Factory Tach is off
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Factory Tach is off So some how the tach on my cluster is off, the PCM is showing correct according to my tuner. what could cause this?
Crank sensor failing?
Power wire running to close to tach? *I added gauges WB and OP as well as a hard wire for my V1*
I know the signal wire is measured by Hertz so could it be interference? The tach used to show proper on my old motor. after building a new one its been off since the first start up.
yes i know the factory tachs arnt 100% accurate.. but it shouldnt show that high for an idle
Crank sensor failing?
Power wire running to close to tach? *I added gauges WB and OP as well as a hard wire for my V1*
I know the signal wire is measured by Hertz so could it be interference? The tach used to show proper on my old motor. after building a new one its been off since the first start up.
yes i know the factory tachs arnt 100% accurate.. but it shouldnt show that high for an idle
To determine whether the dash cluster is at fault you would need to have a scanner that can actually read the cluster's input reading. If the cluster is given the signal it is showing then the pcm is giving bad information. The cluster is not hard wired to the sensor it uses data from pcm. I personally have access to a tech 2. Probably a snap on scanner wou
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To determine whether the dash cluster is at fault you would need to have a scanner that can actually read the cluster's input reading. If the cluster is given the signal it is showing then the pcm is giving bad information. The cluster is not hard wired to the sensor it uses data from pcm. I personally have access to a tech 2. Probably a snap on scanner wou
Oops. .. capable of reading the cluster. Your regular auto zone scanners won't do it. I probably shouldn't be saying to much of the exact way you can do this being I can't verify on my car being it is in a million parts but I am going by past experience of being a mechanic for too many years. Lol. Maybe some one else might chime in. As far as fixing. That would probably be a programming error. From there I would probably just go back to stock and see what happens.
That's about on par with what I have, at 800 rpm it shows me at 1,100 on the tach. I have HPT as well as an Aeroforce Interceptor that both indicate rpm at 800 while tach is at 1,100.
Also I've no tach driven manual cars long enough that audibly I can confirm the engine is idling under 1000 so I know it's not the pcm reading wrong.
Our Gauges just read high. At some point if it gets worse I'll look into it. I just thank myself its not like the dashs on the third gen Camaro's. My buddies 88 Camaro tach reads 4k at idle :p
Also I've no tach driven manual cars long enough that audibly I can confirm the engine is idling under 1000 so I know it's not the pcm reading wrong.
Our Gauges just read high. At some point if it gets worse I'll look into it. I just thank myself its not like the dashs on the third gen Camaro's. My buddies 88 Camaro tach reads 4k at idle :p
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That's about on par with what I have, at 800 rpm it shows me at 1,100 on the tach. I have HPT as well as an Aeroforce Interceptor that both indicate rpm at 800 while tach is at 1,100.
Also I've no tach driven manual cars long enough that audibly I can confirm the engine is idling under 1000 so I know it's not the pcm reading wrong.
Our Gauges just read high. At some point if it gets worse I'll look into it. I just thank myself its not like the dashs on the third gen Camaro's. My buddies 88 Camaro tach reads 4k at idle :p
Also I've no tach driven manual cars long enough that audibly I can confirm the engine is idling under 1000 so I know it's not the pcm reading wrong.
Our Gauges just read high. At some point if it gets worse I'll look into it. I just thank myself its not like the dashs on the third gen Camaro's. My buddies 88 Camaro tach reads 4k at idle :p
Maybe your buddy should try adjusting the tach output on HP Tuners if he is that far off. LOL
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From: Moore, Oklahoma