under WOT at about 4k it gose from rich to stoich "sp?" then back to rich, there is a power lose related to this. you can feel the power go away and come back. also when i let it return to idle from redline I don't get one big pop and flame, i get 3 or 4 small pops with almost no flame. I was thinking it may have been the TPS. but it has a good WOT and idle reading. should i try the MAP ground thing? what all could it be?

 

Laggy auxilliary ports maybe? When my car is not fully warm I lose power under WOT at about 4K RPM. When I get to about 4.5K it surges and the power returns. Just a thought...

 

no aux. sleaves.

 

sounds like the problem i had, i reset the TPS and regrounded everything and it went back to running fine. but i'm pretty sure my TPS is on the way out so the regrounding my have fixed it, i say try to ground everything , starting with the coils (this helped me alot). what mods do you have to help us diagnos what else it could be?

 

Maybe lagging seconday injectors, try regrounding the ECU

 

Yeah, I say it's the injectors. The secondaries are supposed to kick in around 3800rpm. If they're sticking or lagging at all, they could cause all of your symptoms.

If you end up replacing them, I would recommend shipping them out to RCEngineering to get remapped.

Good luck

 

i agree with everyone on the injectors. They would definatly be first on my list of suspects.

 

Iv got a FC1000 box so i dont think it would be the coil ground and I get a good spark so i dont think iv burnt out the coil yet.
the list of mods are.
the FC1000 & 10mm wires
S5 intake with wired open vdi and no aux sleaves.
port matched runners
UD pully, no ps, ac, ap, ect.
no bac, iac, ect,
2.5" cat replacement pipe, RP cat back " with BIG leak due to no gasket at man/cat"
the car ran better than stock, then.... it dident.
I will re-ground then see what happens.

 

fuel cut. sounds early but it may happen if you are WOT from the bottom up.

secondary injectors clogged maybe?

 

ok. all i got to today was the ground that's on top the block. It did not fix "the problem" but where it did run good, it now runs better. I have yet to look at the tps to see it is misadjusted.... for the 6th time in one week. next up is the MAP,O2, and ECU. Im also going to try a tps that is known to work and see if that helps.

 

Stoichiometric balance is the perfect air to fuel ratio.......Does it go to the LEAN part of the guage?

 

it drops off. all the way off then pops back. my frind thinks im going to rich when the secondarys come on making the car bog down and as unburnt fuel it reads lean. but if there is unburnt fuel would it not go full rich on the gauge?

 

well i replaced the spring that was missing from the tps adj. and grounded the o2 and map... still nothing.

 

ok. the ECU, MAP, O2, and engine top wires have been grounded. the injectors are clean. im runing good gas with a new fuel filter. now have the f2000, R100 magnacore's, and denso iridium plugs. the idle is unbelivable, the power it awsome, the back fires have returned to normal. BUT IT STILL LEANS OUT!! the only thing i know of would be the TPS, or the ECU.