AtlantaZ Posted June 6, 2011 Author Share Posted June 6, 2011 Alas, I have run out of ideas. It only wants to idle when I set the Injector Characteristics to 75% current limit and time threshold to 25.4ms, even though they're low impedance injectors. And the only way I can even get it to 2000rpm is by feathering the gas, with a lot of backfiring. Here's what I know so far: Timing - Megasquirt shows 17* commanded at idle, timing light shows same. Spark - Sparking. Timing light reads current on every spark plug wire, and the engine runs. Sort of. So there's sparking in there. Fuel - Good. Aeromotive FPR shows 45psi at idle, creeping up to about 48 when the engine throttles up. Injectors - Injecting. Tunerstudio injector test mode has all six injectors clicking away. Signals: RPM - Good. 36-1 toothed wheel on an EDIS VR sensor. Good RPM reading in Tunerstudio. Coolant/Inlet Air Temp - Good. Using standard GM sensors. At cold start, readings match ambient air temp. Coolant temp climbs up to normal operating temp (190), then holds there. Manifold Absolute Pressure - About 80-88 at idle. When I throttle it up to 2000rpm, pressure climbs to about 120kPa (due to turbo). Using stock Megasquirt onboard MAP sensor, reading from vacuum line that originates at intake manifold. AFR - Innovate LC-1 shows about 15:1 at idle in Tunerstudio. I may check cylinder compression tomorrow just to see if there are any issues there, but I don't see any oil vapor blowing out of my PCV hoses. At this point, I think it may be one of the following: Injector driver circuitry on Megasquirt is bad One or more injectors isn't operating correctly Vacuum leak on intake manifold Ignition driver (BIP373) is faulty EDIS ignition module or coil pack is faulty Possessed by one or more demons Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 6, 2011 Author Share Posted June 6, 2011 Car is now in jail at the auto shop. Will let you guys know when I hear news. Quote Link to comment Share on other sites More sharing options...
rwdawg2 Posted June 10, 2011 Share Posted June 10, 2011 Again keep me up to date. I'd like to come down and talk to you and see your car once you get it back. I work in Gainesville so I'm just up the road from you. Good luck Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 10, 2011 Author Share Posted June 10, 2011 Shop called today and said that the RPM signal output is intermittent. Diagnosis ongoing. Could be a bad ground, bad sensor, etc... Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 15, 2011 Author Share Posted June 15, 2011 Update - VR sensor mount had a little play in it. Shop applied Loctite and reattached - RPM signal is now good. Everything looks mechanically sound. I think that means we're down to an electrical/electronic problem. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted June 15, 2011 Share Posted June 15, 2011 Manifold Absolute Pressure - About 80-88 at idle. When I throttle it up to 2000rpm, pressure climbs to about 120kPa (due to turbo). That doesn't make sense to me. A couple things about that statement don't add up. I assume you are revving the engine to 2000rpm while setting in neutral? If so, then it is highly unlikely the turbo builds any boost, even a couple pounds. Idle at 80-88kpa is way off from anything I have experienced. I am thinking your MAP sensor is wrong, installed wrong, damaged or using the wrong settings. I did not read over the thread again so this has probably all been mentioned before. It will be interesting to see what the shop figures out. Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 15, 2011 Author Share Posted June 15, 2011 I agree that something is definitely off with the MAP reading. It is reading 97 with the engine off, so the baseline calibration looks okay. It seems to react normally when I test it, but I'm not using precision vacuum test instruments. The guys at DIYAutotune thought that other variables in the setup might be causing the engine to run poorly and therefore drawing insufficient vacuum. I'm almost certain that my ECU has the stock MPX4250 - but it's worth rechecking! Regarding spool-up... I was told that I could expect my GT3071r turbo to start spooling in the early 2k RPM range, with full spin by about 3200rpm. So I wasn't put off by the mild positive pressure reading... but again, something worth checking. I can definitely hear the turbo winding down when I shut the engine off, so maybe it's moving at least a little air? Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 15, 2011 Author Share Posted June 15, 2011 Update #2 - Shop is now analyzing my tune. Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 15, 2011 Author Share Posted June 15, 2011 Update - Megasquirt board is faulty!!! Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 16, 2011 Author Share Posted June 16, 2011 May replace ECU with MS3 or MS3X... thoughts? Or better yet, donations? Would it be worthwhile to have another MS3/EDIS install documented on Hybridz? Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 16, 2011 Author Share Posted June 16, 2011 Clarification: shop reports faulty RELAY BOARD, not ECU. Slight difference there! Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted June 16, 2011 Share Posted June 16, 2011 Reason it was spooling appeared to have been a couple plug wires switched, lighting off the mixture in the exhaust. It also had a fuel leak and wasn't holding fuel pressure. Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 16, 2011 Author Share Posted June 16, 2011 You forgot to mention that the fuel was leaking directly under the blue flames spouting out of the wastegate discharge. Or maybe you withheld that so as to not make me look bad... Matt, did you have a chance to see/hear the engine run smoothly yet? Or are we still waiting on the relay board replacement? Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted June 17, 2011 Share Posted June 17, 2011 (edited) I only check up on the car when the mechanic runs into things he's not sure how to deal with (it's at a shop down the road from DIYAutoTune). Didn't hear any news yesterday. Edited June 17, 2011 by Matt Cramer Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 23, 2011 Author Share Posted June 23, 2011 Shop reports that everything is now wired correctly, but that the engine still isn't driveable. They think that there's a problem with the tune. Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 24, 2011 Author Share Posted June 24, 2011 I went by the shop and checked on the car. We're still perplexed... the AFRs are reading in the 12-14 range, but the engine is running very, very hot (glowing manifold) and it still won't rev past 2500RPM! The turbo is also spooling up at about 1500rpm. I'm wondering if maybe my timing table isn't advancing enough? Quote Link to comment Share on other sites More sharing options...
mobythevan Posted June 24, 2011 Share Posted June 24, 2011 Sounds like what Tony D. experienced when messing with the 81 CAS and his timing was far off which was burning the mixture as it leaves the cylinder. Good anti-lag setup. Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 24, 2011 Author Share Posted June 24, 2011 I think that may be the case for me as well. I wonder how many degrees off he was? Is 5-10 degrees of timing offset enough to take it from barely idling to rocking-and-rolling? I agree that the anti lag part is awesome, until I smell my downpipe wrap burning and my coolant temps get about 230F! Quote Link to comment Share on other sites More sharing options...
Leon Posted June 25, 2011 Share Posted June 25, 2011 Has anyone bothered to hook up a timing light and check actual timing? Quote Link to comment Share on other sites More sharing options...
AtlantaZ Posted June 25, 2011 Author Share Posted June 25, 2011 Yes - the shop reported that timing appeared to read correctly. It's about to get a more comprehensive workover by a tuner. Quote Link to comment Share on other sites More sharing options...
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