I need help, 435 hp street port, before I bought the car it was running a PowerFC Tuned by ELITE, we put the stock EC back and i have been running it like thatfor about 3 weeks, Suddenly it decided it was gonna start to run real lean, so lean that mostly is wont start, I replaced the fuel filter and checked the fuel pump, Fuel pressure is at 31psi. during idle, what can I do to make it run more rich or what should I check into?

 

435HP Street ported running on stock ecu?? and you wonder why you are running lean? What were you smoking when you replcae the PFC with the stock ecu.

 

wth?

 

Trust me the stock ECU is not the problem, its totally capable of handling my car, there must be something else, it has run perfect with the stock EC for 3 weeks...what else could it be?

 

Ignore it, this guy is just trying to **** everyone off...

Just so you don't think I'm being an *** about it, do some research on this forum, and you'll find the ECU swap back to stock is what killed your motor...

Richard

 

3 weeks? You consider that running fine? Do you have an A/F ratio meter? the stock ECU should be replaced after intake, dp, catback, and highflow cat/ midpipe. Are you running anything to supply more fuel (piggyback ecu) or anything? With that setup I would say the car would only last about 3 weeks...

 

lololol... im sorry but if you were trying to run a highly modded rx7 on a stock ecu then you are a COMPLETE MORON!!! i just solved your dilema

 

what I understand is that when you have an ECU with out power for a certain period of time it will go dormant and sort of blanket itself, after putting it back in it might need to "relearn" everything that is going on, but it shouldnt take 3 weeks to show signs that it isnt going to work, by running fine for 3 weeks after putting the stock ECU back in I mean it ran perfectly, everyday, for 3 weeks up until yesterday... The guys at ELITE that tuned my car said that it is something more simple than the stock ECU and it will be able to handle the car with the mods it has...

 

dood put the PFC back on!....the stock ECU on rx7's will not remap the fuel nor care about how modified ur cars is now...it will continue to run the stock fuel maps no matter what even if u bought a brand new ECU from mazda that has never been on anycar....So if u do want to keep the car alive put the PFC back on....

Now i have a question...Why the **** did u take off the PFC in the first place...that waz a very stupid move..

 

You are running lean because you put back the stock ECU. Unless you have some other forms of additional fuel controller, otherwise 435hp on the stock ECU is not healthy.

Timmy

 

ohh BTW whats ur setup?

 

why would it continuosly run nice and rich as it should for 3 weeks after installing the stock ECU?

 

I cant afford another power FC and Commander, what else is out their that would be good for a Street port, 3mm apex seals, intake, 31/4 dp and all the way back to an apexi n1 with pill ?

 

on top of all that, the engine isnt running any hotter than it should be, when it started to run lean it just didnt want to start very well, and the idle slowed like 200rpm's, but I havent noticed any change in temperature since its been running lean, I havent driven since its been in this condition but I have gotten it started and let it warm up and it will sit at a totally safe temp. while idling, i dunno know if it would heat up if I took it out and im not willing to find out... but that also seems odd to me that its not heating up running that lean

 

honestly i dont know....But trust me the stock ECU is to be run on STOCK cars....You can also look at maybe chipping the ECU...that could work if ur on a tight buget i guess...

 

well i havent really been exposed to leaned out rx7's...so i dunno what really happends but from what i know i dont see what leaning out has too do with overheating...But again im not exposed to leaning out rx7's....

 

There is nothing out there that will be cheaper than a PFC that will work with those mods. BTW, there is no way that setup will pull 435 hp at the wheels. If those are your only mods, I have serious doubts about it pulling that at the flywheel.

If you limited the car to 10 psi with a boost controller (if that's even possible with an intake and full exhaust), the stock ecu MIGHT run rich enough to be safe, although probably not with a streetport.

Again, why did you remove the PFC in the first place? It doesn't matter if you can afford it or not. You need an ecu as I wouldn't trust the car to be rich enough even limited to 10 psi. If you can't afford an ecu, A) you shouldn't have bought the car, B) you can't afford to replace the engine, which is likely headed to that great big rotor in the sky....

Understand we are not flaming you, just trying to make you see the light.

 

all i can say is haha what a dumbass noob.umm first of all if the shop told u that they need to be put of business.second of all why would u pull hte pfc out?next why r u gonna tell us thats not what it is when we r experiemced at this?isnt this why u came here is find out from experienced owners what u diagnosis is?r u still in high school?ur ecu when ever ur car is modded other than intake pulleys downpipe and catbike is only good for startup anything after that is stupid.u cant afford a power fc right now?well guess what now u cant afford an engine rebuild either.haha listen to what we got to tell u.

 

Im not the type of person to sit and list all my mods, personallyi have the dyno sheets and I know all my mods, and "flaming" me as you are isnt going to help any, all I needed was some advice, so if all you can tell me is I need a new ECU, maybe you could tell me what would be preferred by you "experts" as I said before the Power FC and Commander is a beautiful piece but I cannot afford another...

 

Stock ECU ? How many Psi's of boost are you running ?

 

12-13...

 

Are you reading our posts? If you have dyno results, what are your A/F readings across the rpm range? They should be around 11.5 with a maximum of 11.8 or so (even that is pushing it). Again, why did you remove the PFC in the first place? Also, the shop you are going to sounds ignorant of FD tuning techniques. We're just trying to help. Ignore the flaming from some posts and actually read some of the info here.


Edit: As I and others have posted, 10 psi is the absolute max you can run on the stock ecu with those mods.

 

twintriangles,

You state that the stock ECU is running so LEAN that the car won't even start? This is not true. The stock ECU should be able to start and idle no matter how modded your car is. Running lean as referred to on this forum never refers to the idle mixture. It is always in regards to the air/fuel ratio under boost.

If your car won't start then you have another problem and it isn't related to the ECU or the fuel filter. I clogged filter would still be able to let the car idle, there is hardly any fuel requirements at idle. When adding boost the clogged filter, low fuel pressure problem will show up.

Jeff

 

The car was tuned on the dyno at ELITE and it put out that power with the PowerFC, Eventually I will crack and buy a new ECU but for now I feel that because it ran for 3 weeks with the stock ECU that it must be a more simple explanation (stock fuel regulator?)

 

Again, what would be an acceptable ECU to get for a car outting that much power, Keeping in mind my budget and that I cannot afford another PowerFC even though it was an extremely cool toy...;-(