engine misfire possible solution.

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azazel19
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engine misfire possible solution.

Post by azazel19 »

I've been having a problem with a misfire on cylinder 1 or 3 can't remember at high speeds. apparently others are too i searched and searched and everyone does the same thing and others get head work new cams and same issue. changing coil plugs wires doesn't seem to work and i ran across one site on my journey about crank shaft position sensor and that's the first out of many threads i've read.

what are the chances this could be a faulty crank sensor? it's not real cheap and from what i've read it needs to be gapped. so if this could be a fix how what is the gap i would imagine it's in the fsm. hope this if a fix because i'm at a loss only thing i haven't changed is the o2 sensor and i would imagine it would be an 02 fault in the computer but just registering as a misfire.
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JohnnyC
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Post by JohnnyC »

Actually I've considered the crank shaft sensor as being the culprit. I had been working in that area when the problem originated. I might first try and clean it to see what that does, perhaps there is enough residue on it to mess up the signal.

The crank shaft sensor has a small metal tip that points towards some cogs on the crankshaft pulley. It aparently reads each time one passes the metal tip and then reports to the ECU. It would make sense that a dirty crankshaft sensor would have trouble, except for one thing, why only at high speed and not high RPM, unless it's only under a certain load or something?

I'll have to look into that further. Good thinking.
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daewoomofo
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Post by daewoomofo »

i noticed that the CPS is atually magnetic, you night have some thing out of line down there, but it never hurts to clean everything
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MMamdouh
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Post by MMamdouh »

maybe the dirt decreased the sensor's ability to detect the cogs and at high speed the detection process is so hard that the ECU start to think thier is a misfire.

this sounds to be logical as the crank position sensor is part of the misfire detection mechanism indeed, i,d check the sensor and the metal cogs for dirt and foregin objects and then have a test drive.

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lanowoo
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Post by lanowoo »

mt cps is missing its little clips that hold it to the connector. some guy in the garage broke it i think and thats when my cel and 1 cyly misfire. thats why i try to tell everybody to visually check / pull slightly on the injectors or anywire at that.
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