cam position sensor?
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rabidscoobie
10 Year Member
A bad diode in the altenator can also throw that code.had it happen before.Actually if the diode gets bad enough it will throw all types of codes.
The CPS rarely goes bad.
For some reason, a faulty diode in the alternator causes this code to trip as well. Most often, it's usually the alt.
For some reason, a faulty diode in the alternator causes this code to trip as well. Most often, it's usually the alt.
It causes a problem because the diode is a "one-way electron valve" that cuts off the negative swings of the voltage (the alternator produces AC voltage itself). When the diode goes, the DC power becomes noisy and that plays hell with the computer's ability to function properly... It becomes erratic and can decide that sensor values are bad when the problem is a bad Vcc.
whitemustang89
Member
ditto. i was having this problem. changed the cps went thru my voltage system numerous times. just drop the 200 like i did and your problem will go away. but try the CPS first b/c its only like 12-15 bucks
I am a computer scientist by day, and the most common issue we see causing computers to suddenly go ape is a bad power supply. An oscilloscope will quickly reveal that the +5 or +12 voltage outputs are noisy rather than flat DC voltages. But the interesting thing is that you typically don't get a machine that refuses to boot. It just becomes "flakey", sometimes infrequently, sometimes completely bananas all the time.
The alternator A/C to D/C conversion has to go right. Lights and stuff don't care. The computer does. And you can't tell with a normal voltmeter. A good one that can pretend to be an oscilloscope will show the DC output to be not so "DC" once you know what to look for.
Other things that will cause this include corrosion in the connector blocks where the wiring harness is disconnected to make it easy to remove the motor. Check it and make sure there is nothing but clear dielectric grease in there, no green gunk. Had that on an older 90 fox we used to run on the street/strip.
The alternator A/C to D/C conversion has to go right. Lights and stuff don't care. The computer does. And you can't tell with a normal voltmeter. A good one that can pretend to be an oscilloscope will show the DC output to be not so "DC" once you know what to look for.
Other things that will cause this include corrosion in the connector blocks where the wiring harness is disconnected to make it easy to remove the motor. Check it and make sure there is nothing but clear dielectric grease in there, no green gunk. Had that on an older 90 fox we used to run on the street/strip.
rabidscoobie
10 Year Member
Yes it will.With the bad diode in the alt your not getting stable or correct power.Your alt is charging and dis-charging at the same time,not only that but the longer you wait the more your battery dies...wait too long your gonna also need a new batt.That bad alt is causing sensors to go haywire,giving incorrect readings the computer,which can cause misfires,backfires,CEL's and im betting that your lights at night arent as bright or are brighter than normal...at least those are all the probs I had on my GT with the bad diode.
Also I 1st went to autozone to get the alt checked and they said it was all good..wrong.So I went to a Advance Auto Parts and after about 2 mins he said the diode was bad in the alt...$250 later and it ran just like new again.But it was that much cause I bought lifetime warranty...could a got 1 for $200.
