Something's WAY off. Request for some eyes on my .MSQ
01-10-2009, 04:42 PM
#21
Pat et. al. -
I tried Pat's fuel map without much difference. Thanks for the effort. BUT...
I have made a huge discovery. Injectors on cyls. 3 and 4 (closest to firewall) are not firing at all! I used a home-brewed probe stethoscope and all four injectors click away happily on the stock ECU. Only 1 and 2 do on the MS. This explains everything. The leanness, lumpiness, etc.
I've troubleshooted the following:
1. Harness. My injectors are wired in the harness the exact same way as the DIY build doc in the Sticky threads. I have good continuity between the two ECU side injector ins and the four DB37 outs, spit of-course.
2. Using the Stim, I am able to get a good fuel injector led flash on both INJ1 and INJ2 pins. The problem with this is you can't discretely test all four DB37 outs. So I opened up the MS box and...
3. Measured voltage between Pins 32 through 35 and ground. I get a steady 3.2v at all four.
I'm now stumped.
I tried Pat's fuel map without much difference. Thanks for the effort. BUT...
I have made a huge discovery. Injectors on cyls. 3 and 4 (closest to firewall) are not firing at all! I used a home-brewed probe stethoscope and all four injectors click away happily on the stock ECU. Only 1 and 2 do on the MS. This explains everything. The leanness, lumpiness, etc.
I've troubleshooted the following:
1. Harness. My injectors are wired in the harness the exact same way as the DIY build doc in the Sticky threads. I have good continuity between the two ECU side injector ins and the four DB37 outs, spit of-course.
2. Using the Stim, I am able to get a good fuel injector led flash on both INJ1 and INJ2 pins. The problem with this is you can't discretely test all four DB37 outs. So I opened up the MS box and...
3. Measured voltage between Pins 32 through 35 and ground. I get a steady 3.2v at all four.
I'm now stumped.
Is your car a California car? I gots a feeling it is. (you know you could put your location in your profile....) I think they had the four-wires-one-for-each-fuel-injector going on in that year for sequential injection to meet emmisions crap. You mention four DB37 outs... What are you talking about? It only has two outputs for fuel injectors. Each driver fires a PAIR of fuel injectors.
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01-10-2009, 05:31 PM
#22
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Winner! Winner! Chicken Dinner!
thebeerbaron phoned me a few minutes after I posted postulating what turns out to likely be a 'California' car. I have wires on 2Y and 2Z, which according to my Wiring Diagram book should be unused.
I'm watching football now, but I'll get some time to add the extra pins in later tonight.
By four DB37 outs I simply meant that four of the DB37 pins are used for the fuel injectors.
thebeerbaron phoned me a few minutes after I posted postulating what turns out to likely be a 'California' car. I have wires on 2Y and 2Z, which according to my Wiring Diagram book should be unused.
I'm watching football now, but I'll get some time to add the extra pins in later tonight.
By four DB37 outs I simply meant that four of the DB37 pins are used for the fuel injectors.
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01-12-2009, 07:37 AM
#23
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Got a chance to drive it around a bunch yesterday. Runs like a top. The JAW even works! With Megalogviewer's help, it's running smoother and smoother each drive. Thanks to everyone for their help/suggestions!
There are only a few outstanding issues. It's prone to after-fires on lift then slight throttle application and it idles at about 1600. Trivial issues compared to what I was struggling with earlier.
There are only a few outstanding issues. It's prone to after-fires on lift then slight throttle application and it idles at about 1600. Trivial issues compared to what I was struggling with earlier.
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