Engine stalls

Thanks for the fast reply. Now here's what else I found. Tried to start it today but it didn't even fire. It turns over but no start. So I started checking voltages and found the fuel pump is only getting 6.8 - 7.0 volts. I went back to the cut off switch and it to has only the 7 volts. I swapped the relays around twice and no change. The fuse has 12 v and after pulling the relay it to has 12 volts to it, I believe on terminal 87. I don't know where to check it from here except I found a fuel system diagram some where and it looks like the voltage should be coming from pin 40 of the PCM. I'm not sure if I should unplug the PCM connector to check it there. I not sure if there's some thing else making it put out that low voltage or if that may be normal. I'm don't know where to go from here. Thanks again for your fast reply. Oh I'll change the crankshaft position sensor tomorrow if I can get the chance. Thanks again. Jim

Sorry Joe, I had a few meetings yesterday, but here's what I did so far. I made sure battery was fully charged. I can't start the engine in step 12 of testing relays, so I went on to step 13 with the relay out of circuit and jumped 30 & 87 got 12 v until I turned on the ignition and blew the 20 amp fuse. Before I jumped pins 30 & 87 I checked voltage on both & found 12 v on 87 not on 30. Your diagram says it should be on 30. I put the relay back in and put my Fluke 73 DMM on pump connector across pin 1 & 3 which should be the P/B & B wires to motor. Turned ignition on got 12 v for 2 seconds the it dropped to 6.8 - 7.0 v. I still don't get a service engine code. I'm using a Micro Mechanic Engine Light Check and is says no problems. A little about me. I'm a board level electronic tech. I repair PA Systems, power amps, musical instrument amps, LED light fixtures and systems. I'm not an auto mechanic but know how an engine works except for electronic engine controls and computer systems in the auto world. With that in mind, guild me thru your testing ability. I added an image of the diagram I'm using. Most of my voltage readings are to ground.

I don't know if the pump ran. When I turned the engine over, I don't think the voltage came back up. I'll check that again. I switched the fuel relay with 2 other relays. There are 6 relays with the same part number in the battery junction box. I swapped it with main fan and add fan relay, no change. Maybe I should be sure the pump is still working. How would I do that? Maybe hook up another 12 v source? I have adjustable DC power supplies rated up to 30 amp. Or another battery from my Jeep. Just take it out of the car and hook it to the pump motor wires. I'll try that next, I guess. Thanks for being so patient with me. I'll let you know what I find. Jim

Using the battery in the car, I checked the volts at the pump and got 12.74 v when I turned the ignition on. Then it dropped back to 6.8 v. Then I tried to start the engine and it came back up to 10.48 v. I don't know if the voltage drop is normal or not. Then I put a hose on the bigger output connection to a bucket and tried it again and I didn't get any fuel. I tried that with the smaller output connection and didn't get any fuel there either. A friend brought over an other fuel pump from a 2004 Mazda Tribute V6 and put it in and I get the same results. He says his pump came out of a running engine that the trans was bad. I don't know for sure if his is really a good pump. What do you think I should do next? Again thanks for being so patient we me.

No, but I will do that and try it again and get back to you with the results ASAP. Thanks and I do hope that fixes it. Jim

Yes, it starts with starting fluid, and the relay checks good and has been changed with others of the like. The 20 amp fuse is good and shut off switch checks OK in the tripped and reset position. I changed the crankshaft position sensor with a new one and tried it again. Turns over but no start, but will with starting fluid still. I bet I'm a pain in the, and again thanks, Jim. PS I'm learning a lot though. Lot different from transistors, bias circuits, o/p drivers and op-amps.

I ran a long cable (14 ga) from the positive post of battery to the pump and put a pin test lead through the PNK/B cable and it didn't run. I took the negative cable off the battery and clamped a long cable to it (not the post) and checked the ground from there to the pump. It showed.3 ohm. I did the same thing from the relay pin 87 to the pumps PNK/B wire got the same thing, .3 ohm. I'm using a Fluke 73 DMM for a meter
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I understand that's not under a load, but I don't know how to test it any other way but check the voltage drop when it's running which it not. The voltage drop I got before could have been caused by a shorted motor, I guess. Could the pump have started failing at first and finally gave it up? I guess now it's time to get a new pump?

I couldn't find where the splice was but I did check the resistance of the switch in the open and closed positions and got.02 ohm closed (test leads) and OL in the open position. Let me know what you think.

I;m prepared to purchase another pump and if that doesn't do it then I'll replace every thing including the high $ switch and low $ relay and fuse and finally run new cable from the relay to the switch and then to the pump. Anyways let me know what you think now. I'm sorry for being a pain but you sure are great at helping me. I sometimes get customers like me too, and what a pain they are.
Thanks again, Jim

Hey Joe,
Thanks for all your help. I figured we spent enough time on this project, so I broke down and bought a fuel pump and varoom off she went. I also got a couple of connectors to replace a few tore up ones. So far it's idling sooth. I haven't been on the road yet, but I will be soon.

I can't thank you enough for your time but if there is a way, let me know.

Put Ken on line

Hello, Ken? I want you to know you have one great mechanic. Joe's the kind of employee I wish I could find in my business. Thanks for having a company that's for the DIY'ers. Let me know how I can help promote your business. Thanks again and warning, I'll be back if I have more problems. Jim

Battery died after using radio for over an hour without the vehicle running, got a jump and drove home. The next day it started and when my wife turned the headlights on it almost shut off and she panicked and cut it off it would not start again. I jumped it again and pulled the battery cable to see if the alternator would keep it running and it shut off immediately.