PCM sometimes pulls timing but can't for what reason. 1999 trans am running speed density sometimes the car will pull timing but can't find any reason why it should. I've been told that I should have my low and high octane tables the same. Also have heard there are calculations and tables not seen that affect timing. Any thoughts? |
It could be tons of things, post the tune I'll check the most common things. |
Burst knock??? |
mines doing something similar... it gets burst knock when ever i launch the car, in turn it pulls the same amount of knock retard which pulls timing. |
ive maxed the burst knock enable and zero'd the burst knock retard vs ect but i still pick up burst knock on the scanner |
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theres other things that factor into over all timing.. check your iat timing tables? |
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Torque management, traction control, IAT table, ECT table, commanded AFR table... Is it running off just the low octane table? |
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Is it an automatic? When you are able to post the tune and a scan there will be more chance of folks helping you. |
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System > General > System Options > BrakeTqMgt make sure that is a zero Transmission > Torque Management disable abuse mode and zero out all torque reduction tables Engine > Torque Management > General of course zero (or max out) tables that have anything to do with limiting torque That's about all I can come up with off the top of my head without seeing your tune. |
I was tracing this issue on a car once and I made a custom scanner in the hpt that monitored all timing functions. If you do that, you should be able to see where it is coming from. |
Post the tune |
1 Attachment(s) here's the tune. you'll notice how much timing I run in the "drive" table, it's for having the car on the transbrake. |
Post the details on your setup, what are all your mods? |
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390/ 4L80e billet 83mm turbo 14lbs boost, I run 50% 114 race gas 80lb injectors 4000lb car runs 143mph. |
You still run a MAF? (nevermind I see you don't) VE table looks bonkers. Injector data, Engine Size, Cylinder Vol looks wrong. Injectors will not flow the same volume when intake vacuum changes and it uses the Cylinder Vol to calculate along with your injector data for the VE table. VE table should look like a dyno sheet and not the ocean. Why is Boost Enrichment Enabled at 110 kPa but is set to 1.00 all the way across? I know it will use your PE EQ ratio table as it's richer. I know this doesn't help your problem but I wouldn't go into PE until you address those issues. Do you use a wideband? If so go drive around and get a log and post it up. Try putting the MAF codes to 2 instead of 3. Maybe your car is different but when I put mine to 3 the car will not run right. |
no maf, boost referenced fuel regulator. |
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