jpldude Posted January 27, 2006 Share Posted January 27, 2006 hi, I have a 260Z that i am currently running megasquirt and spark and a t3/t4 turbo and all the neccessary support components and i have also just installed a broadband o2 sensor and the car runs and drives smoothly. It appears to be running rich all the time and the boost seems to be coming in rather late and when it does come it doesn't seem to be producing the type of power I was expecting. So, I guess what I'm asking for is some methodology/precedures that will aide me in tuning my vehicle and getting some more power out of it. thank you in advance for help. Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted January 27, 2006 Share Posted January 27, 2006 a broadband O2 sensor? lol.. you mean wide-band?? How to Tune MegaSquirt whoo hoo Quote Link to comment Share on other sites More sharing options...
mobythevan Posted January 27, 2006 Share Posted January 27, 2006 what numbers is the wideband sensor showing at different points in the VE table. You really have to drive the car in different gears at different loads so that you move all over in the ve table and check the AFRs at each point using the wideband(if you are tuning manually). Works great to have someone else drive the car while you tune the VEs. Quote Link to comment Share on other sites More sharing options...
zguy36 Posted January 27, 2006 Share Posted January 27, 2006 You say it is running rich.... so lean it out some. Too much fuel isn't good everywhere. Give us some numbers so we can see what you are looking at. -jeremy- Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 9, 2006 Author Share Posted February 9, 2006 How to Tune MegaSquirt whoo hoo Yeah I have read this about a dozen time and unfortunately still get lost. Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 9, 2006 Author Share Posted February 9, 2006 what numbers is the wideband sensor showing at different points in the VE table. You really have to drive the car in different gears at different loads so that you move all over in the ve table and check the AFRs at each point using the wideband(if you are tuning manually). Works great to have someone else drive the car while you tune the VEs. Moby, So I am pretty sure my injectors are 300 cc/min and I am running a setup more or less based on your sticky. Should I be running decent from your example VE, Spark, constansts, etc? If my injectors are 300 cc/min are they the same as the stock ones? (Please bear with me this is one of the few areas I am not entirely sure about, I do understand most everything going on in the system) Also, can someone please confirm if the wideband O2 sensor should be sorta jumping around all the time? I would have thought that they would filter the output from it to give a more steady reading for easier understanding. Anyone who can comment on any of this I would really appreciate it. Even more exciting is if there is someone with experience in the LA area that can help me tune. thanks for any help. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted February 9, 2006 Share Posted February 9, 2006 If my injectors are 300 cc/min are they the same as the stock ones? No, the stock injectors are smaller than that, I don't remember exactly what they are. The wideband will move around a little. At idle I would see it hitting like 13.1 then up to 13.6 or 7 then in the middle some where. You want it to update as fast as possible. The idea being that the ecu uses the fast update rate to correct fuel input if the ecu supports closed loop wideband operation. To get started tune for like 13:1 at idle, 14:1 at light throttle and 12:1 under load. If your cruising at 55mph it should read around 14:1 Then you floor it, it should immediately go to 12:1 and stay there until you back off the throttle. Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 12, 2006 Author Share Posted February 12, 2006 I went out to tune last night on a relatively flat stretch of highway, but I came up against something that I could use some help on. I can tune it just fine as long as I keep my foot out of it and it never boosts. As soon as we get a couple pounds of boost it goes way lean and even tho the injector opening time is goes up alot. So I was thinking that I may have messed up somewhere in my setup. Specifically, I think I have a stock NA FI fuel pressure regulator ( the silver thing on the fuel rail ). Would it dramatically cut fuel pressure under boost? Should I have found one off a turbo car or something? thanks for any input. Quote Link to comment Share on other sites More sharing options...
vashonz Posted February 13, 2006 Share Posted February 13, 2006 I don't know about the NA FPR. BUT, the turbo regulator is referenced off the manifold pressure, ie as manifold pressure goes up, so does fuel pressure, you should get a fuel pressure gage and see where it starts at, and what happens when it starts boosting. Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 13, 2006 Author Share Posted February 13, 2006 So it doesn't seem like the fuel pressure regulator would cause the sort of problem I am experiencing. Does anyone know why I would suddenly have fuel supply problems when I start boosting...even at just a couple pounds. The fuel pump is out of a 280zx turbo. Quote Link to comment Share on other sites More sharing options...
Xander Posted February 14, 2006 Share Posted February 14, 2006 Hi. I am using the same setup as you. A megasquirt (v3) and I use a techedge WB O2 sensor. What version of megasquirt are you using? I am on MS&S-E. You say that the AFR is jumping around a lot. Maybe you are not using it right. Are you using a linear output of the WB-sensor. I onces accidentally wired it up to the simulated narrowband output and it had the same symptoms as you discribe. Also in MS&S-E you can just set your target AFR table and let te EGO correction handle the tuning for you (within limmits of course). I use a stock bosch style fuel regulator. it will handle the higher intake pressure without a problem. you should hookup a fuel pressure gauge and have a look. You can buy them pretty cheaply of ebay. good luck the Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted February 15, 2006 Share Posted February 15, 2006 Xander.. you have a MSQ file I can peak at?? I'd love to see your setup with MSnS E Quote Link to comment Share on other sites More sharing options...
Xander Posted February 16, 2006 Share Posted February 16, 2006 sorry prox, I had laptop meltdown and all my settings are gone now. the car still runs and I am going to use my new laptop to download all my settings from the MS unit itself. But because I have a new laptop it does not have the required RS232 serial port. I am now waiting for my PCMCIA to RS232 adapter. apparently that is the best option to communicate with the MS unit. When it is up and running I will post the msq file but it could be a couple of weeks. I'll let you know how it all turns out. Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 18, 2006 Author Share Posted February 18, 2006 alright. I bought a fuel pressure guage and installed it. When we hit about 3lbs of boost the pressure drops from around 38psi to 17psi. Any idea what might cause this sort of thing? I remember reading something about the fuel feed and return line setup. I was just using the original pipes. Would this cause these sorts of symptoms? Also, how can I test if my used 280zx turbo fuel pump is not working properly? Quote Link to comment Share on other sites More sharing options...
woldson Posted February 18, 2006 Share Posted February 18, 2006 i know this is dumb, but cheack your fuel filter, that or maby you fuel pump cant keep up cuse old? Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 18, 2006 Author Share Posted February 18, 2006 checked the fuel filter and it is clear. It seems like it must either be either the fuel lines or the fuel pump. any comments on how I can effectively test these parts with the least effort/complicated setup. Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 18, 2006 Author Share Posted February 18, 2006 What is involved in moving from MS&Spark to MS&Spark Extra? Just curious. Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted February 19, 2006 Share Posted February 19, 2006 firmwire upgrade.. (software) thats it Quote Link to comment Share on other sites More sharing options...
jpldude Posted February 21, 2006 Author Share Posted February 21, 2006 So I replaced the fuel pump as I was losing pressure under boost. Now the pressure is good. But the waste gate actuator does not seem to be working. The boost just ramps up even tho I have my manual boost controller set to what should be basically no boost. If I remove the actuator how would you recommend testing it? Also, what sort of mileage do you think I can expect? Also, if the EGO correction is running then at boost what keeps it from pushing the AFR back to 14:1 after a few seconds? Quote Link to comment Share on other sites More sharing options...
mobythevan Posted February 21, 2006 Share Posted February 21, 2006 make sure you can open the wastegate lever by hand once you remove the rod from the vacuum canister. Mine was stuck. It should easily swing open and shut. Quote Link to comment Share on other sites More sharing options...
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