Lean at WOT, whyyy?!?
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Lean at WOT, whyyy?!?
I'm having a problem keeping the AFR in check on my 2g.. I'm sorry I don't have any logs to post but I'll explain it the best I can..
The car is a 2g with a '94 7-bolt block, 2g head w/1g CAS, 14b turbo, FP intake, 2.5inch turboback exhaust, Evo9 FMIC w/2.5" pipe, stock 450cc and STOCK BOOST (was running 15 but turned it down because of this..)
In first gear if I floor it at 3k, AFR drops to 12.2 then rises to 12.3 by the end of first. In second gear, same pull, the AFR starts at 12.2 then leans out to 13.2
by redline in second. Third gear pretty much acts the same as second, although it starts to knock around 5k in third. First and second I get 18* or so, third gear flatspots at 14*. If I slowly ease into the gas in second or third to about 60% on TPS, the AFR drops to 11.5:1 and doesn't seem to lean out as much, but it still does (keep in mind I haven't taken it to 7k at half throttle). I'd like to get it to stay at 11.5...
To try fixing it, I've tried a new fuel filter, and rewired the fuel pump with 10 gauge. As far as boost leaks, I had one at the BISS screw that I fixed, and a small one at the throttle body shaft seals, which is still leaking. I've also tried compensating with SAFC, if I add even 3% the car falls on its face in boost.
Does anyone have any insight for me? I could probably just get some bigger injectors, I plan on getting some 650cc anyway, but I'd like to fix the car before I upgrade it anymore if thats possible...thanks!
The car is a 2g with a '94 7-bolt block, 2g head w/1g CAS, 14b turbo, FP intake, 2.5inch turboback exhaust, Evo9 FMIC w/2.5" pipe, stock 450cc and STOCK BOOST (was running 15 but turned it down because of this..)
In first gear if I floor it at 3k, AFR drops to 12.2 then rises to 12.3 by the end of first. In second gear, same pull, the AFR starts at 12.2 then leans out to 13.2
by redline in second. Third gear pretty much acts the same as second, although it starts to knock around 5k in third. First and second I get 18* or so, third gear flatspots at 14*. If I slowly ease into the gas in second or third to about 60% on TPS, the AFR drops to 11.5:1 and doesn't seem to lean out as much, but it still does (keep in mind I haven't taken it to 7k at half throttle). I'd like to get it to stay at 11.5...To try fixing it, I've tried a new fuel filter, and rewired the fuel pump with 10 gauge. As far as boost leaks, I had one at the BISS screw that I fixed, and a small one at the throttle body shaft seals, which is still leaking. I've also tried compensating with SAFC, if I add even 3% the car falls on its face in boost.
Does anyone have any insight for me? I could probably just get some bigger injectors, I plan on getting some 650cc anyway, but I'd like to fix the car before I upgrade it anymore if thats possible...thanks!
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1990 GS-T
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Negative, FPR has a vacuum line going directly to the intake manifold. I tore all that crap on the firewall off. No more solenoids and the only vaccuum lines are the BOV, FPR, and wastegate lines. No EGR or FIAV.
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Last edited by omgosh; Oct 12, 2008 at 05:53 PM.
OG MUDBONE 240sx
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fuel pump might be going bye bye. sounds like it. go get a fuel pressure tester or fuel pressure gauge of some sort. tap into your pressure line on your fuel rail and run the gauge up to your window, get into boost and watch the gauge. see if fuel pressure rises at first and then dies off.
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