Hesitation/stutter up slight hill 2004 Buick LeSabre

[mikerader]

Hello,

I have been experiencing a hesitation or stutter in my cars performance when going up a slight incline. It seems like it might be a stutter or slip when going from overdrive to 3rd gear. Like it may be in the downshift. The problem is I have had electrical issues in the past seem almost exactly like this. I cant quite tell if it is transmission or performance. Upshifts are fine and smooth. If I really press down on gas and force downshift quickly it is fine. Seems to be when giving it slight gas and only up an incline.

2004 Buick Lesabre with 88,000 original miles.
1) I changed ignition module spark plugs and wires 3 months ago for Misfires.
2) I Changed the fuel filter this week.
3) I never had the transmission fluid and filter changed.
4) No engine codes are present.
How can I tell if this is transmission slipping? And if it is can a fluid and filter change help. Transmission fluid level in fine and looks red with no particles in it.

It just seems like it may be a torque converter slip.
Thank you,

 

[ryenie]

there's a few other things that have been mentioned throughout the forum as potentially causing similar issues. The C\V axles can cause a vibration under certain conditions. Replacing plugs and wires seems to get rid of it in my car but only last's for 2 or 3 months before it starts back, doesn't matter brand of wires or plugs, tried oem, same thing. If it were slipping it would hit pretty hard when it caught which would be more of a jerk or slam than a stutter. On the ICM it is recommended that you do a crank relearn procedure which i'm pretty sure requires a tech 2 scanner, if not done it can potentially cause a p0300. I've also seen certain tsb's where the pcm had to be reflashed with different shift points because of torque converter lockup causing vibrations under certain conditions at speeds around 45 mph.

 

[HotZ28]

It sounds like a misfire problem, but you should first find a shop that has a scanner capable of reading individual cylinder misfire and trans codes. A crankshaft relearn is not required when replacing the ICM, only when replacing the Crank Position Sensor (CKPS). For more info on a potential trans problem Click Here.

 

[mikerader]

Picked up Transmission fluid and Filter. It was time anyway to change anyway. A friend told me to watch tach when it happened to see if engine speed dropped during the stutter.

So today I had it in 3rd gear instead of overdrive and I did feel the same hestitation/stutter in 3rd gear and I did not notice a drop in engine rpms. Maybe the gauge was not quick enough to pick it up. But it sure feels like transmission as it really chatters.

I saw a post about replacing spark plugs and they says to take the heat shields off. they can cause shorts. Anyone have any thoughts on this. When I changed the plugs I left the heat shields on.

If the transmission fluid and filter do not help I may have to get the car put on an analyzer rather than keep guessing.

 

[mikerader]

Please disregard previous comments.

1) changed Trans fluid and filter since It was 88K anyway.
2) Had someone look at the pan and he said it looked clean for almost 90 K. Some residue in the bottom of pan and less than a teaspoon of junk on the magnet.
3) shifting a little quicker now but I was able to find a hill and make this fail by just the right amount of gas. It is definitely better after changing the fuel filter.

I suspect the ignition module is cutting out now. Maybe fuel injectors clogged, I will give the fuel injector cleaner time to work.

It is more of a hesitation now where before it was almost bucking.

 

[HotZ28]

Thanks for the update! You may still have a cylinder misfire, which could be the wire, plugs, or the injector. That is the reason I suggested using a capable scanner to be hooked up when the problem occurs that can narrow the problem down to the cylinder. I have installed NEW wires on these same engines that failed with the DIS ignition system within 2-months! If you install silicone coated wires, and keep good clearance between the exhaust header and the wires, you should not need the heat shields. I have the same MSD wires that were installed on my PAU 6-yrs ago without the heat shields, and have never experienced any shudder/misfire on inclines since.

 

[mikerader]

Thank you, this problem has started since I changed the plugs and wires 3months ago. I will pursue this line of troubleshooting.

 

[G-582312]

Thank you, this problem has started since I changed the plugs and wires 3months ago. I will pursue this line of troubleshooting.

I know this is an older thread but was there ever a solution discovered as I'm experiencing the exact same symptoms on my 2004 Buick LeSabre.

 

[Joekow]

Hi.. I have the same problem with a 2003 Lesabre with 160,000 miles. A slight miss only cruising on the highway going up a hill. I have replaced the plugs, wires, coils, coil module, MAF sensor. It does set a p0300 code and occasionally a 02 sensor code. I am thinking of replacing the 02 sensor on the exhaust pipe before the converter.

Anyone seen this before?

 

[LARRY70GS]

Those are misfires. They typically occur under increased load. A good scan tool will tell you which cylinders.

 

[imidazol97]

What wires did you use? Are you using the metal heat shields on the back 3 cylinders?
I took those off thinking they might be doing something.

I used the heavier insulated AC Delco professional wires several years ago to try to fight my
"lean burn" misfire. I assume you put in the proper recommended AC Delco plugs?

I found I would only feel this light misfire when the engine was running at the lower end of
its rpm for full lockup torque converter only in 4th gear. When it was under almost no load
is when it would be running very lean. A slight upgrade and little tip in from the accelerator
and the slight unevenness could be felt. If I tipped in more throttle instead of just a slight
amount for the upslope, the richer mixture didn't have any symptoms.

I ran engine under the same light load conditions in 3rd gear with the torque converter locked up
and the difference in the load would not show the misfire. I inferred that in 3rd gear with TCC
locked up the extra load did not cause a problem.

I recalled that on my 93 leSabre, Buick put in a different chip controlling the torque converter
lockup and some other things to get rid of roughness when the torque converter locked
up early in 4th. The change moved the lockup speed higher by about 5 mph IIRC. Long
time ago. That was enough to avoid feeling the unevenness.

Did you run spark plug wires the way they originally were on the engine to avoid any crossfiring
by induction from adjacent plug wires?

I cleaned injectors. Switched injectors from cylinder to cylinder.

Never really got rid of it.

 

[Joekow]

Thank you for the information. I have replaced the spark plugs and spark plug wires with GM OEM parts. I have swapped out the coils and coil module with OEM parts from my other car that does not have issues. I will get a scanner and see what's going on when the light comes on going up hill. I am thinking of replacing the 02 sensors since it also is setting a 02 sensor code..P0137 maybe it is running lean and going up hill it starts to miss because of that lean condition?

 

[imidazol97]

I never really got rid of mine, but hopefully you are getting a code that needs to be diagnosed.
Maybe that will help yours.

The only thing I didn't try was going one heat range lower on the spark plugs OR
replacing all the injectors. Not worth that much trouble to me.

 

[LARRY70GS]

Make sure it is not running lean. Check for a vacuum leak.

P0137 – Meaning, Causes, Symptoms, & Fixes

Check engine light code p0137 means O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2). Find out how to fix it in this article!

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