Daeron Posted March 24, 2007 Share Posted March 24, 2007 Thanks braap for explaining that about the tps i didnt know u had to use the stock one cause i have seen people using the tps that came with the 60mm tb. I will put my stocker back on and adjust the timming to what u said 12-15. And do i keep the advance unpluged or just leave it hooked up? I also found that the vacume line from the canister came undone from the t/b to. Thanks again for taking time to explain that to me. If you are using the TPS that came with the 60mm TB, that IS your problem. There are two kinds of TPSs.. go find your EFI handbook (http://www.atlanticz.ca/zclub/techtips/efisystem/280zfuelinjectionbook.pdf) and look at what the TPS does. The Original Zcar TPS was two switches.. when the throttle was closed, one switch was closed indicating that you aren't pushing the pedal at all. When the throttle was ALL the way open (WOT, the OTHER switch closed, indicating WOT. When the throttle is somewhere between, neither switch is closed. In other words, the TPS can say three things.. Zero throttle, mild throttle, or full throttle. More Modern TPS units are potentiometers.. picture an old stereo volume knob linked to the throttle plate. as you open the throttle, this "pot" changes its internal resistance. The ECUs on these newere vehicles expect to send a signal voltage to that potentiometer, which then changes that voltage (the pot is a variable resistor) and the ECU reads the voltage and infers the throttle position.. In other words, the original TPS is a switch that can say one of three things, and the later TPSs are infinitely variable "volume knobs" instead.. so you are just confusing the ever-loving hell outta your ECU with this new TPS:tongue: You may as well be trying to use a MAF out of a 300ZX instead of your flapper-door AFM, just TOTALLY different technology. Good luck. Quote Link to comment Share on other sites More sharing options...
81280zx Posted March 25, 2007 Author Share Posted March 25, 2007 ok so far i unpluged the tps and now it runs ok but still does its thing at 4k but not as hard. could having the egr not hooked up cause it to do this? im also trying to still figure out the vacume lines but i have the canister and the disty hooked up and the fpr and there are no vacume leaks so far that i have found. Quote Link to comment Share on other sites More sharing options...
Daeron Posted March 25, 2007 Share Posted March 25, 2007 Well, you need a TPS to tell the computer where the throttle is.. you just need the RIGHT TPS. I don't know what the ECU would do, or how the engine would behave, without ANY TPS connected. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted March 25, 2007 Administrators Share Posted March 25, 2007 Without the OE TPS, at Wide Open Throttle, the engine would just run too lean. It will run and rev up, part throttle will act normal as the TPS doesn’t close the WOT switch till approx ¾ throttle application any how, but at WOT it will be so lean it will lean misfire, (pending the mixture was correct to begin with). Running it that lean for any extended periods is bad. End result is usually a burnt exhaust valve. The lean misfire is about the only drivability side affect you would notice with the TPS disconnected… Quote Link to comment Share on other sites More sharing options...
81280zx Posted March 26, 2007 Author Share Posted March 26, 2007 right now im trying to adapt the old tps to the new t/b so i havent ran it hard yet untill i get that all fixed and adjusted. I have noticed that with it disconected that it has a slight tremble at 4200 at wot but it clears up and then pulls hard. But i have adjusted the timming again so that may have made it better all around. But when im just getting up to speed it does fine except at wot so for now im just taking it easy till i fix the problem and it can break in better. Quote Link to comment Share on other sites More sharing options...
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