New Engine Acceleration Problems
All Around Maxed
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New Engine Acceleration Problems
Hey guys, made it to Boston OK. 15ft truck w/ the car carrier in back made for some scary driving through the rain at 70-75mph...
Anyways, I met up w/ Scott on Sat to upgrade my ECU ROM Tune from the beta version I was running.
We ran into the same probs since mile 0 of the engine: under load, the engine will not accelerate past 3.5-4.0 RPM. Acts like a fuel cut off, it just falls flat. I can redline it in nuetral though.
On the dyno, there were no signs of vacuum leaks or bad fuel pressure. A/F looked solid at WOT.
Previous engine ran fine aside a cooling problem. Nothing has changed in terms of ignition/fuel/turbo goodies.
Can I safely assume this is ignition related? Think a Nissan consult can pinpoint this?
Jesse
PS - RPS 475tq clutch is super driveable, I love it!
Anyways, I met up w/ Scott on Sat to upgrade my ECU ROM Tune from the beta version I was running.
We ran into the same probs since mile 0 of the engine: under load, the engine will not accelerate past 3.5-4.0 RPM. Acts like a fuel cut off, it just falls flat. I can redline it in nuetral though.
On the dyno, there were no signs of vacuum leaks or bad fuel pressure. A/F looked solid at WOT.
Previous engine ran fine aside a cooling problem. Nothing has changed in terms of ignition/fuel/turbo goodies.
Can I safely assume this is ignition related? Think a Nissan consult can pinpoint this?
Jesse
PS - RPS 475tq clutch is super driveable, I love it!
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Ings RSpec, Built KA24DET, GT3071R
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Ings RSpec, Built KA24DET, GT3071R
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shit that sucks man. Glad to see you made it safely to your destination. I would think it would have to be ignition related but what I have no idea.
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All Around Maxed
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There are more things that suck: stripped valve cover bolts, I'm almost out of helicoils (possible to buy them somewhere?), having to polish the valve cover, leaking coolant from the intake manifold. Luckily, I removed all the studs on the mani, so removal of upper/lower takes about 30min.
Jesse
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it could be a few things but the only thing I have had happen to me like that it turned out to be a bad or dirty air temp sensor it would just sort of stop the car from bosting in gear when I would get on it. Can you step on the gas slowly without actuating the turbo open and make it to redline without it happening? It sounds like you can rev up in neutral right? give us some more details it could something really easy like that sensor.
All Around Maxed
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DJ, I believ the KAs don't rely on AITS for engine performance, they're merely OBD sensors.
The cut-off occurs under partial throttle as well
Needless to say, it's been a challenge to properly break-in the engine...
The cut-off occurs under partial throttle as well
Needless to say, it's been a challenge to properly break-in the engine...
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Did you try checking timing at the crank during the run? I could see a cap/rotor or CAS problem happening under load. Maybe spark plug gap? Also, what John said. Are you using a wet element (K&N) filter? The oil is known to cause problems with MAFS. That's why Apexi pwns.
