Fairtax4me Posted April 11, 2011 Share Posted April 11, 2011 so assuming this is all right. i take the sensors one at a time. while cranking the enigne and the sensors hooked up. with my volt meter set to ohms and i check for 3-4 of resistance on each sensor? and they will be pulses. if i get those pulses of that resistance level then the sensors are good No. The resistance check is to see if the sensors are open (internal problem). The cam and crank sensors create a small AC voltage wave when the engine is running. You can check this with an analog voltmeter set to AC volt. The voltage is low, and the pulses happen faster than most digital meters are able to display. More than likely you will see no reading, or only small erratic reading with the meter shown in your pic. I can't make any sense of the wiring diagrams in the FSM right now. The diagram in the troubleshooting section says the coil gets power from the fuse panel through the main relay. The diagrams in the wiring section say coil power comes from the fuse panel, but not through the main relay. So I'm not sure which one is right. But either way, power for the coil comes through the fuse panel. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 11, 2011 Author Share Posted April 11, 2011 someone on another forum is telling me that 12 volts is suppose ot be to the injectors all the time and that is also power to the coil. and they only work if the ecm supplies ground. i think he is wrong. i have aocsiscope. but no leads for it. my analog meter doesnt work for some reason. all i have is this high voltage meter right now. i watched a little you tube stuff tonight and am going to try a few checks. with maybe my check engine lights and codes. s well i am going to try and check the crank sensor pulses. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 11, 2011 Author Share Posted April 11, 2011 ok this is becoming stupid or something. it looks like i was checking the wrong side of the fuse for power. the first tiem i was checking it i had no power to one side and only .8 to the other side. i thought that was the power side. i guess not. so now i have power to the fuse. but now no power at all to the eninge harness behind the battery. i had the fender off this weekend to look at the wiring harness up in there. i didnt see any faults. i do have complete power to the fuseable link. and the fender box. my injectors do not have power running to them all the time when the key is on. what are the test procedures from here? what do i check or test next? Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 11, 2011 Author Share Posted April 11, 2011 update. i removed the fuel line from the filter and confirmed i am also not getting fuel either. so it has to be soemthign controillign the fuel and the spark. or it is just a coincedence that both are not working. i did have fuel the first day it wouldnt start. i could smell it. also starting fluid has not done anything. except for that attempt to start the engine the other day. but that lasted only a second and the starting fluid had probably already dried up by then anyway. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 11, 2011 Share Posted April 11, 2011 (edited) Looks like the person on the other board was right. The fuel injectors get 12V power straight from the main relay. The injector grounds are switched by the ECU. The main (ignition) relay draws power from Slow Blow Fuse number 2 in the under hood fuse panel. You can check fuses with them still in the panel by placing the probe on the small tabs that stick out of the top of the fuse. This makes it easier to check if the fuse is blown. The main relay is grounded through the engine wiring harness. That ground point is on the back side of the drivers side head near the rear intake runner. Check that 12V is reaching the main relay on both of the two large yellow wires. Check resistance/continuity to chassis ground on the black and white wire at the relay connector. Throw side of the fuel pump relay (the side that delivers power to the pump) gets 12V from SBF2 as well. Edited April 11, 2011 by Fairtax4me Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 11, 2011 Author Share Posted April 11, 2011 i have power to the fuel pump relay. i couldnt jump it and make the fuel pump kick on. i only crossed one terminal at a time though. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 11, 2011 Share Posted April 11, 2011 The pull side of the fuel pump relay gets power from fuse 16, then is grounded through the ECU. Both power wires on the relay are yellow. You should have 12v on both with the key ON. Did you check for power at the Main relay as well? Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 12, 2011 Author Share Posted April 12, 2011 where is this main ignition realy? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 12, 2011 Share Posted April 12, 2011 (edited) According to ShawnW, right next to the fuel pump relay. The main relay has 6 wires. All of them are fairly large. Two yellow, two yellow with red, one green and one black w/ white stripe. Edited April 12, 2011 by Fairtax4me Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 12, 2011 Author Share Posted April 12, 2011 According to ShawnW, right next to the fuel pump relay.The main relay has 6 wires. All of them are fairly large. Two yellow, two yellow with red, one green and one black w/ white stripe. that is what i thought the fuel pump relay was. it is a brown connector with a brown relay. it has all those colors of wires going to it. only one of those wires has any power to it. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 12, 2011 Share Posted April 12, 2011 Both yellow wires should have 12V. Both yellow / red should show 12V with ignition on. The green should be 12V with ignition on. The black/white is ground. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 12, 2011 Author Share Posted April 12, 2011 i have one power in that brown relay. that is all. i did find the ground. i was crossing terminals to activate the fuel pump. that didnt work though. i could only see this relay up in there. it was kind of hanging loose. behind the fuse box is a red relay looking thing. there is a small two wire brown connetor not hooke dot anything and another brown connector with two black plugs with writing on them. is the fuel pump relay a metal can with a plastic base with four spade connectors in it? Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 12, 2011 Author Share Posted April 12, 2011 ok i can see the fuel pump relay finally. i cant barely get up in there. i am removeign the fuse panel and bracket so i can drop it down and unsnap it or how ever its held up in there. my question is. if the fuel pump relay ia bad. would it cut the power off going to the iginition rerlay as wellas the fuel pump and cause this problem? no spark and no fuel? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 12, 2011 Share Posted April 12, 2011 The fuel pump relay and main relay get power from the same source. One does not control power to the other. The power wire colors are the same on both. Quote Link to comment Share on other sites More sharing options...
ShawnW Posted April 12, 2011 Share Posted April 12, 2011 The fuel pump relay and main relay get power from the same source. One does not control power to the other. The power wire colors are the same on both. Nice job and info. Going to get to the bottom of this one I am sure of it. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 12, 2011 Author Share Posted April 12, 2011 Both yellow wires should have 12V. Both yellow / red should show 12V with ignition on. The green should be 12V with ignition on. The black/white is ground. ok i can see the fuel pump relay finally. i cant barely get up in there. i am removeign the fuse panel and bracket so i can drop it down and unsnap it or how ever its held up in there. my question is. if the fuel pump relay ia bad. would it cut the power off going to the iginition rerlay as well as the fuel pump and cause this problem? no spark and no fuel? ok if both yellows are suppose to have power. one of those yellows comes from the pump relay to the ignition relay. and there is a wire coming from the ignition switch inbetween them. on that yellow wire. so the ignition switch is the one giving power to both units as a second power source to tell them for a few seconds anyway to come on get ready to start. that is why the fuel pump will tuirn on and start up when the key is turned on. i know the switch isnt bad. i have a different switch i plugged in and that didnt start the car either. so all of this leads me to believe the igntion relay is the bad one. if it is not putting out power when crancking. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 12, 2011 Author Share Posted April 12, 2011 i pulled the fuel pump today because i wasnt getting any power back there. and wanted to check the pump anyway. so why would i not be getting any power back there? oops edit: the pump does work. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 12, 2011 Author Share Posted April 12, 2011 it is either the ecm or a bad wire we are thinking. i retested. and have two power wires now going to the ignition relay. still no power back to the fuel pump. and i cant find my extra fuel pump relay either. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 13, 2011 Share Posted April 13, 2011 have two power wires now going to the ignition relay. Which two? You should see 12V on all 6 wires when the key is on if the relay is connected. If you unplug the relay, you should only have power on the the yellow wires and the green one. so why would i not be getting any power back there? I would imagine it is because the fuel pump relay is not activating. The ECU controls the ground side of the relay. The main relay sends power to the ECU. If the ECU does not turn on, (say because the main relay is bad, or one of the power wires is not getting 12V) it can't ground the pump relay, so the pump doesn't get power. The main relay is a single pull double throw type relay. One coil pulls two separate gates. Either gate can fail, whether is due to a weak coil not pulling correctly, corrosion/arcing leading to wear of the contacts, or just long term use eventually wears it out. To determine if the relay is working properly, you need to check input and output power leads. The inputs are yellow, the outputs are yellow w/ red stripe. With key on you should see 12V on all four of those wires. one of those yellows comes from the pump relay to the ignition relay. and there is a wire coming from the ignition switch inbetween them. That is the 12V+ for the relays. On those wires you should have 12V at both pins on the main, and the one pin on the fuel relay. If you have 12V at one or two, but not all three, there is a break in the wire. it has all those colors of wires going to it. only one of those wires has any power to it. Which one? Is the key On? Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 13, 2011 Author Share Posted April 13, 2011 what a total drag this is getting to be. i need someone here to turn the switch on and off when i am testing so that i can properly read before the relay shut off. after the key is left in the on position. it is hard to reach these relays with the testing probes. i have not been able to figure out if the fuel pump relay is bad or not. i would say it is. but why would it just stop workling all of the sudden at this moment? strange i think. ok power to the coil pack: with the key on i was able to remove the ignition relay and am gettign power to both yellow wires numbers 5 and 6 on the plug. i have no power to anything else in the plug. i attempted tonight to test wires going to the ecu. but that was a mess and quit almost immediatly. i have done some more studying of those fsm diagrams thank you by the way. on page 18 section 6.3. wire color lg. goes from the igntion relay to the ecu. so the ecu isnt giving power to slot number 2 on that plug. this wire lg also intersects with another wire lg going to the mpfi diode. from the diode. wire yellow coems out and goes to alt-2 and a splice on that wire goes to yr which is on page 21 section 6.3 and ends up power to the injectors. slot numbers 5 and 6 on the ignition relay plug do now have power. slot 5 and 6 on that relay also go to the fuel pump relay slot number 2. the fuel pump relay also has slot number 1 that gets its power from fuse 16 and also fuse 16 gives power to the ecu. but the fuel pump relay only has one full power wire. and only a small voltage from the other power wire. i think slot 2 but i tmay be slot 1. i didnt pay complete attention. ok so here is what i am thinking. if wire lg from the igntion relay isnt getting power. then either the alternator or the ecu isnt letting it have power. i would suspect that the alt 2 wire isnt giving poiwer. to either the injectors or the mpfi diode. and then not to the igintion relay. now beofre this all happened. i replaced the brushes in the alternator. and the car was driven at least two days before any problems. my wife says a week but i cnat remember now. so the problem may be in the alternator? and no power out of it? that would explain the no spark. but not the no fuel relay power. i did read elsewhere that the fuel pump relay would only give power for a few seconds if it didnt sence a start command from the ignition switch. so turning the switch on and checking at the same time i didnt get a reading. but only a small one when i did get a reading. and the reading was way low like 1.2 volts. i didnt mees with it toomuch. because the fuel pump wire is burned up on the inside of the pump. so i skipped fuel testing mainly because of that wire. ok i think i now have a better idea that i had 2 hours ago. i think i needed time to not think about it. ok tomorrow check power from alternator 2. now the belt isnt on the alternator. would that kill the power to alt2? Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 13, 2011 Author Share Posted April 13, 2011 update: slot number 1 on the fuel pump relay read .8 of a volt. so it is not getting full power from the ecu. on the igntion relay slot number 2 wire color wire is only getting .2 of a volt. so it is not getting power through the diode from the alternator. the yellow wire on the alternator is not putting out 12 volts either. i am thinking that the alternator may be messed up or it has to be turning to put out voltage on the yellow wire. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 14, 2011 Share Posted April 14, 2011 There should still be 12V on the yellow wire at the alt from the fuse panel. Pin 1 is power for the pull side of the fuel pump relay, comes through fuse number 16. Pin 2 is power from SBF2 in the under hood fuse panel for the fuel pump. Regardless of relay operation you should still see 12V at pins 1 and 2 of the fuel relay with Key On. If you have 12V at the fuse panel, but not at the relay, what's in between the two? Ignition switch. The ignition switch, (the actual switch not the lock cylinder) is on the side of the steering column about halfway down. It has a 6 pin plug that should be black in color. There will be a couple of red wires, a black wire, and one or two others IIRC. One of those red wires will show 12V with the switch off. One will show 12V with the key in ACC position. Another will show 12V with key On. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 14, 2011 Author Share Posted April 14, 2011 well i checked ou tpower with the yellow wire from the alternator. i had .8 volts. so i hooked up the alternator belt and pu tmost of the car frotn end back together. and the alternator turning still didnt give me power to that wire. i tok the alternator off and had it tested. it is bad again. so that explains no power to the ignition relay. i am unsure ahy i dont have power to the fuel pump relay slot 1. it is suppose ot be a direct connection according to the diagrams. i have stoped work on it until i get another alternator. maybe tomorrow. i do have a second igintiion switch and have been testing with it plugged in and key on too. that has not changed my fuel pump relay power. unless the swithc has to be grounded. it is just hangin under the dash right now. if the junkyarc gets me a good deal i may also grab the fuel pump relay and igntiion relay out fo the junk car too. just so i dont have to make anohter trip over there. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 15, 2011 Share Posted April 15, 2011 well i checked ou tpower with the yellow wire from the alternator. i had .8 volts. so i hooked up the alternator belt and pu tmost of the car frotn end back together. and the alternator turning still didnt give me power to that wire. i tok the alternator off and had it tested. it is bad again. so that explains no power to the ignition relay. i am unsure ahy i dont have power to the fuel pump relay slot 1. it is suppose ot be a direct connection according to the diagrams. i have stoped work on it until i get another alternator. maybe tomorrow. Unless the engine was running the alternator was probably not charging. Regardless, the yellow wire should still show 12V because it gets power from fuse 16. It should be 12V with the key ON. Quote Link to comment Share on other sites More sharing options...
General chaos Posted April 15, 2011 Author Share Posted April 15, 2011 the alternator was working. and there is a long story as to why it may not be workign properly now. i have took tiem off of this to rethink my options on alternator replacement or possible repair of my mess up. chinese parts i am guessign is the real problem. Quote Link to comment Share on other sites More sharing options...
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