Adam Posted April 11, 2010 Author Share Posted April 11, 2010 (edited) Could the ignitor cause this possibly? I believe it's wired directly to the resistor and condensor part that melted that caused me to replace the majority of the harness(either that or the coil is)... I can't get a fuel pressure guage that's got high enough psi locally, but squeezing the lines while the pump is on is a chore... Edited April 11, 2010 by Adam Link to comment Share on other sites More sharing options...
Adam Posted April 11, 2010 Author Share Posted April 11, 2010 The fuel pump relay also seems to be working fine, and pressure builds in the lines when it clicks on Link to comment Share on other sites More sharing options...
Adam Posted April 11, 2010 Author Share Posted April 11, 2010 it helps if I do the compression test rigvht, I'm around 150lbs per cylinder Link to comment Share on other sites More sharing options...
Precise1 Posted April 11, 2010 Share Posted April 11, 2010 Engine coolant temp sensor doesn't help 1 bit... Is that the error code?? Yes, it matters, a lot. It tells the ECU how rich to run due to engine temp. Kingman had one fail drastically and his truck would barely run. Again, is that the ECU fault code you read?? We are trying to help but you need to slow down and work with us here... it helps if I do the compression test rigvht, I'm around 150lbs per cylinder That sounds more like the proper range, but then a bigger factor is being within a few % of the same number in all cylinders... B Link to comment Share on other sites More sharing options...
Adam Posted April 11, 2010 Author Share Posted April 11, 2010 Is that the error code?? Yes, it matters, a lot. It tells the ECU how rich to run due to engine temp. Kingman had one fail drastically and his truck would barely run. Again, is that the ECU fault code you read?? We are trying to help but you need to slow down and work with us here... That sounds more like the proper range, but then a bigger factor is being within a few % of the same number in all cylinders... B 3 and 5 were at 140 or 142ish, the rest were at 148-150. The plugs came out with a little bit of fuel on them during this. All cylinders but 1 had some black soot on the plugs, cylinder 1 is a light tan soot. Link to comment Share on other sites More sharing options...
Adam Posted April 11, 2010 Author Share Posted April 11, 2010 Exhaust smells strongly of fuel... Link to comment Share on other sites More sharing options...
Precise1 Posted April 11, 2010 Share Posted April 11, 2010 See above... B Link to comment Share on other sites More sharing options...
Adam Posted April 11, 2010 Author Share Posted April 11, 2010 Just checked spark at the spark plugs, they all fire... I'm running Bosch Platinum +2's, is that alright for this truck? I can't honestly remember why I bought them when I did... Gonna go pick up the coolant sensor now, since I know it's actually out, and it's in stock at Auto Zone. Link to comment Share on other sites More sharing options...
Adam Posted April 11, 2010 Author Share Posted April 11, 2010 Replaced the sensor, I verified the code is gone, same problem. Link to comment Share on other sites More sharing options...
Adam Posted April 11, 2010 Author Share Posted April 11, 2010 (edited) Is there a second temp sensor I need to worry about? I saw one in the howto section that's near the water pump, but I can't find said sensor on my Pathfinder... Is the cylinder head sensor VG30i only, or maybe in a different location on the VG30E? Edited April 11, 2010 by Adam Link to comment Share on other sites More sharing options...
adamzan Posted April 12, 2010 Share Posted April 12, 2010 The two sensors on the vg30e are right beside each other. The one for the ecu is the one with the yellow connector IIRC Link to comment Share on other sites More sharing options...
Adam Posted April 12, 2010 Author Share Posted April 12, 2010 (edited) The two sensors on the vg30e are right beside each other. The one for the ecu is the one with the yellow connector IIRC Ahh, that's the one I replaced... I'm really at my wits end here... I'm not sure how to proceed, I feel like I've touched everything... Unless it's inadequate spark... I'm really at a loss right now... Compression is good, getting fuel, getting spark, code gone... Could a worn distributor cause anything like this? I'm just grasping at straws rightnow... The rotating assembly seemed pretty solid, I sanded the terminals on the inside of the distributor cap cause they had some filth on them... didn't take more than 1/1000th of an inch off, it was really a light sanding... The way I got Cyl 1 at TDC is the same way as in the manual, so the distributor is correctly indexed... Edited April 12, 2010 by Adam Link to comment Share on other sites More sharing options...
Adam Posted April 12, 2010 Author Share Posted April 12, 2010 Man, I keep throwing parts at this I'll wind up with an entirely new Pathfinder Link to comment Share on other sites More sharing options...
adamzan Posted April 12, 2010 Share Posted April 12, 2010 Could it be an injector maybe? There are tests in the FSM for them... Link to comment Share on other sites More sharing options...
Adam Posted April 12, 2010 Author Share Posted April 12, 2010 Could it be an injector maybe? There are tests in the FSM for them... Ill look tomorrow, I'm so tired after this weekend, I just want to vegg... Link to comment Share on other sites More sharing options...
Kingman Posted April 12, 2010 Share Posted April 12, 2010 It's been said before many times, not in this thread, but if the ECU Coolant Temp Sensor starts to go bad it won't throw a code unless it's completely gone. The sensor is located in the valley of the block below the intake manifold. It's a bitch to get to and if it malfunctions it'll throw an insane amount of gas through the engine and can damage a lot of other things. When mine finally gave out after a few months of it playing tricks on me, I used a half a tank of gas in 14 miles. Yes you read that right. It would barely run, poured out black smoke, misfired like a mofo, etc. It's a $20-$30 part, however having a shop replace it can bring the repair bill up towards $1000 due to being labor intensive. Mine was $856.xx at a local shop. Link to comment Share on other sites More sharing options...
Adam Posted April 12, 2010 Author Share Posted April 12, 2010 It's been said before many times, not in this thread, but if the ECU Coolant Temp Sensor starts to go bad it won't throw a code unless it's completely gone. The sensor is located in the valley of the block below the intake manifold. It's a bitch to get to and if it malfunctions it'll throw an insane amount of gas through the engine and can damage a lot of other things. When mine finally gave out after a few months of it playing tricks on me, I used a half a tank of gas in 14 miles. Yes you read that right. It would barely run, poured out black smoke, misfired like a mofo, etc. It's a $20-$30 part, however having a shop replace it can bring the repair bill up towards $1000 due to being labor intensive. Mine was $856.xx at a local shop. Mine's not puffing any smoke, exhaust is clear, but I have seen what looked like water drip from the tailpipe, but when I gave it the smell test, it was clearly gas... Either way, I replaced that sensor already, and the code is gone, but the issue remains... Link to comment Share on other sites More sharing options...
Adam Posted April 12, 2010 Author Share Posted April 12, 2010 Spoke to my dad about it, he's guessing cam or lifter... If it were a cam or lifter issue, wouldn't one of the cylinders not have compression, or have severely low compression? Link to comment Share on other sites More sharing options...
Indigent Posted April 12, 2010 Share Posted April 12, 2010 (edited) The coolant temp sensor is not in the valley on the VG30E. It is on the manifold for the upper radiator hose. It is the one with the yellow connector. The only thing in the valley for the VG30E is the knock sensor. Did you ever finish troubleshooting the ECU not having any lights? You need to look through the FSM and run each diagnostic mode. When you turn the ignition on, it automatically goes into mode 1, which is essentially the O2 sensor check. The green light basically indicates when the O2 sensor is regulating fuel ratio. If you don't get any lights at all, it is very likely that your ECU is in limp mode. When in limp mode, the fuel injector timing pattern is changed from sequential injection to simultaneous. That might explain the excess fuel you observed when pulling the plugs, and the running like crap. Also, the speed of the engine is limited in limp mode to make it extremely obvious to the driver that something is not right. Only two things can put the ECU into that failsafe mode, one is an internal ECU problem such as a majorly failed component, and the Camshaft Position Sensor not working. Verify that your ECU works as advertised and go from there. Having the Resistor and Capacitor go as you did is very strange in itself. Resistors don't just blow up for no reason. The resistor and capacitor are part of the circuit for the ignition coil and are driven by the ECU. If there was that much damage to the resistor and capacitor, I would say that your ECU got toasted. You also need to checkout the Power Transistor. The resistor regulates the power transistor. The power transistor controls the ignition coil. When that resistor blew, It may have overloaded that power transistor as well. So the things you need to check right now are: 1. Verify ECU operation. 2. Verify the Power Transistor is still OK. 3. Verify wiring from ECU connector to Resistor, Power Transistor, and Ignition Coil. Edited April 12, 2010 by Indigent Link to comment Share on other sites More sharing options...
Adam Posted April 12, 2010 Author Share Posted April 12, 2010 (edited) The coolant temp sensor is not in the valley on the VG30E. It is on the manifold for the upper radiator hose. It is the one with the yellow connector. The only thing in the valley for the VG30E is the knock sensor. Did you ever finish troubleshooting the ECU not having any lights? You need to look through the FSM and run each diagnostic mode. When you turn the ignition on, it automatically goes into mode 1, which is essentially the O2 sensor check. The green light basically indicates when the O2 sensor is regulating fuel ratio. If you don't get any lights at all, it is very likely that your ECU is in limp mode. When in limp mode, the fuel injector timing pattern is changed from sequential injection to simultaneous. That might explain the excess fuel you observed when pulling the plugs, and the running like crap. Also, the speed of the engine is limited in limp mode to make it extremely obvious to the driver that something is not right. Only two things can put the ECU into that failsafe mode, one is an internal ECU problem such as a majorly failed component, and the Camshaft Position Sensor not working. Verify that your ECU works as advertised and go from there. Having the Resistor and Capacitor go as you did is very strange in itself. Resistors don't just blow up for no reason. The resistor and capacitor are part of the circuit for the ignition coil and are driven by the ECU. If there was that much damage to the resistor and capacitor, I would say that your ECU got toasted. You also need to checkout the Power Transistor. The resistor regulates the power transistor. The power transistor controls the ignition coil. When that resistor blew, It may have overloaded that power transistor as well. So the things you need to check right now are: 1. Verify ECU operation. 2. Verify the Power Transistor is still OK. 3. Verify wiring from ECU connector to Resistor, Power Transistor, and Ignition Coil. Yes, ECU works fine, I pulled the trouble code 13 for the coolant temp sensor, now it's clear of codes since I resolved that. I'm taking the plug wires into Auto Zone tonight to have them continuity checked/resistance checked, so hopefully all is well there, but I kind of doubt it's them. I've already verified all the wiring is good, no more melted portions, it was all limited to under the hoot, the wiring behind the resistor/capacitor didn't melt, it was all the wire between the 4 connectors on the passenger side, and the ground wire going to the distributor that melted. There are no melted on the harness going into the ECU. Also, something that started working as soon as I replaced the resistor/capacitor was my fuel gauge, not sure if it's fully related, but when I got it back in 2006, the gas gauge wouldn't go up to full, it'd stop at 3/4, now it indicates full again. I've noticed while the engine is running, the green light goes off and on for about 5-10 seconds at a time, in regular intervals, is this normal operation for the ECU? I know the crank angle sensor works so much in the fact that it kicks on the fuel pump relay like it's supposed to when the rotor is under the #1 plug. Edited April 12, 2010 by Adam Link to comment Share on other sites More sharing options...
Indigent Posted April 12, 2010 Share Posted April 12, 2010 Did you electrically checkout the Power Transistor and Ignition Coil? With all of that melted wiring, I would imagine that the transistor and coil got messed up too. Also JFYI, the wire from the distributor goes directly to the "condenser" which is the capacitor. That is the reason that wire melted too. You might want to crack the case on your ecu, and see if anything in there got all melty. The three wires of concern at the ECU are 1,3,and 6. They go to the resistor and power transistor. Follow the traces from those three pins to wherever they end on the board and see if anything let out magic smoke. Also, you might go to the junkyard and pickup a transistor and an ignition coil. The power transistor is the grey thing behind the ignition coil on the plenum there. Link to comment Share on other sites More sharing options...
Adam Posted April 12, 2010 Author Share Posted April 12, 2010 (edited) Did you electrically checkout the Power Transistor and Ignition Coil? With all of that melted wiring, I would imagine that the transistor and coil got messed up too. Also JFYI, the wire from the distributor goes directly to the "condenser" which is the capacitor. That is the reason that wire melted too. You might want to crack the case on your ecu, and see if anything in there got all melty. The three wires of concern at the ECU are 1,3,and 6. They go to the resistor and power transistor. Follow the traces from those three pins to wherever they end on the board and see if anything let out magic smoke. Also, you might go to the junkyard and pickup a transistor and an ignition coil. The power transistor is the grey thing behind the ignition coil on the plenum there. I replaced the ignition coil already. I wouldn't be able to get to the boneyard to get a power transistor until the weekend because of my hours and the hours of the boneyard that has the 91 Pathfinder in it, and it's location... I opened the ECU so I could see the LED's more easily, was hard to see them in normal operation, the inside of the ECU is pristine. The wiring from the capacitor to the ignition coil didn't melt, it melted on the other side, from the 4 plugs on. The resistor portion of the resistor/capacitor actually stayed in tact, and those wires didn't melt at all, though I still replaced them with the rewire. I'll try to get the Power Transistor tested while I'm at Auto Zone tonight. Edited April 12, 2010 by Adam Link to comment Share on other sites More sharing options...
Adam Posted April 13, 2010 Author Share Posted April 13, 2010 I got the ignition control module tested, it failed every test but one on the Weller machine at Auto Zone... I just bucked up and replaced it, but it didn't resolve anything. Link to comment Share on other sites More sharing options...
Adam Posted April 13, 2010 Author Share Posted April 13, 2010 Any other ideas? I'm considering doing spark plugs, wires, and distributor this weekend... Link to comment Share on other sites More sharing options...
Kingman Posted April 13, 2010 Share Posted April 13, 2010 Aren't those already new? Link to comment Share on other sites More sharing options...
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