Stock 94" TT going 15g, 550cc, flashed 98' VR4 ECU build.

[Drummer]

My stock 94 TT is getting 15g's, 550cc RC injectors, walbro 341 pump, BlackStealth EBC/logger, tanabe turbo back, Innovate WB02, Greddy S BOV, MSD wires, NGK 7 coppers, 3SX fuel pressure guage, full vac reduction w/all deletes, open air filter, 98 VR4 ECU, ACT clutch (installed already), and perhaps a thing or 2 more. All of the parts above I have. May go with an FMIC at the end. I will be doing it in stages, to make sure that each step works before proceeding. Im sure I will run into some kind of trouble, any help appreciated!!

PS This will be a street car, on 94 octane pump gas. I will be keeping the stock MAF, as I dont plan on going over 450hp.

[Drummer]

STAGE 1 : PLUGS, INJECTORS, FUEL GUAGE AND 98 ECU w/ADAPTER HARNESS

Did this today and the car fired up on first crank. I got a CEL about 30 seconds later, dont have the reader ready yet. The purge solonoid went nuts clicking. Car ran fine as far as I can tell. A few pulls, all good. Fuel pressure at idle was about 35-38psi. Engine mounted guage so I cant see it while driving (yet). Dont know why the purge solonoid went nuts, Im assuming that the 98 ECU sees things a little strangely on my 94 engine. The flash on my ECU is set up for 550cc's, but maybe not correctly for my 02 sensors, dunno.

[Boost4VR4]

You need a MAP for the 98 ECU as it's looking for it. Swap your Plenum with a 98 plenum and put the stock MAP sensor on the plenum and wire it in.

[Drummer]

I will simply disable the MAP in my flash file and reflash, if I can. I also have to find out the differences o2 sensors, if there are more on the 99 (its a 99 flash) then I need to disable ones that are not on my car. Would the missing MAP sensor make my purge solonoid go nuts on and off? It seems to cycle, and speed up with RPM. I unplugged it and drove with no ill effect that I noticed. I also need to root out anything in the 99 flash that does not pertain to my car. I will get this sorted out in short order, as there are a few members that are miles ahead of me like greg and aaron. Im not sure how far along these guys are, its been a while since ive been around. Im going to pull the CEL tonight with blackstealths logger and post here. I am also working to tweak the flash, already bumped the RPM to 800 at idle, and scaled the injectors to 550cc. I will be disabling all to do with the vacuum reduction (EGR etc.) Want to get rid of all the useless stuff in the engine bay.

[NOMIEZVR4]

great stuff man...keep us posted on the results...is blackstealth making harnesses? I'm also on the lookout for a 98-99 VR4 ecu...keep me posted if you find one for sale please. Thanks

[Drummer]

Blackstealth is not making them as far as I know (you can message him to ask), as these are being made by others as a package, and the market is rightly theirs for their work on the 3000gt file for ECUflash. Im not sure if they have the 98-99 VR4 ECU, but they have other ECU's modded to work. I wanted a 98 VR4 ECU so I got one. VERY VERY hard to find. 500$ mininum usually. If I see one I will let you know. Set up your ebay auto searches to find key words, like vr4 ECU, part numbers etc. One pops up here and there.

For those who are wondering what you need to do this, you need a 98-99 VR4 ECU or a modded ecu from other cars, a wire harness adapter to plug the new ECU to your cars harness, a tactrix 2.0 flash cable with mitsu adapter, ECUflash software (free at tactrix.com), the 3000gt rommeta file for ECUflash to be able to read a 3000gt file (this is where the real brainy work is being done, getting this file updated), and of course a stock 99 VR4 file that you will be modding to suit your car. Im not sure, but Greg E and the boys may have kits for sale, they were on their way, but I havent spoken with them for a while. They were working on a sweet kit, maybe its ready? Again, Im not sure where that went....

Anyway, the flashed ECU way of tuning is great, clean, and with a good EBC/logger, can get you running smooth.

[Drummer]

Read the CEL codes with the blackstealth logger. My car (Canada, FED emissions) Has only 2 heated O2 sensors, and the 99 flash looks for 4. Also, my EVAP system purge solonoid is goin nuts on/off when it never did before, so I unplugged it and im getting CEL for that too. I need to get the newest 3000gt file for ECUflash, as mine is old and I think the brainy boys have more things figured out and named in ECUflash. Im also getting strange trims... the logger reads a low/mid/high, and my low trims are at 50 at idle and coasting, at 120 on acceleration. Not sure what that means, but my o2's are coding like crazy, when there were no codes at stock. Here are the codes I have read so far :

P0155 - o2 heater circuit malfunction Bank 2 sensor 1 (need to disable, not on my 94)
P0156 - o2 circuit malfunction Bank 2 sensor 2 (need to disable, not on my 94)
P0161 - o2 heater circuit malfunction Bank 2 sensor 2 (need to disable, not on my 94)
P0135 - o2 heater circuit malfunction Bank 1 sensor 1 (did not throw a code using stock ECU)
P0136 - o2 circuit malfunction Bank 1 sensor 2 (did not throw a code using stock ECU)
P0141 - o2 heater circuit malfunction Bank 1 sensor 2 (did not throw a code using stock ECU)
P0443 - EVAP purge control valve circuit (unplugged, solonoid was going nuts on/off, didnt do that with my stock ECU)
P0446 - EVAP vent control circuit malfunction (related to unplugging the solonoid also?)
P1104 - Turbo wastegate solonoid - this is removed from the car, I am using an EBS. Need to turn off in the flash if I can.

There are a few things I have yet to learn about the differences between the 99 flash file I am using and the 94 car Im using it in. Any insight would be greatly appreciated! To be continued...

[Drummer]

Cleared the codes, pulled the neg battery terminal and plugged in the purge solonoid back in. No CEL, a couple codes gone for the purge, but rest are still there.

[GTOJOE]

What does the purge solonoid do?

[Drummer]

Its part of the EVAC system that recirculates gas fumes from the tank to the intake.