Need help with Accel DFI
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Need help with Accel DFI I know it is off topic, but does anyone on here have any experience tuning the old original version of Accels DFI (I have version 6.32 I think) I am having a problem with TPS enrichment and need to talk to someone. This is on a regular SBC, not an LS1 based engine. Thanks in advance.
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Do you have too much or not enough enrichment? On the old Gen VI systems there are basically three things that affect accel enrichment, TPS, MAP and the fuel table. If you have added large injectors you require less. First, find out where you are at during idle and cruise on the base fuel map table. Then below them, as load increases below those points, make those numbers larger, experiment. Also experiment with your TPS accel enrichment table. I usually set the MAP enrichment table to zero, usually not needed and can cause too much fuel if rough idle and/or radical cam, can really confuse tuning. It's all in the combination of those two settings. I am not looking at a 6.32 program now so my terminology may differ from that. Hope this helps. EJ
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It was running decent until Thursday when I hooked up the wideband and drove it about 125 miles round trip. During the trip I worked on the base fuel tables trying to get 14 to 1 or so at cruise then no richer than 12 to 1 at other throttle positions. I got the numbers all decent but now it acts like a carb with the accelerator pump completely disconnected. It won't take any throttle without coughing and sputtering. It doesn't matter what I change the TPS tables to it doesn't seem to make any difference at all.
Am I going to have to adjust the base fuel table to where it will take gas smoothly? It will be way too rich everywhere else if I do that. This is a stock cammed HO 305 motor with a TPIS mini ram with an LT1 throttle body and injectors (24 lbs?) I am just trying to get a decent tune on it so I can sell the car.
Am I going to have to adjust the base fuel table to where it will take gas smoothly? It will be way too rich everywhere else if I do that. This is a stock cammed HO 305 motor with a TPIS mini ram with an LT1 throttle body and injectors (24 lbs?) I am just trying to get a decent tune on it so I can sell the car.
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Does this happen in all RPM ranges or just your initial low RPM tip-in? If it is just your intial tip-in, raising the fuel map numbers dramatically under your idle and near idle numbers should not cause your car to run rich. Your initial tip-in will go to these higher map numbers but quickly leave them as your RPM increases thus aiding your TPS acceleration enrichment. Is your TPS working or adjusted properly? One way to view this is to go to "idle" and "throttle follower" and see if the throttle indicator is at zero. I don't think that your LT1 throttle body TPS is adjustable but if it isn't, somehow this has to be addressed if incorrect. It's been awhile since I've done a Gen VI and do not have a program in front of me but I think in your "Global" setup, there is an item dealing with "ae" (acceleration enrichment}. I Can't remember what it's for so you may want to research this in your manual. We are overlooking something basic here because your combo should not be this difficult. If you had a 58mm throttle body, then it could be.
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I only had a few minutes to work on it today so I took your advice and richened it up a lot from the area where it idles on down the chart into the higher load areas. I got it better than it has ever been now. I think with a little more fine tuning it will be great.
Now on to the start and die on cold start.........It will start and run a few seconds then stall on cold starts. It does this about 3 time and then it is ok the rest of the day. I have adjusted the after start tables with no real effect. Any hints on this?
Now on to the start and die on cold start.........It will start and run a few seconds then stall on cold starts. It does this about 3 time and then it is ok the rest of the day. I have adjusted the after start tables with no real effect. Any hints on this?
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Originally Posted by dynocar
You probably need to message your fuel Vs ECT table in temp range that it is when you start it.
The AE tables (delta TPS vs AE factor) should've fixed the stumbles. I'm not sure why that wouldn't work, but increasing the numbers in the low RPM high load blocks seems to have helped you.
Your curve on the ECT vs enrichment factor was probably a little lazy in the cooler temp range too.
It just may be a case of your enrichment curves not being quite steep enough for the amount of fuel your injectors can deliver.
Some engines need really steep curves to deliver more fuel than you may think it needs. I prefer handling AE in the AE tables instead of on the base map.
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