Car is bouncing/rumbling (2003 Buick LeSabre custom)

[thisizit32]

When I'm driving, My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.
I can even see my grocery bags in the back seat shaking a bit even while I'm at a red light.
Been over a week.
All fluids are good

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

 

[HotZ28]

My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

Are there any earthquakes happening where you are located? 🙄 Is the ignition switch in the ON position when you here this "rumbling" noise? Where is the "rumbling" noise coming from, the front, or the rear of the vehicle? We need more information in order to help. 😉

 

[thisizit32]

Are there any earthquakes happening where you are located? 🙄 Is the ignition switch in the ON position when you here this "rumbling" noise? Where is the "rumbling" noise coming from, the front, or the rear of the vehicle? We need more information in order to help. 😉

It isn't so much just a noise...the whole car bounces. I even had a bag in the backseat and when I was sitting still I can see the bag shaking.

 

[HotZ28]

It isn't so much just a noise...the whole car bounces. I even had a bag in the backseat and when I was sitting still I can see the bag shaking.

Is the ignition switch in the ON position when you here this "rumbling" noise? Where is the "rumbling" noise coming from, the front, or the rear of the vehicle? Bag shaking in the rear seat which side? Please answer all of the questions asked, otherwise we are going down a one way street, headed the wrong direction! 🤔

 

[BossHog39]

sounds to me like you lost one coil pack. the coils on the 3800 fires two cylinders so losing one coil you lose two cylinders so it would be running on 4 cylinders. have you got power issues?

 

[HotZ28]

We don't know yet if the engine is running or not, when this "rumbling" is taking place? The OP needs to expand & clarify some of the questions already asked?

 

[thisizit32]

sounds to me like you lost one coil pack. the coils on the 3800 fires two cylinders so losing one coil you lose two cylinders so it would be running on 4 cylinders. have you got power issues?

Ohhh, that could be. I have no power issues though, but I forgot to mention, the diagnostic computer said cylinder 5 misfire, but I changed the spark plug for #5 (+2 others) but still happens.
Also even before and after I changed it, it doesn't run steadily bumpily, but most of the time.

 

[thisizit32]

We don't know yet if the engine is running or not, when this "rumbling" is taking place? The OP needs to expand & clarify some of the questions already asked?

Yes, I mentioned it's running, even when I'm at red lights as I said

 

[thisizit32]

Is the ignition switch in the ON position when you here this "rumbling" noise? Where is the "rumbling" noise coming from, the front, or the rear of the vehicle? Bag shaking in the rear seat which side? Please answer all of the questions asked, otherwise we are going down a one way street, headed the wrong direction! 🤔

Yes, ignition switch is on (do you mean something else?, as I stated it happens while the car is running)
The bag that was shaking was in the backseat driver side, but it feels like the whole car.

 

[HotZ28]

So that sounds like the engine is still misfiring. Do you have the same P0305 code? Did you change the ignition wires or test the coil?
How to Test Coil Pack

 

[thisizit32]

So that sounds like the engine is still misfiring. Do you have the same P0305 code? Did you change the ignition wires or test the coil?
How to Test Coil Pack

Yes the same code is still there even after erasing it.
I didn't change the ignition wires or test the coil, but thanks for the instructions, I'll check that out!

 

[thisizit32]

Yes the same code is still there even after erasing it.
I didn't change the ignition wires or test the coil, but thanks for the instructions, I'll check that out!

So that sounds like the engine is still misfiring. Do you have the same P0305 code? Did you change the ignition wires or test the coil?
How to Test Coil Pack

Hi HotZ28, the same problem is happening but something worse to go with it. I was driving uphill and I couldn't even go the speed limit...so I tested the codes and the first code isn't there anymore p0305, but now a new code: P0201 injector circuit / open cylander 1. Any ideas?

Yes the same code is still there even after erasing it.
I didn't change the ignition wires or test the coil, but thanks for the instructions, I'll check that out!

When I'm driving, My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.
I can even see my grocery bags in the back seat shaking a bit even while I'm at a red light.
Been over a week.
All fluids are good

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

*Update*
the same problem is happening but something worse to go with it. I was driving uphill and I didn't have enough power to even go the speed limit...so I tested the codes and the first code isn't there anymore p0305, but now a new code: P0201 injector circuit / open cylander 1. Any ideas

When I'm driving, My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.
I can even see my grocery bags in the back seat shaking a bit even while I'm at a red light.
Been over a week.
All fluids are good

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

*Update*
the same problem is happening but something worse to go with it. I was driving uphill and I didn't have enough power to even go the speed limit...so I tested the codes and the first code isn't there anymore p0305, but now a new code: P0201 injector circuit / open cylander 1. Any ideas

When I'm driving, My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.
I can even see my grocery bags in the back seat shaking a bit even while I'm at a red light.
Been over a week.
All fluids are good

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

 

[thisizit32]

sounds to me like you lost one coil pack. the coils on the 3800 fires two cylinders so losing one coil you lose two cylinders so it would be running on 4 cylinders. have you got power issues?

*Update*
the same problem is happening but something worse to go with it. I was driving uphill and I didn't have enough power to even go the speed limit...so I tested the codes and the first code isn't there anymore p0305, but now a new code: P0201 injector circuit / open cylander 1. Any ideas

 

[John Canon]

1. Sounds like it is getting worse.
2. It could get more worse.

 

[HotZ28]

Part 2 -How to Test the Fuel Injectors (GM 3.8L)

Page 2 of 3: How to Test the Fuel Injectors (GM 3.8L). All Fuel Injectors have a specific internal resistance that can be measured in Ohms mode on a Multimeter. You won't always have a specific BAD Fuel Injector Code.

troubleshootmyvehicle.com

 

[thisizit32]

When I'm driving, My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.
I can even see my grocery bags in the back seat shaking a bit even while I'm at a red light.
Been over a week.
All fluids are good

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

I purchased an ignition control module thinking that was it but it made no difference

 

[ulycyc]

Step back for a second. First pull all the plugs and see which one is fouled if any. Then concentrate on that cylinder. Make sure that plug wire, coil and injector test good. If ok then do a compression/leakdown test. Let us know what you found.

 

[thisizit32]

When I'm driving, My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.
I can even see my grocery bags in the back seat shaking a bit even while I'm at a red light.
Been over a week.
All fluids are good

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

UPDATE
mechanic said:
I strongly urge you to consider testing first. There are a few things in that circuit that can cause that code. If you choose not to test and install that is your choice, but you would pay either way.

 

[thisizit32]

When I'm driving, My car started rumbling, just kind of bouncing / rumbling even while I'm sitting still.
I can even see my grocery bags in the back seat shaking a bit even while I'm at a red light.
Been over a week.
All fluids are good

It's a 2003 Buick LeSabre custom.
Does anybody have any ideas?

A non professional mechanic said it's prob a fuel filter...but that wouldn't be it, would it? Because the car prob wouldn't run at all if that's the issue?