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Only runs with cam sensor unplugged. Have replaces cam and crank position sensor also o2 sensor changed plugs and wires and pulled front end apart and checked timing. Still only runs with cam sensor unplugged .. any thoughts?

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more information might be helpful -


read the check engine light codes - list all the codes here - obviously the cam code is going to be on...what else?

 

was this car running perfectly one day - then just stopped running?

or is it a craigslist special you bought for $300 yesterday?

 

any prior major work, issues, or accidents?

 

running without the cam sensor sounds crazy...i wanna go home and unplug the cam sensor on my 95 legacy and see if it starts!

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Still only runs with cam sensor unplugged

this is ia ECU ''fail safe'' situation.

when there is no cam signal, or whatever,

the ECU uses the crank signal to operate both the fuel and the spark.

i found this to be very very smart.

and i only know this because i read it here or on another forum.

 

i would check the wiring.

if it does not run with the sensor,

but runs with out the NEW sensor,

then there is a problem with the wiring.

or maybe the ECU.

but would check the wiring first.

 

did tis happen suddenly?

develop over time?

did it start to run poorly and then quit,

or just would not run one day?

 

ECUs do not fail often.

so check the wiring,

look for a break,

or a worn spot,

or mouse damage.

or bad pins in the connectors,

at the sensor and at the rear of the engine.

 

i do not know which makes more sense,

a complete break,

or a wire grounded out.

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this is ia ECU ''fail safe'' situation.

when there is no cam signal, or whatever,

the ECU uses the crank signal to operate both the fuel and the spark.

i found this to be very very smart.

and i only know this because i read it here or on another forum.

 

This. Is. Amazing. to me....wow. Thanks for the info.

Edited by wtdash
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Never heard of that before.

 

Broken wiring should set a code and wouldn't matter of the sensor was plugged in or not, because the ciruit is open anyway, unless the signal is dropping intermittently.

Same with short to ground or one wire shorted to the other.

 

Either the sensor is giving the wrong signal, (possibly the wrong cam sprocket installed) or there is a problem with another sensor that is being corrected or overrided by the ECU going into failsafe mode.

 

It seems to me that unplugging some of the other sensors, such as the temp sensor, or MAF/MAP should produce the same result.

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