badjuju Posted April 25, 2010 Share Posted April 25, 2010 Here we go: Straight six, wasted spark on a 7mgte, 6+2 config on Vems, problem happens with firmware 1.0.73, and firmware 1.1.70. I foul my plugs in about 10 min of running, due to running pig rich. Plugs 2 and 5 are never discolored, simply covered in fuel. Plugs 1,3,4, and 6, are so fouled you could paint with them. Injectors are getting signal, my LED fires right up when cranking. Coil packs are getting signal, my LED fires right up when cranking. Spark plugs are firing, I get spark from all 6 plug wires. I thought maybe the coil handling 2 and 5 was only firing intermittently or something, so I replaced it (I have 6 spares ). Did not help. I thought maybe I had connected my coil to a logic driver instead of a big boy driver. My rational behind this was that just because I get a spark, doesn't mean it's intense enough. I pulled wires 5 and 6 to compare their spark intensity (seemed the right thing to do), and they seem to be equal with any other spark from a running motor. I noticed today that plugs 2 and 5, when I pulled them, had a little black, as if they were firing, but there was no soot. To me, this means that the plug is firing, the injector is firing, the cyl is getting fuel, since the plug is covered in it, but it's not exploding and causing soot. WTF is going on? Bent valves maybe? It seems like the most logical choice to me so far. Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 25, 2010 Author Share Posted April 25, 2010 Quick note, I posted this here because I'm looking for a general tech answer, not a vems specific, not a 7mgte specific, etc.. I figured this would be the right place for it. Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 28, 2010 Author Share Posted April 28, 2010 Sweet, 70 views and no replies. Thanks for your input. I know someone has some idea as to what they think this might be, and that's all that I'm asking for. Nut up and state your opinion. Quote Link to comment Share on other sites More sharing options...
woldson Posted April 28, 2010 Share Posted April 28, 2010 Wiper fluid may be low? How is that? Quote Link to comment Share on other sites More sharing options...
FlatBlack Posted April 28, 2010 Share Posted April 28, 2010 (edited) Sweet, 70 views and no replies. Thanks for your input. I know someone has some idea as to what they think this might be, and that's all that I'm asking for. Nut up and state your opinion. Injectors, fuel pressure, fuel filter, FPR? Do you have a wideband? Does the car idle? I'm forwarding this to my roommate who owns a MKIII with a 7M GT-E. Edited April 28, 2010 by flatblack280 Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 28, 2010 Author Share Posted April 28, 2010 Injectors, fuel pressure, fuel filter, FPR? Do you have a wideband? Does the car idle? I'm forwarding this to my roommate who owns a MKIII with a 7M GT-E. Injectors are 440 cc\min, stock 7mgte injectors. Fuel pressure is there, but I don't have a gauge. Fuel filter is off an l28et. FPR is the stock one from a 7mgte. Wideband is down; haven't gotten it to communicate with VEMS yet. Car idles fine. It'll drive up and down the street. I'd really appreciate that flat, I've got this sitting on three forums, kind of consolidating answers at the moment. Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 28, 2010 Author Share Posted April 28, 2010 Wiper fluid may be low? How is that? Topped if off, didn't help. Quote Link to comment Share on other sites More sharing options...
johnc Posted April 28, 2010 Share Posted April 28, 2010 Nut up and state your opinion. I did when I changed the title to your post. Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 28, 2010 Author Share Posted April 28, 2010 Good Job, John. Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 28, 2010 Author Share Posted April 28, 2010 Before I purchased the motor, I tested the compression. After installing a cometic mls gasket and reinstalling the arp studs the previous owner messed up, and forgetting to tighten the timing belt tensioner, and cranking the engine for a while, and realizing what I had done, and setting the timing correctly and tightening the damn tensioner, I got it to start and run and all that, then noticed the spark plug issue, see post #1. Anyhow, I thought I'd run the compression test again, hoping to find that 2 and 4 were extremely low, thus telling me what my problem was. Anyhow, here are my numbers... 2 and 4 are lower than the rest, but I'm not experienced enough to know if they're low enough to justify calling the valves bent or not seating. tell me what you think: Pre Purchase: 135 133 137 148 125 155 Just now: 151 143 151 160 145 155 Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 28, 2010 Author Share Posted April 28, 2010 allllllso... I just ran an LED to each coil pack, and it seems to be firing left middle right, rather than left right middle, which is what I, and VEMS were under the impression it was firing. Super duper. I'm thinking maybe cyl 2 and 5 are a little lower than the rest, not because the valves aren't sitting, but rather because I'm washing the piston rings with fuel. Thoughts? Quote Link to comment Share on other sites More sharing options...
johnc Posted April 28, 2010 Share Posted April 28, 2010 I foul my plugs in about 10 min of running, due to running pig rich. This is your base problem. Get the FSM and do a basic fuel system diagnosis and troubleshoot. Also, get this book: http://www.amazon.com/Bosch-Fuel-Injection-Engine-Management/dp/0837603005 Quote Link to comment Share on other sites More sharing options...
badjuju Posted April 29, 2010 Author Share Posted April 29, 2010 I'll buy the book, looks good. I know it's too rich, I think the base problem is that only two of my three coils are going to a useful spark. BUT it appears I've fixed that, the firing order was off. Weird, it's the same thing that happened to my buddy's VEMS setup. Next up is getting my wideband to communicate, then driving it until the wheels fall off. John, I appreciate the input. I also appreciate the humor in your thread name change, lol Quote Link to comment Share on other sites More sharing options...
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