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Discussion Starter · #1 · (Edited)
Ok, so I had my box dyno'd. I'm running more fuel than the engine likes, and then even more fuel when the vvti kicks in. stock engine with only SRI, maniifold back exhaust, high flow cat.

Is there a chip, ecu mod, piggy back, stand-alone comp that will PERMANANTLY allow me to re-map/configure/tune so that I'm not running so rich?

Reaching out on a limb, would a fuel pressure regulator and smaller injectors work, in the sense that I would be able to mechanically limit how much fuel could be injected? Or is my concept of how that combo works all wrong?
 

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Local Boy said:
just intake and exhaust. stock exhaust header.
You have an exhaust yet its stock? I'm assuming your talking about a universal muffler used on all stock piping?

Either way you shouldn't be running rich. I would check to make sure your intake is installed correctly and theres no cracks or anything in the piping. I'd also check the filter and make sure its not dirty or have any holes in the filter that could result in the ecu getting confused and throwing more fuel out than needed.

The best thing i can think of is e-manage. You don't need to upgrade the injectors with only i/e. You shouldn't even need management with that. I would also have someone check the ecu and run test on it to make sure nothing is wrong with it. I don't see how you are running rich with i/e.
 

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Discussion Starter · #6 · (Edited)
sorry, by "stock engine" I meant no force induction, no pulley(s), no nitrous, no fuel mgmt systems, no coil pack boosters, allow me to clarify...

I once ran the AEM cai, dc headers, and a complete custom manifold back exhaust system w/ a high flow cat and an Apexi can.

I've since removed the dc headers and went back to the stock headers. I swapped out the cai for MMW sri. The high flow cat is still in place, but I swapped the Apexi for an OEM style muffler and tip.

I put it on the dyno just for fun. 89hp and when the vvti kicked it, the a/f mixture when from rich, to almost wet.

By the reaction of you two this is not normal, but uhmm, has anyone else dyno'd their cars and looked at their a/f ratio?

and no, no CEL's thrown.

EDIT: as an after thought, can I bring the box into a dealership and have them run a diagonstic on the box to find out what's wrong? Can I do this with the intake and high flow cat in place?
 

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89whp with the header and everything or what? I drive an auto box and i was dyno'd at 96whp with i/h/e for power mods, something sounds way off. 89whp is almost stock output.

It sounds like the combined set up you have, the ecu is misreading and dumping more fuel than is needed, then leaning out on the top end if i read what you are saying correctly.

I'd take it to a well known speed shop to do the diagonstics on the motor, dealership workers half the time usually only know what they learn from training and usually wouldn't know what to do if they were even able to do the testing.

It's hard for me to pin point exactly what could be the cause since i'm not looking at the car personally.
 

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sounds to me like your ECU is just compensating for the mods you threw on. Try pulling your EFI fuses to reset the fuel trim. These computers are to smart for their own good. Anytime you add something on to the car, it will just counteract it. The ECU is sensing an extra lean mixture, and is dumping fuel to the point where it is back to its safe point which is extra rich from the factory.
 

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Ok, let's begin now...
What's the Air/Fuel at? And at which RPM? Gear? Load? Man or Auto? Is the Wide-band o2 black at the tip? Were the wires tampered with? is the CEL on? If so is it p0171 or p0174? How about the Air Flow Sensor? Check fuses and wires going to each of these sensors. Also check the coolant level and ECT sensor. Who's telling you this info? Then why can't they run diag? If you need help let me know, this is what I do.
 

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Discussion Starter · #11 ·
yes right on, this is what I need. I'll look over the info I was given and post up some of these answers this weekend. Thanks SCVScions.
 

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Discussion Starter · #12 ·
ok, so I'm not sure, but I think I was able to upload the three dyno charts I was given into my profile gallery. I'm not sure how to post it here in the thread. SCVScions, do these help any?
 

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That'snormal at that RPM, the computer is trying to keep the pistons cool with that charge above 6000 otherwise the cyl temp would get to high and cause detonation. You can adjust it with Halltech or Capcom, poss. with Apexi but I'm not familar with Apexi. You need to see what the scanner is saying your wide band O2 is doing to track weather or not it's lazy or maybe you have a crack in the pipe before the O2 sucking in air causing the effect.
 
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