New plugs, wires, cap and rotor now service engine soon light

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SunlitComet

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yeah if you have a light you have a code. try a different mech. if verified you have no active or stored codes then it is possible the pcm has a fault. very unlikely tho.
 
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Sgt Tahoe

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OK, I have the code P1345, camshaft position sensor. I won't have time before work to test the sensor so I will check it tomorrow. My question now is how can changing out the plugs, wires, cap, and rotor help cause this problem? Is it possible I don't have something correct with the cap and rotor that is causing this problem? Or, is this just completely unrelated and just a matter of coincidence?
 

kaoticlife

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I'm changing all today. Cap, rotor, plugs and wires. And I have to reset this truck correctly? Kinda stupid

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kaoticlife

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I get ya...sorry just drinking from the Tahoe hate-er-ade today..loosing my love for the truck lately. I'm guessing you mean when you change the whole distributor..

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SunlitComet

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when you change cap and rotor you have to re-set them properly:
http://www.sunlitcomet.com/pdf/automotive/tahoe/98-99/1999-Tahoe-p1345.pdf

if you search in the web you'll also find a manual procedure without the scan


actually you don't re-set them. if you triggered that code after changing those parts you bumped the dizzy off a bit in degrees because the clamp was not tight enough. otherwise you never adjust any vortec dizzy just because you change the cap or rotor. try adjusting it a few degrees in either direction. if it misfires go the opposite way you will likely put it back in the proper alignment and the light will eventually go out. cheapest way to do it. no need for a scanner unless you really can't get it down. and if you got one the scanner needs to be able to read the CAM_RETARD pid.

---------- Post added at 01:55 PM ---------- Previous post was at 01:53 PM ----------

I meant you have to install it following a procedure

http://www.gmtruckcentral.com/articles/distributor.html


again, not needed just because you do cap and rotor.
 
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Sgt Tahoe

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Problem solved

After researching the possible causes and running down all the suggestions, it turned out my cam shaft position sensor was bad. Although it was reading correctly on my volt meter, apparently there was something damaged during the process. I finally just replaced the sensor at the suggestion of an older mechanic and the problem is solved. If anyone else has the problem, I would suggest starting with testing the plug to make sure you did not pull something loose while pushing and pulling on the cap. Next, check the voltage in and out of the plug. You should have 12 volts coming in with the ignition turned to on and 5 volts coming out when the engine is running. Even if you have the correct voltage don't be afraid to replace the sensor. I had the correct voltage but apparently it is possible for the sensor to work at times and not at others. Make sure to use quality parts and don't cut corners. Thanks for all the help and suggestions. If you ever have this problem don't hesitate to email me, I have spoken with more people and read more about the P1345 code than I care to admit. Also, as a side note, make sure the vents are clear on your distributor. There was a service manual update several years ago and apparently many trucks have not been done yet. It is an easy fix and worth doing while you are in there.
 
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SunlitComet

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sorry but that test is somewhat invalid. while you can test the connector to make sure 12 volt can get to the sensor you can not be sure the sensor will actually use at times. and the output you said of five volts is false info. the sensor outputs logical data in electrical form. what you are seeing is the accumulation and smoothing averages of a voltage signal ticking on at the same rate as your rpm as displayed on a multi meter that can not show the differences quickly enough. only an oscilloscope or the pcm can interpret it and that is why only a true scan tool can really tell you if it is working properly or not. as for the vents while you can clean them often the parts in your dizzy are worn enough that the build up of gases can still cause issues. rebuild it entirely and clean out the screens or replace it if it is of age as new ones are a better at dealing with it if you find powdery substances in the cap or you are constantly burning them out. at any rate not detrimental to the trucks running if not working normally. main purpose is to help determine what cylinder is misfiring when it does occur. vehicle will start without it.
 
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