No fuel Pressure
#1
No fuel Pressure
Here is the low down. I was driving to work yesterday and all of a sudden my 86 22RE 4Runner started losing power. I got in a parking lot and it shut off. Smoke started bellowing out from under the hood. It over heated because a coolant line busted. I got it towed back to the house changed line, added coolant, turned key, and another problem. The starter is turning, the crank is turning, spark is happening (put my timing light on each wire), but still nothing is happening. I went back and dissconnected my fuel lines turned the key over no fuel came out. Is there a fuse somewhere that I am not aware of? What does anyone think. Please help!!!
#2
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Fuel pump normally does not run unless the engine is running or the test jumper is installed:
- http://www.4crawler.com/4x4/CheapTri...shtml#FuelPump
- http://www.4crawler.com/4x4/CheapTri...shtml#FuelPump
#4
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Check that all the wiring and plugs and connections in and around the igniter and air filter are clean and dry- any moisture could interrupt the signal to the ECU that triggers fuel injection events. That is not likely the problem though since the fuel pump should operate while cranking the engine and once the engine has started (as determined by adaquate air flow through the air flow meter).
There is a relay located above the ECU called the Circuit Opening Relay (COR) and it turns on in response to either of two signals. If you understand how a relay works, picture it as a relay with two coils inside, either one of which can turn it on. 4Crawler's diagram on the link he provided shows what I mean.
One relay coil receives power from the ECU STA wire (which has power only when the ignition key is turned to "Start" position, something left off of the diagram) and the other coil has power but gets grounded through the air flow meter.
You can attempt to manually turn on the COR by jumpering between the two terminals in the FP test connector, completing a circuit which is parallel to the air-flow meter's contacts and try to start the engine. If that doesn't work and the connectors around the igniter are in fact dry, in particular the one to the air-flow meter, I'd go to the COR and start checking for issues there.
On a tangent: have you ever had or noticed an issue where it takes more than a second or two of cranking to get it started?
There is a relay located above the ECU called the Circuit Opening Relay (COR) and it turns on in response to either of two signals. If you understand how a relay works, picture it as a relay with two coils inside, either one of which can turn it on. 4Crawler's diagram on the link he provided shows what I mean.
One relay coil receives power from the ECU STA wire (which has power only when the ignition key is turned to "Start" position, something left off of the diagram) and the other coil has power but gets grounded through the air flow meter.
You can attempt to manually turn on the COR by jumpering between the two terminals in the FP test connector, completing a circuit which is parallel to the air-flow meter's contacts and try to start the engine. If that doesn't work and the connectors around the igniter are in fact dry, in particular the one to the air-flow meter, I'd go to the COR and start checking for issues there.
On a tangent: have you ever had or noticed an issue where it takes more than a second or two of cranking to get it started?
#5
Yes I have had problems getting it to start on first couple of cranks in fact it takes a few times. Also after it is started and I drive a short distance and come to a stop it stalls out, but then it will start up right back up. After I have drove a few miles it is fine. I was thinking this was the coolent sensor. I tested the pump today by running wires to it and it pumps so obviously it is not getting power. I tryed jumping the terminals that didnt work but I am going to give it another try. Is there a fuse for the fuel pump? I checked all my fuses and they look good. Thanks for all the great info keep it coming.
#6
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No specific fuse for the pump. Look at 4Crawler's diagram and you'll see all the fuses, relays and such involved in most of the circuitry. I'll try to get a complete engine wiring diagram for an 86 22RE posted shortly.
#7
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wiring diagram: 86 Engine Wiring. Right click to download.
It's a bit over 3MB to download so it should be high enough quality to print. If you need a better pic, let me know, but I zoomed in to 100% and was able to scroll around and read it all fine.
It's a bit over 3MB to download so it should be high enough quality to print. If you need a better pic, let me know, but I zoomed in to 100% and was able to scroll around and read it all fine.
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#8
Great Pic thanks. I am really pushing my electrical knowledge here, I am to much of a knuckle dragger. Looking at it though I think it should start if I jump those connections. So I think it is a fusible link and these are the ones under the hood. Right? They all look good I think I will pull them and test there continueity. Do you find it strange that this all happened after the engine overheated?
#9
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Great Pic thanks. I am really pushing my electrical knowledge here, I am to much of a knuckle dragger. Looking at it though I think it should start if I jump those connections. So I think it is a fusible link and these are the ones under the hood. Right? They all look good I think I will pull them and test there continueity. Do you find it strange that this all happened after the engine overheated?
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Great Pic thanks. I am really pushing my electrical knowledge here, I am to much of a knuckle dragger. Looking at it though I think it should start if I jump those connections. So I think it is a fusible link and these are the ones under the hood. Right? They all look good I think I will pull them and test there continueity. Do you find it strange that this all happened after the engine overheated?
I mentioned it above, check the connections around the igniter, coil and air filter. That connection to the air filter housing is for the air-flow meter and if it's not making good connections will not let the fuel pump run. You mentioned you put the jumper in the pump test connector and that didn't help. Well, I would guess that had coolant sprayed all around the engine bay, both of those connectors would've got a bit of coolant in them since they're both on the same side of the engine bay. Moisture can do weird things- it can be an insulator and break connections and be a conductor and make the wrong connections. Pull the plugs apart and spray some WD-40 and let it set a moment, then spray some rubbing alcohol- enough to make things drip of it, then let it dry and see what happens when you plug them back together.
To me though, it still appears you have an issue back at the COR. I have given you a wiring diagram and you should be able to figure out, based on color codes alone, which wire leads to the fuel pump and then insert a jumper there giving the fuel pump some voltage.
Good luck.
#12
You are right I had coolant everywhere, but it on right side of the engine. It is where the smaller hose comes off of the water pump and turns back 180 degrees to the intake manifold. I will clean the connections though and see what it does, it definitly wont hurt. I am thinking it is the COR relay also, but if I tried jumping it and it still didn t work can it still be the COR? Is there anyway I can manually close the switch at the AFM? Again thanks for everyones help.
#14
Ok so here we go. I replaced the COR relay no I am getting fuel pressure. NEXT problem still no start. Pulled spark plugs and grounded them to the block the spark was orange and looked weak. Replaced plugs and replaced the ignitor coil for giggles. Still no go. So I start testing everything with my multimeter everything tests as advertised. I think it is the igniters. When attempting to start it an occasional poof is heard from the tail pipe. Also I attempted to test the ignitor with my meter and it did not show anything. Any ideas on this, the wires for the igniters run close to the coolant line that busted. I am hoping it is not the ECU. Please any help.
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