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4K power spike...tons of ideas


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Well if anyone has ever driven in a real v-tec honda, that is what my subie is doing. At the low 4k rpm range the power spikes and the car really picks up. Why?

 

Power is at its highest point around 4,400rpm according to edmunds- Show me a power curve please, because mine is not as smooth as I would imagine the engineers made it.

 

Maf?

 

Knock sensor - very possibile but why 4k and not 3k? I do get a stumble in the 2k range which I believe is the knock sensor.

 

Fuel supply/lines/filter(12k old)?

 

Timing belt new ~6k ago - could a jumped tooth cause this?

 

Clutch ~6k ago - maybe adjustment needed on the cable because it is possibily allowing the clutch to slip until I get up to 4k??

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A few things normally cause this:knock sensor, MAF (which I have had a few bad ones that wouldn't throw a code for a long time) and also check your charging system!!!

My dads 95 L 2.2 was just doing this and there was a little corrosion and one of the terminals was cracked. He went and got some of the gold terminals and we slapped them on quick. He called me when he got home and said it was smooth as can be and it was like someone put NOS to the car from how it had been driving.

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I am almost certain that I read in a thread, on here, that one will be ignored in certain situations. I know it seems logical that both work in unison, but I swear I read about it.....Maybe it had to do with closed or open loops...I dunno...

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The O2 sensor is ignored (open loop) until it warms up enough to give a valid reading. The ECU knows it's warm enough based on engine temp and/or time (not sure what the ECU in your car does). After it's warmed up, the system goes to closed loop and O2 sensor is used in conjunction with all of the other sensors.

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