bit to diagnose, and I mean a bit because its 95+ degrees down here. I bench tested the old pump and got nothing. Applied 12v to the new installed pump and it started right up. Which is a relief to say the least. Hopefully that means I dont have to drop the tank again! So I will go through the electrical circuit again and see if thats still ok. A few questions are, how do I test for ground to the circuit? Is it possible that I just need to prime it a few times? What is a definite way to verify fuel pressure at the rail? I dont have the toyota sst.

To test for ground, place one lead of meter or test light on a 12v+ source, battery positive is fine. Any ground will show 12V when the other lead is touched to it.

 

[69project]

Okay, I went back out for a bit to diagnose, and I mean a bit because its 95+ degrees down here. I bench tested the old pump and got nothing. Applied 12v to the new installed pump and it started right up. Which is a relief to say the least. Hopefully that means I dont have to drop the tank again! So I will go through the electrical circuit again and see if thats still ok. A few questions are, how do I test for ground to the circuit? Is it possible that I just need to prime it a few times? What is a definite way to verify fuel pressure at the rail? I dont have the toyota sst.

I am new to 4Runners but with a fuel injected vehicle there is usually a Schrader valve on or near the fuel rail where you can put a gauge on and check fuel pressure.

Are you using new gas? After sitting for 2 years whatever gas was in that tank has to be bad or damn close, especially with E10 or greater gas.

I would work your trouble shooting from the tank forward. Sounds like you have eliminated the fuel pump. I would replace the filters next if you haven't already and then start checking the injectors.

I am thinking crappy gas or plugged fuel filter/injectors since you said it runs on ether. Run some sea foam through it and see if that fixes it.

 

[IBallEngineer]

I am new to 4Runners but with a fuel injected vehicle there is usually a Schrader valve on or near the fuel rail where you can put a gauge on and check fuel pressure.

Are you using new gas? After sitting for 2 years whatever gas was in that tank has to be bad or damn close, especially with E10 or greater gas.

I would work your trouble shooting from the tank forward. Sounds like you have eliminated the fuel pump. I would replace the filters next if you haven't already and then start checking the injectors.

I am thinking crappy gas or plugged fuel filter/injectors since you said it runs on ether. Run some sea foam through it and see if that fixes it.

I don't know of a Schraeder on a 3RZ, but the regulator at the end of the fuel rail is an easy thing to loosen and see if you are at least getting fuel that far. I don't think pulling the rail is that easy because it is under the manifold.

 

[AHTex]

Yeah, no schrader valve on this one. Im pretty new to 4runners myself, and must say that some of the engineering is complex. The fsm says to attach some special fitting to the banjo bolt at the rail to check for pressure. Well as said, thats under the intake. (I believe) I also found the fuel filter under the intake too. That should be fun! Why wouldnt it just be on the frame? Haha. Anyhow I dont have to drive it to work on monday so im enjoying the process. Thanks again for all the input.

 

[19963.4lsr5]

I'm pretty sure that's a pressure regulator under the intake. Unless things changed on the newer models. I just seen your 97 is a 4cyl. Oops That may change the filter location. My 97 is on the frame. But the V6.......


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