Cadillac Owners Forum banner

1 - 13 of 13 Posts

·
Registered
1999 Seville SLS, 2007 STS-4 V.6
Joined
·
72 Posts
Discussion Starter #1
Hey guys,

So yesterday I was driving my car and I was on my way back home it's like a 35-40 minute drive. I stopped at a red light suddenly the car started to "shutter". I guess you can say, or shake but it will only do it like every 3-5 seconds. No engine light came on nothing, but since it was night I noticed that the head lights would some what dim in and out. Exactly at the same time it would shake, same thing with the inside lights. I drove the rest of the way home but once the car is running it feels perfectly fine no problems nothing at least not that I can tell. Like I said every time it's at a stop light or it's parked it does that little shake every 3-5 seconds. My cousin whom is some what a mechanic lol said it could be an ignition coil, he checked the spark plugs and said they were fine, anyway I was able to pull the codes and this is what I got.

P0340 - Camshaft Position (CMP) Sensor Circuit

P0717 - Input Speed Sensor Circuit Low Input

Now I know nothing about being a mechanic, but it would be great to have a second opinion, that way I can get my cousin to fix it lol. I would appreciate any help, thank you guys! :)
 

·
Premium Member
1997 ETC
Joined
·
4,976 Posts
CMP is a relatively easy replacement job, it sits on the passenger side, on the rear head, held by a 10mm bolt and has a two prong electrical connection to it. with my skinny hands and the bolt loosened i did it in 15 minutes
 

Attachments

·
Registered
1999 Seville SLS, 2007 STS-4 V.6
Joined
·
72 Posts
Discussion Starter #3
Thank you for the reply and diagram, I appreciate it. Do you think that is the reason the car is acting the way it is? I hope it's an easy fix lol, reading all the threads in this forum has scared the crap out of me with any little thing lol.
 

·
Premium Member
1997 ETC
Joined
·
4,976 Posts
when mine went out my car was shaking a bit. Use an open end 10mm wrench for the bolt and be patient. And get an AC Delco one, O'Reilly's one made by CVB (or something like that) wont fit the electrical connection it'll have three prong, and never go to Autozone

GM's description for this sensor:

The camshaft position sensor extends into the rear cylinder head. As the rear cylinder bank exhaust camshaft turns, a steel pin on its drive sprocket passes over the magnetic camshaft position sensor. This creates an "ON-OFF-ON-OFF" signal sent to the ignition control module similar to the crankshaft position sensors. The camshaft position sensor produces one "ON-OFF" pulse for every one revolution of the camshaft or every two revolutions of the crankshaft. This allows the ignition control module to recognize camshaft position.


 

Attachments

·
Registered
1999 Seville SLS, 2007 STS-4 V.6
Joined
·
72 Posts
Discussion Starter #6
Just out of curosity,

Does your car startup easily when you turn the key?
well I noiced that when I drive it for a verrrrry long time, and I shut it off and turn it back on it does slightly feel like it has trouble but it fires right up on the first turn of the key.
 

·
Registered
98 eldo/KD54 w/N37,T96,QA1,D55,DS3,U1Z. U3R next
Joined
·
2,125 Posts
Change both CRANKSHAFT position sensors.

I had the 340 code, along with 385 and 386. I had read on the devilles that the crankshaft position sensors were "finicky" to say the least.

Changed the crankshaft position sensors, starts with barely turning the switch now.

Go back to post #4, attached images #7. CAMSHAFT position sensor is used by the pcm for the sequential FUEL injection system.

In attached images in post #4, 1-6 state the CRANKSHAFT position sensors control when the ignition "fires".

Not to save the CMP can't fail, but my experience has been the CKP sensor has usually been the culprit.
 

·
Registered
1999 Seville SLS, 2007 STS-4 V.6
Joined
·
72 Posts
Discussion Starter #9
Hey guys, I forgot to thank you for all the help.

Now I changed the Cam sensor and it stopped giving me that code, but a while back the car started doing the same thing. So I checked the codes and nothing comes up that could be related to the situation. So my cousin took a look at it again. He checked out the ignition coils. Even disconnected the wires that go to them needless to say he got shocked a couple times lol. Anyways he noticed that one of them didn't have a spark. I'm guessing that this might be the problem. What do you guys think? Would an ignition coil cause the car to feel this way? or could it be something else? I haven't gotten a misfire code which I use to when the cam sensor was bad but the car still feels horrible when I'm at a red light or when I'm in park or something like that. otherwise when it's going it feels pretty good. Any help would be appreciated.
 

·
Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
Joined
·
70,670 Posts
If your spark plug wires are original, they're way past due for replacement. AC Delco plugs - #41-950 - and an AC Delco wireset. One or more coil(s) could be weak or have a cracked case. Plentiful at junkyards or talk to Chris at Rippy Cadillac Parts over there >>>>>
 

·
Registered
Joined
·
35 Posts
Submariner409 said:
If your spark plug wires are original, they're way past due for replacement. AC Delco plugs - #41-950 - and an AC Delco wireset. One or more coil(s) could be weak or have a cracked case. Plentiful at junkyards or talk to Chris at Rippy Cadillac Parts over there >>>>>
I would bet bad coil. I just replaced coil on my 93 Camry wagon. Misfire at idle. No code. New coil fixed it.

----------

My bet us the coil. I just replaced the coil on my 93 camry wagon. Had a slight misfire at idle but no codes. Tried plugs and wires first. Coil fixed it.
 

·
Registered
1999 Seville SLS, 2007 STS-4 V.6
Joined
·
72 Posts
Discussion Starter #12
If your spark plug wires are original, they're way past due for replacement. AC Delco plugs - #41-950 - and an AC Delco wireset. One or more coil(s) could be weak or have a cracked case. Plentiful at junkyards or talk to Chris at Rippy Cadillac Parts over there >>>>>
Thank you for the reply :).

He checked the spark plugs and said that they seem fine. Now the wires I'm not sure if they are the original or not. I'm guessing that they might be. So it might either be a wire or the coil itself huh. Well I guess I'm going to try the wires first and if that's not it then the coils and spark plugs. From the symptoms that I described do you think that one of those might be the issue?

----------

I would bet bad coil. I just replaced coil on my 93 Camry wagon. Misfire at idle. No code. New coil fixed it.

----------

My bet us the coil. I just replaced the coil on my 93 camry wagon. Had a slight misfire at idle but no codes. Tried plugs and wires first. Coil fixed it.
I was thinking the same. I just wanted to make sure. The way the car feels is annoying and somewhat embarrassing when I have a passenger lol
 

·
Registered
98 DeVille, 97 DeVille d'Elegance
Joined
·
7,345 Posts
Checked the plugs? Difficult since unless very bad they'll look good. Unless you know they have only a few thousand miles on them I would change them.
 
1 - 13 of 13 Posts
Top