Engine fails to run in speed density
10-29-2012, 10:09 PM
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Engine fails to run in speed density 2000 Camaro with LQ9 bottom, L92 heads, LS3 intake, rails, injectors, 641/615 231/236 112, 1-7/8 LT, dual 3 inch, 92mm tb, wideband, hp tuners...
Car runs on stock LS1 tune. Corrected fuel injector rates and it runs even better yet, idles too. Set MAF high freq fail to 0, maf dtc's to 2-no mil light, getting ready to run speed density and tune VE tables. Once the MAF is disabled, the car fires but sputters and dies immediately. I must be missing something, because like I said earlier, it actually runs fairly well considering the mods on a stock tune (while on jack stands in the garage). I'd really like to get this thing to run in SD so I can start tuning it. Any input would be greatly appreciated. Thanks.
Car runs on stock LS1 tune. Corrected fuel injector rates and it runs even better yet, idles too. Set MAF high freq fail to 0, maf dtc's to 2-no mil light, getting ready to run speed density and tune VE tables. Once the MAF is disabled, the car fires but sputters and dies immediately. I must be missing something, because like I said earlier, it actually runs fairly well considering the mods on a stock tune (while on jack stands in the garage). I'd really like to get this thing to run in SD so I can start tuning it. Any input would be greatly appreciated. Thanks.
10-30-2012, 07:07 AM
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I didn't look at your tune, but make sure the DTCs for the MAF are set to MIL on first error. Verify it's throwing the code in the scanner. If it is, then you are in speed density. You have a 2000 operating system so there is a primary and a secondary VE table. Copy your primary over to the secondary if you haven't already. Then you're ready to start tuning in SD.
10-30-2012, 08:10 AM
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After a few hours of beating my head against the wall last night, I took a break for a minute. After taking another look at it, I found what was wrong. Turns out there was nothing wrong with the tune, everything was set up perfectly to run in SD. However after reviewing an earlier log file of the car actually running with the MAF still enabled, I found the MAP sensor reading to be the same at all times regardless of engine RPM. I started thinking about how this could be. I then realized that I put a LS3 MAP in, and started doing some research about the differences between LS1 and LS3 maps, and found they are totally different. A quick OS upgrade to 2 bar speed density, edited MAP scaler and offset, and away it it went. MAP started working properly and the car fired right up, in SD, ready to be tuned.
