DSMchip And EPROM ECU

[WHITE GST]

I just installed a stage 3 chip and an EPROM ECU in my car also a set of FIC 750cc injectors, Well everything works good until I hit about 15psi then the car starts backfiring and loosing power, I did change the plug wires just like Jeff told me to, would I be running rich but the chip was burnt for those injectors?

I thought it was a boost leak but I did a test and I only have a real small one by the throttle body. The only thing I can think of is maybe because I have not mounted the EPROM ECU where the other one was, it's just hanging on the side of the kick panel. Does the ECU needs some kind of ground to work properly?

Also my A/F ratio gauge goes all the way to the lean side so I don't know. My stock boost gauge it's not moving at all so I'm not getting any knock either.

Any help would be well appreciated

 

[WHITE GST]

Could it be my spark plugs or wires ?

 

[KiNg MaRtY]

If you can get a wideband hooked up to make sure that either you are not running lean or too rich to the point that you are bogging. Could also possibly be a loose intercooler pipe

 

[95grntsi]

I would mount the ecu the way it is supposed to be. If its in there bouncing around, you could damage it very easily, but I dont think thats causing your misfire. What are all the specs burned on the chip? What fuel pressure did you tell Jeff when you ordered? Also if your mod list in your profile is up to date, you may want to think about getting a new fuel pump, the stocker doesnt really like a lot of boost.

 

[WHITE GST]

I would mount the ecu the way it is supposed to be. If its in there bouncing around, you could damage it very easily, but I dont think thats causing your misfire. What are all the specs burned on the chip? What fuel pressure did you tell Jeff when you ordered? Also if your mod list in your profile is up to date, you may want to think about getting a new fuel pump, the stocker doesnt really like a lot of boost.

I tried to update my profile but i'm having some problems with this computer,The chip was burnt for 750cc injectors, boost gauge now is knock gauge, CAS inversion,8000 rev. RPM,900 RPM iddle,And all of the stage 3 chip comes with exept NLTS nor stutter box because my car is an automatic, As far as the fuel pump goes up replaced the stock one with a rewired walbro 190lph, I also have SSAC FMIC, And a logger!!

 

[WHITE GST]

I forgot to add that i'm still running the stock fuel pressure regulator, And i also mounted the new ecu where it shoul be now and no change!!

 

[MountainDew]

I forgot to add that i'm still running the stock fuel pressure regulator, And i also mounted the new ecu where it shoul be now and no change!!

I'd definitely invest in an AFPR. Sounds like that's next on your list for supporting mods.

 

[peypey's ride]

Your goin to need a FPR for those injectors! That might jus be the problem

Edit: are you running an AFC or a MAFT to help tune your fuel?

 

[WHITE GST]

Your goin to need a FPR for those injectors! That might jus be the problem

Edit: are you running an AFC or a MAFT to help tune your fuel?

I tought i didn't need an after market regulalor with 190lph pump.

I don't have neather one of the two tunning tools, because with the chip i tought you did't need to tune that much only fine tune!!

 

[peypey's ride]

You will atleast need a SAFC to tune and you should absolutly have a logger to see whats goin on with your trims and injector duty cycle

 

[WHITE GST]

You will atleast need a SAFC to tune and you should absolutly have a logger to see whats goin on with your trims and injector duty cycle

I already have a logger, but how do i log the injector duty cycle? i don't see it on the selection list in my pda, i'm using pocketlogger!!



THANKS.

 

[black91awdturbo]

his duty cycle is fine with those injectors and 15psi! You will need a safc to fine tune the chip with, you must have a really rich spot on your map causing you to bog. Pull your spark plugs and tell us what they look like and I can help you more.

 

[peypey's ride]

Where are your ltft and stft at? You wanna have them as close to #0 as you can get. The stft will change alot more when driving and you can use a SAFC to tune that.

 

[WHITE GST]

his duty cycle is fine with those injectors and 15psi! You will need a safc to fine tune the chip with, you must have a really rich spot on your map causing you to bog. Pull your spark plugs and tell us what they look like and I can help you more.

I'm checking my plugs and wires today, I'm also goint to use a different set of wires and see if that is the problem, That is what Jeff thinks it is, plugs or wires!!

THANKS.

 

[MountainDew]

I tought i didn't need an after market regulalor with 190lph pump.

I don't have neather one of the two tunning tools, because with the chip i tought you did't need to tune that much only fine tune!!

Generally, you wouldn't need one if that's all you added was the 190. But in your case, you have bigger injectors which an AFPR would greatly help.

 

[Talesin]

And the 190 can overrun a stock 2G FPR when it's been re-wired. Hell, an un-rewired one can do it with some of them.. combination luck of the draw on how well your FPR was manufactured, and the fact that 2Gs run a higher base fuel pressure stock, as compared to 1Gs. A proper AFPR (NOT a B&M CommandFlo POS!!) is vital when you start upgrading the fuel system, to assure that you have a steady and 1:1 rising-rate fuel ratio to tune from. If your fuel drops off unexpectedly, or spikes erratically, it will make tuning a pain.

Make sure your boost gauge line isn't leaking (could be running much higher than 15psi and not know it), and what do you have the boost controller set to? Are you sure you aren't hitting fuel cut? I'd be suspicious about the crappy-near-useless A/F gauge reading full-lean while boosting though, it really should be reading extremely rich.

 

[el guapo]

check the gap on your plugs. what did you gap them at?

 

[WHITE GST]

I borrowed the plug wires from my friend and the back firing is mostly gone i does it just a little bit when the transmission shifts at WOT, But i was able to run 18 spiking to 20psi,
I have not check my plugs yet, but i thing i'm just to replace both! The little back firing i have now could be because a small boost leak?

PS, I'm running Denso Iridium plugs about 3 years old!!

 

[WHITE GST]

I'd be suspicious about the crappy-near-useless A/F gauge reading full-lean while boosting though, it really should be reading extremely rich.[/QUOTE]


I know, It reads the same as it did when a had the stock injectors and ecu, Back when i had the T-25 turbo on it it use to be at the rich part when boosting!

 

[WHITE GST]

I took the spark plugs and wires out of my car yesterday and cleaned the cables real good and also regaped the plugs to .028 they were at .035,They were also some kind of black and smoked and i also cleaned them. Now the car runs much better i can run 18 psi with no problem, the A/F gauge still reads lean but i think the gauge is just trash, The lowest timing i get at WOT is 9* and it goes up to like 16* or so.

THANKS EVERY ONE FOR HELPING ME OUT!!

 

[peypey's ride]

Glad to hear that you got it figured out! Now wasnt that an easy fix, .