Fuel issues
#1
Fuel issues
Hey everyone, I'm having some issues with my fuel system hopefully someone can give me some pointers. I swapped my engine from my 89 3.0 runner into a 93 runner. Had some sort of starter to flexplate issue making a grinding noise issue, after trying to bump start it a few times she started up and ran fine. Started it up a few other times and let her get to standard OP temperature. Right before I was about to drive on the road for the first time she died on me. I tired to start the car again and she turned over fine but did not start so I tried a few times and and got nothing. I thought fuel pump for sure. I have spark. The EFI fuse and relay are both good I'm getting about 25 ohms of resistance in the relay. My circuit opening relay behind my passenger side kick panel is good as well. I replaced the VAF. The other one I had on has some rattling sound on the inside of it. If I jump my terminals in the diagnosis port I can hear the new fuel pump start up but when I try to start the car still nothing. If I spray starter fluid in the intake she starts up but of course dies quickly after. Does anyone know where i go after this?? I am an idiot when it comes to electronic diagnostics so if you know the issue please be thorough in your response. Thanks guys!
#2
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Help us help you. What engine was in the rig before you replaced it? Did you clean the tank when you replaced the fuel pump? When they sit they can get really bad scale build up. Could be something as simple as dropping the tank and cleaning it. Are you getting fuel to the fuel filter? What do your plugs look like. Are they dry or wet, (after trying to start it without starting fluid).
This sounds like you have a clog in between you tank and engine.
This sounds like you have a clog in between you tank and engine.
#3
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If you get enough fuel out, it's still possible a failed FPR gives you too little pressure. You'll need to plumb in a pressure gauge to check that. Or, you could remove the CSI from the plenum (don't remove the fuel line from the CSI; if you do, you HAVE to replace the crush washers). Run the pump, then trigger the CSI with 12v to the terminals. You should get a good spray; if you only get a dribble I would suspect fuel pressure (and by that point, you need to get the gauge).
If you have enough fuel pressure, the next step is to check injector function. But run the checks in order; you can go through a lot of money replacing fuel pumps and VAFs on guess-and-by-golly.
#4
Help us help you. What engine was in the rig before you replaced it? Did you clean the tank when you replaced the fuel pump? When they sit they can get really bad scale build up. Could be something as simple as dropping the tank and cleaning it. Are you getting fuel to the fuel filter? What do your plugs look like. Are they dry or wet, (after trying to start it without starting fluid).
This sounds like you have a clog in between you tank and engine.
This sounds like you have a clog in between you tank and engine.
#5
So let's find out. Get some 6mm (1/4") clear vinyl tubing, disconnect the fuel return from the FPR, and run the vinyl to a suitable container. (This is low pressure, so there are no crush washers to replace). Run the fuel pump with the jumper. I get about 1/2 liter/min out with the engine not running. If you get nothing, the fuel pump is not pumping, or you have a blockage somewhere.
If you get enough fuel out, it's still possible a failed FPR gives you too little pressure. You'll need to plumb in a pressure gauge to check that. Or, you could remove the CSI from the plenum (don't remove the fuel line from the CSI; if you do, you HAVE to replace the crush washers). Run the pump, then trigger the CSI with 12v to the terminals. You should get a good spray; if you only get a dribble I would suspect fuel pressure (and by that point, you need to get the gauge).
If you have enough fuel pressure, the next step is to check injector function. But run the checks in order; you can go through a lot of money replacing fuel pumps and VAFs on guess-and-by-golly.
If you get enough fuel out, it's still possible a failed FPR gives you too little pressure. You'll need to plumb in a pressure gauge to check that. Or, you could remove the CSI from the plenum (don't remove the fuel line from the CSI; if you do, you HAVE to replace the crush washers). Run the pump, then trigger the CSI with 12v to the terminals. You should get a good spray; if you only get a dribble I would suspect fuel pressure (and by that point, you need to get the gauge).
If you have enough fuel pressure, the next step is to check injector function. But run the checks in order; you can go through a lot of money replacing fuel pumps and VAFs on guess-and-by-golly.
Ok I will go to the Ace by my house and pick up some tubing and start from there. I'll have to let you know way later today what I found or maybe tomorrow. I will be a little busy with it being fathers day today.
#6
Sorry I have not got back to this thread in forever I've been out of town for a while now and have not had time to work on the runner. I'm back for a few weeks and ready to figure this thing out. So I do have fuel coming through the lines and seems to be quite a bit of fuel (about half a cup after cranking the engine over 6 or 7 times. I changed the plugs and wires just because the plugs needed to be changed sometime soon and the wires because the ones that were on were installed were some cheapo brand. I also replaced the fuel pressure regulator just because I had one laying around and I figured maybe, just maybe this was a contributing factor. So the engine will start after usually after a day or 2 of sitting and run just fine then once I turn the engine off and wait min to start up again she won't start. Just today I started her up after replacing the regulator and she started right up and I let her run to about 1/3 of the operating temp. She started smoking a little to much for my liking because the valve covers used to leak so there is oil still in the engine. But after a few mins I tried to start the engine again and it turns over great but will not start.
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