[brm7675]

I have a 2011 CTS 4 3.0 engine. It has just over 85,000 miles on it. Back in November I had two occasions where it appeared like the car was going to stall out. The first was first thing on a cold morning when I started the car and began to back up. The second was a week or so later when I was coming up on a stop light and was slowing down it sputtered again. Neither time did it actually stall. But in both cases the engine light did come on and blink a few times then went off. I took the car to a Autozone but they showed no code. I then took it to my normal mechanic shop and they said they did find a P0300 code. They recommended and I approved replacement of all spark plugs and coils. This was on black Friday in November.

The car has since been running fine with no issue. Then on Monday morning as I was approaching a stop light again it acted like it was going to stall as I slowed down, the engine light blinked a few times but went off and the car drove fine the rest of the day on Monday and Tuesday. Then this morning I started it up and after sitting for a few seconds (in park in my driveway) it again acted like it was going to stall and the engine light blinked again. But I gave it a little gas and it was fine and no engine light and as I drove to work the engine was fine.

So I am pretty sure it's not the plugs or coils, doing some research on the web led me to maybe it's a fuel pump issue or fuel pump relay issue. Has anyone had this type of issue with there Cadillac's? How do you check either of those issues to see if that might be the problem?

 

[tinman]

GM has a document addressing - at least in part - the P0300 code. PM me your email and I will send you a copy for what it's worth.

 

[tinman]

You probably can't PM since you are a rookie. Post your email right here, I will copy it down and then immediately remove it so the web crawlers don't find it.

 

[brm7675]

You probably can't PM since you are a rookie. Post your email right here, I will copy it down and then immediately remove it so the web crawlers don't find it.

[email protected]

 

[Joseph Upson]

I have a 2011 CTS 4 3.0 engine. It has just over 85,000 miles on it. Back in November I had two occasions where it appeared like the car was going to stall out. The first was first thing on a cold morning when I started the car and began to back up. The second was a week or so later when I was coming up on a stop light and was slowing down it sputtered again. Neither time did it actually stall. But in both cases the engine light did come on and blink a few times then went off. I took the car to a Autozone but they showed no code. I then took it to my normal mechanic shop and they said they did find a P0300 code. They recommended and I approved replacement of all spark plugs and coils. This was on black Friday in November.

The car has since been running fine with no issue. Then on Monday morning as I was approaching a stop light again it acted like it was going to stall as I slowed down, the engine light blinked a few times but went off and the car drove fine the rest of the day on Monday and Tuesday. Then this morning I started it up and after sitting for a few seconds (in park in my driveway) it again acted like it was going to stall and the engine light blinked again. But I gave it a little gas and it was fine and no engine light and as I drove to work the engine was fine.

So I am pretty sure it's not the plugs or coils, doing some research on the web led me to maybe it's a fuel pump issue or fuel pump relay issue. Has anyone had this type of issue with there Cadillac's? How do you check either of those issues to see if that might be the problem?

My suspicion would be with the crank position sensor and in tank fuel pump, both of which can cause intermittent and unpredictable stalls for weeks of driving. Increasing throttle input can potentially improve the function of either in a weak state because of the slight bump in current delivered by the alternator when the engine rpm is raised.

 

[sefiro]

- if it occurs when the car is cold, bad water temp sensor could reporting a warm engine causing a rpm drop
- check fuel pressure
- if you are not getting anymore codes, then air/fuel ratio is off. Throttle body may need cleaning, fuel injector failing, air intake clogged etc. Will probably need a scanner to read sensors to see what is reporting out of wack.

 

[tinman]

Good ideas you two.

OP, remove your email. I sent you a regular email.

 

[bear4625]

I have a 2011 CTS 4 3.0 engine. It has just over 85,000 miles on it. Back in November I had two occasions where it appeared like the car was going to stall out. The first was first thing on a cold morning when I started the car and began to back up. The second was a week or so later when I was coming up on a stop light and was slowing down it sputtered again. Neither time did it actually stall. But in both cases the engine light did come on and blink a few times then went off. I took the car to a Autozone but they showed no code. I then took it to my normal mechanic shop and they said they did find a P0300 code. They recommended and I approved replacement of all spark plugs and coils. This was on black Friday in November.

The car has since been running fine with no issue. Then on Monday morning as I was approaching a stop light again it acted like it was going to stall as I slowed down, the engine light blinked a few times but went off and the car drove fine the rest of the day on Monday and Tuesday. Then this morning I started it up and after sitting for a few seconds (in park in my driveway) it again acted like it was going to stall and the engine light blinked again. But I gave it a little gas and it was fine and no engine light and as I drove to work the engine was fine.

So I am pretty sure it's not the plugs or coils, doing some research on the web led me to maybe it's a fuel pump issue or fuel pump relay issue. Has anyone had this type of issue with there Cadillac's? How do you check either of those issues to see if that might be the problem?

My suspicion would be with the crank position sensor and in tank fuel pump, both of which can cause intermittent and unpredictable stalls for weeks of driving. Increasing throttle input can potentially improve the function of either in a weak state because of the slight bump in current delivered by the alternator when the engine rpm is raised.

My question would then be why after having the plugs and points replaced and the throttle cleaned would I drive for about 5 weeks and about 1500 with no issue?

 

[bear4625]

- if it occurs when the car is cold, bad water temp sensor could reporting a warm engine causing a rpm drop
- check fuel pressure
- if you are not getting anymore codes, then air/fuel ratio is off. Throttle body may need cleaning, fuel injector failing, air intake clogged etc. Will probably need a scanner to read sensors to see what is reporting out of wack.

When I had the plugs and points replaced they also did a cleaning of the throttle body. As someone who is extremely navie about cars is why is it so random and why was I able to go about 6 weeks and drive over 1500+ miles after the work with no issue.

 

[bear4625]

You probably can't PM since you are a rookie. Post your email right here, I will copy it down and then immediately remove it so the web crawlers don't find it.

Thanks

 

[Long]

You probably can't PM since you are a rookie. Post your email right here, I will copy it down and then immediately remove it so the web crawlers don't find it.

Get rid of that email address, OP--they're close...:spider::spider::spider::spider:

Go to your post, select edit.
Wipe out your email address.
It will require a minimum of 4 characters to submit, so replace it with "edit", "....", etc.

 

[Joseph Upson]

My question would then be why after having the plugs and points replaced and the throttle cleaned would I drive for about 5 weeks and about 1500 with no issue?

That's an easy question. With the exception being aftermarket ignition systems like MSD (Multiple Spark Discharge) for example, advertised high energy ignition coils usually do not improve ignition performance alone. The laws of physics stipulate that only as much energy as is required will be delivered in order for a spark to jump the spark plug gap, in other words, you will not get 50,000 volts from a coil capable of it, to jump an air gap that only requires 15,000 volts.

With that stated, as the spark plug electrode wears, the gap widens and the energy required to jump that gap increases although within the capabilities of the ignition coil. When an ignition coil is required to deliver more energy closer to its limit, it also runs hotter which contributes to its demise over time.

The crank position sensor delivers an electrical signal also and I believe the sensor on the CTS is an inductive sensor instead of the Hall effect sensor, because it has three terminals now instead of two. In one sensor, the speed of the engine affects the frequency generated, in the other it affects the frequency and voltage delivered.

You replaced two very important components in the ignition system and noticed a temporary improvement in performance which is a good sign you're headed in the right direction, although I would have just stuck with the plugs in the absence of a miss at a specific cylinder. Ignition coils have integrated circuits in them now so they're no longer uncomplicated components. The new coils may have been able to respond to the signals from the cranks sensor theoretically speaking. If the crank sensor is wearing out and the signal weakening further, symptoms naturally would return.

I'm reasoning based on my understanding of the ignition system which is limited, and the knowledge I gained from one of my favorite subjects, physics. It's highly unlikely all 6 coils went bad at once, and having heard such a recommendation before (due to uncertainty), I wouldn't consider a technician that suggested I replace all of my ignition coils, before replacing the crank sensor on an 85k motor (which is cake work for ignition coils) my friend. That's not the kind of Black Friday I'm interested in.

You can lose 3 ignition coils and keep driving. Lose your only crank sensor and you stop dead in your tracks. I had a similar incident to yours in our Nissan early last year, which has over 100k miles on it. Stopped at a light, the car sputtered and stalled, (right next to a mobile auto mechanic) it had never done that before. I replaced the crank sensor within the following 2 weeks and it has not done it since. The coils had already been replaced the previous year as they started going out one by one. I also replaced the crank sensor in the CTS not long after the Nissan as preventive maintenance.

I don't know what caused the trouble you have encountered, it may not be the crank sensor, but it is a crank sensor symptom and a common one at that.

 

[brm7675]

You probably can't PM since you are a rookie. Post your email right here, I will copy it down and then immediately remove it so the web crawlers don't find it.

Get rid of that email address, OP--they're close...:spider::spider::spider::spider:

Go to your post, select edit.
Wipe out your email address.
It will require a minimum of 4 characters to submit, so replace it with "edit", "....", etc.

It doesn't offer me an "edit" option

 

[brm7675]

That's an easy question. With the exception being aftermarket ignition systems like MSD (Multiple Spark Discharge) for example, advertised high energy ignition coils usually do not improve ignition performance alone. The laws of physics stipulate that only as much energy as is required will be delivered in order for a spark to jump the spark plug gap, in other words, you will not get 50,000 volts from a coil capable of it, to jump an air gap that only requires 15,000 volts.

With that stated, as the spark plug electrode wears, the gap widens and the energy required to jump that gap increases although within the capabilities of the ignition coil. When an ignition coil is required to deliver more energy closer to its limit, it also runs hotter which contributes to its demise over time.

The crank position sensor delivers an electrical signal also and I believe the sensor on the CTS is an inductive sensor instead of the Hall effect sensor, because it has three terminals now instead of two. In one sensor, the speed of the engine affects the frequency generated, in the other it affects the frequency and voltage delivered.

You replaced two very important components in the ignition system and noticed a temporary improvement in performance which is a good sign you're headed in the right direction, although I would have just stuck with the plugs in the absence of a miss at a specific cylinder. Ignition coils have integrated circuits in them now so they're no longer uncomplicated components. The new coils may have been able to respond to the signals from the cranks sensor theoretically speaking. If the crank sensor is wearing out and the signal weakening further, symptoms naturally would return.

I'm reasoning based on my understanding of the ignition system which is limited, and the knowledge I gained from one of my favorite subjects, physics. It's highly unlikely all 6 coils went bad at once, and having heard such a recommendation before (due to uncertainty), I wouldn't consider a technician that suggested I replace all of my ignition coils, before replacing the crank sensor on an 85k motor (which is cake work for ignition coils) my friend. That's not the kind of Black Friday I'm interested in.

You can lose 3 ignition coils and keep driving. Lose your only crank sensor and you stop dead in your tracks. I had a similar incident to yours in our Nissan early last year, which has over 100k miles on it. Stopped at a light, the car sputtered and stalled, (right next to a mobile auto mechanic) it had never done that before. I replaced the crank sensor within the following 2 weeks and it has not done it since. The coils had already been replaced the previous year as they started going out one by one. I also replaced the crank sensor in the CTS not long after the Nissan as preventive maintenance.

I don't know what caused the trouble you have encountered, it may not be the crank sensor, but it is a crank sensor symptom and a common one at that.

I had that sensor go out in my 2001 Kia Sedona mini van, this time the symptoms seem different, but who knows, it could be. Is there a "test" that a mechanic can run to verify the quality of the sensor or is it just a replace and see type thing?

 

[Long]

It doesn't offer me an "edit" option

You're either posting on a smartphone or an abbreviated version of the forum then.

 

[Joseph Upson]

I had that sensor go out in my 2001 Kia Sedona mini van, this time the symptoms seem different, but who knows, it could be. Is there a "test" that a mechanic can run to verify the quality of the sensor or is it just a replace and see type thing?

They can scope it (scan tool/oscilloscope) and watch for abnormal variations in the digital signal. I'm not being hard on the individuals servicing your car. I spent many years in the industry and I've heard that recommendation several times (replace all of the coils) and in my opinion it is more therapeutic for the tech, than it is for the symptoms. The crank sensor is not something I would waste much time with at the 100k mile mark. I would replace it automatically at that point.

 

[Joseph Upson]

You're either posting on a smartphone or an abbreviated version of the forum then.

I believe it is because he does not have enough posts. I encountered that scenario also from my desktop at one time.

 

[Long]

I believe it is because he does not have enough posts. I encountered that scenario also from my desktop at one time.

I don't recall being unable to edit as a noob, but perhaps.
I do know the edit feature becomes unavailable after a period of time from the original post (like 7-10 days IIRC).

 

[tinman]

What about the recall on the TB?