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I haven't seen this problem listed here, at least not under coil specifically, so here's a new thread.

Mrs. Blue came home yesterday & said the check engine light was on- the Acadia was running rough. We have a little over 16K miles at this point.

I made a test drive & noted that while the light was on, it ran fine- made a couple of 6800 RPM shifts during the test drive.

Anyway, I made an appointment for this morning. On the way there, the light would flash when going up a hill & the motor would run rough. I noted avg MPG dropped to 16.8. I was at the dealer a little over an hour & the tech said it was a bad coil. They had one in stock and I was good to go.

No more light, and the engine ran smooth all the way home- avg MPG was back up to 17.2 just in the short 20 mile trip.

While I'm disappointed the coil failed so soon, it would be great if all services went this well.
 

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Blue_2009_SLT2 said:
I haven't seen this problem listed here, at least not under coil specifically, so here's a new thread.

Mrs. Blue came home yesterday & said the check engine light was on- the Acadia was running rough. We have a little over 16K miles at this point.

I made a test drive & noted that while the light was on, it ran fine- made a couple of 6800 RPM shifts during the test drive.

Anyway, I made an appointment for this morning. On the way there, the light would flash when going up a hill & the motor would run rough. I noted avg MPG dropped to 16.8. I was at the dealer a little over an hour & the tech said it was a bad coil. They had one in stock and I was good to go.

No more light, and the engine ran smooth all the way home- avg MPG was back up to 17.2 just in the short 20 mile trip.

While I'm disappointed the coil failed so soon, it would be great if all services went this well.
Hi Blue,
Sorry to hear you had a problem with the Acadia. I wanted to point out the flashing check engine light. When the light is flashing you are in danger of damaging components in the emissions system .You should pull over until the light stops flashing or restart if you feel confident it will restart. If the check engine light is on steady that means attention is required by it can still be driven but it will probably be in reduced power mode.
I had an engine misfire code in my 3800 engine that turned out to be a bad injector. The check engine light started flashing and I pulled over and it stopped. I was able to get it home without it flashing again.

It is real easy to damage the cat/converter if you continue to drive with a flashing check engine light. I just wanted to make sure other forum members know this information.

Bobby
 

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Discussion Starter · #3 ·
Thanks for the info. Seems odd it was not flashing continuously, only under higher load. In any event, we had the defect corrected in < 24 hours. I'm really pleased with the dealer getting us in right away & not sitting on it all day when it was there.
 

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Blue_2009_SLT2 said:
Thanks for the info. Seems odd it was not flashing continuously, only under higher load. In any event, we had the defect corrected in < 24 hours. I'm really pleased with the dealer getting us in right away & not sitting on it all day when it was there.
Interesting - I've seen many check engine lights illuminated but none ever flashing. Of course cat converter covered for many miles anyway
 

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mikemu said:
Interesting - I've seen many check engine lights illuminated but none ever flashing. Of course cat converter covered for many miles anyway
The flashing check engine light is a sign of a misfire. It is best to slow down,avoid hills,hard acceleration when this occurs. It might make the light stop flashing and stay on steady meaning it is safe to keep driving. Now you say the cat is covered for many miles. This is true. If you bring in you vehicle with a trashed cat converter and the dealer connects a TECH II scanner and if they are able to see how long it was driven with the flashing check engine light I don't know if the warranty would apply. GM will be watching especially in these times. So just keep that in mind.

Bobby
 

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DeForger said:
The flashing check engine light is a sign of a misfire. It is best to slow down,avoid hills,hard acceleration when this occurs. It might make the light stop flashing and stay on steady meaning it is safe to keep driving. Now you say the cat is covered for many miles. This is true. If you bring in you vehicle with a trashed cat converter and the dealer connects a TECH II scanner and if they are able to see how long it was driven with the flashing check engine light I don't know if the warranty would apply. GM will be watching especially in these times. So just keep that in mind.

Bobby
All good info and great to learn something new.
 

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Learn something new everyday ---Thanks for the great info.

HAPPY JULY 4th EVERYONE, Drive safe and keep the Acadias in one piece , let the wives drive!!!!:cheers: :beer:
 

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Blue_2009_SLT2:

It seems that you were right on the money about why my engine light was coming on. I wasn't able to pick it up until last Saturday (I didn't get the call they placed late on Friday), so when I talked to the Service Manager on the phone and asked him what the problem was, all he said was" "You had a bad injector. We replaced it but discovered that the plugs were fouled and we had to replace a spark plug. And the coil . . . " He went on with some other information that I could not understand (I am somewhat mechanically challenged with the new cars). ???
Besides, there was outside noise that prevented me from hearing everything he said (Well, I need some kind of excuse, don't I? ;D)

So, I am going to rely on your collective expertise to make sense out of what this GMC double-talk means: :confused:

"Cust(omer) states the SES light is coming on and flashing at times. OnStar cannot give code.
Found code P0300 stored. Removed spark plug and found fuel fouled. Tested ignition coil and found ok. Performed fuel injector testing and found the #2 fuel injector dumping excessive fuel into #2 cylinder.
Replaced the #2 injector and plug. Rebuilt 2 remaining injectors. Cleared Code and road tested. Now found misfire on cylinder #4. See Line 4 for diagnosis and repair."


Further down on the page he made this entry:

"After repair of Line 1 found misfires on cylinder #4, found the #4 ingitiion coil weak and causing misfire, replaced the #4 ignition coil.


There is a second page to which they make reference but it was not among the papers they gave me. I am going back to demand the remaining portions of the service receipt. :mad: But you should note the following difference in the performance of the Acadia -

Although the engine light does not come on, the idle seems to be just a little off. I noticed that the acceleration is slower. When stopped at a light with my foot on the brake or sitting at idle, the engine is real quiet with no vibration, and then it changes to a very low frequency rumble that you can hear and feel, and then it goes back to being quiet again I'm not sure if it is the air conditioning or other systems drawing power). Sometimes when sitting at a light the engine rumbles and almost seems like it is going to shut down (like it did before I took it in). It has been responding pretty well overall, but it is just different somehow. The vehicle shift points seem to have changed. Now I have to really "punch it" to get it up to 55 mph or more. It seems it takes longer to cover a quarter mile, and at a lower speed. Once it gets into a lower gear it responds well, even quicker than before, but I'm not sure it that is good or bad.[/color]
I'm not certain if this is the result of a "flash" they performed (It was not mentioned on the service receipt and I failed to request it).

And one other question: Does replacing the coil, an injector and plugs require service personnel to "pull the engine"? And what does "rebuild" mean in regard to an injector? [/color]

Perhaps there is some reasonable explanation, and I am not sure if this is all normal or what. I would like to be armed with a better understanding of what may be wrong and what was not proper BEFORE I go back and complain (and see the remaining information on the service receipt).

Hope you guys can help.

Moderators: This topic may be in the wrong area because I began posting about this issue under a different heading. Blue merged it but I can't find the correct location. Please merge this posting to where it is appropriate. Thanks.[/color]
 

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Discussion Starter · #9 ·
detnick,
I've been away most of the week & just read your post.

I'll take a shot at your questions:
Code P0300 is a random/multiple cylinder misfire. OBD2 codes can be found here.

GM labels cylinders in an odd-even bank system. #1 is usually the front left cylinder when looking at the top of the motor from above, and the front is where the alternator, water pump, etc. are located. The middle cylinder is #3, and the rear one #5. On the other side, you have 2-4-and 6 in the same order.

Here is an illustration that does better at this than my ramblings:


If the Acadia uses this layout (I'd have to pop the engine cover to see this, and right now ours is resting after a long trip), this means the #2 and 4 cylinders are on the side next to the firewall. Depending on access, these may have required the engine to be removed. Usually when it is on a lift, you can access them from underneath, but this is a drawback to the typical FWD design.

The tech went through a diagnostic process as he should have. Internal combustion motors need compression, fuel, and spark to run. While it is rare for an injector to fail so soon (I am still using some from various year GM products in my several cars w/ transplanted motors), it can fail, just like my coil did. It's interesting the tech "rebuilt" the other two injectors on that side, since this is a direct injection motor. I've never looked at the specifics, but figured the injectors did not sit in a rail like they do on my V8 motors. I suppose his idea was any contaminants could have affected those as well, but if that is the case, they could have affected the remaining three also (more on this later). I am under the impression that rebuilding an injector is a semi-specialized task and this is done by specialty shops, such as RC Fuel Injection (loads of fuel injector stuff there). I doubt a dealer would have the machines needed to take an injector apart & spare parts on hand to rebuild it, plus I'd think the warranty would pay to remove & replace as he did with #2. Perhaps he cleaned them?

As far as the engine running differently, figuring there were some contaminants in the fuel and they lunched one injector, they could have affected the remaining five. If the tech attended to injectors 2 (replaced), 4, and 6 ("rebuilt"), then he didn't do anything with 1,3, and 5. There could be a flow problem developing in one of those, and your light may come on again after a while.

By all means express your concern to the service dept. Get the remaining info, techs generally do not do anything they are not paid to do, since warranty work is a lower paying task than the customer pay type of job. It seems odd they would have reflashed the system and not reflected this on the repair order.

Hope this helps with what you needed to know.
 

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Blue:

Thanks for taking the time to give me instruction on Injectors 101. I had no idea it was that complicated, but then again, I didn't get the sense that the Service Manager was really particularly concerned about my issues. As you point out, if bad fuel or other contaminants were responsible for the bad injector, it stands to reason that the others would be affected. In fact, as you also stated, why would he only replace one, "rebuild" two others and not address the last three? ??? ::)

GM has this questioneer thing going where they almost beg you to give them the highest rating for satisfaction. They give you one when you pick up your vehicle and another one will be forthcoming either in the mail or on-line. Either way, I am going to get to the bottom of this. I'm hoping upon hope that this will turn out to be a minor thing and that the problem is fixed. But, honestly, I am not very optimistic given recent history with dealerships and their personnel. :mad:

After reading your posting, I got to wonder what could have caused the injector to go bad. I have used Shell (the preferred fuel with the better additives) since I had the Acadia, and only strayed One Time when Shell was not available (I used some Amoco, but not even a tankful). Right after that the engine started to have problems. Do you think it's possible it could have somehow been because of the change in fuel (I hope I'm not being paranoid)? :confused:

Anyway, thanks again for your invaluable help and guidance. What the saying? "Being forwarned is being forearmed."
Because you took the time to provide me with this info, I am much better able to argue my case with these guys at the dealership. :thumb:

Thank you. I'll keep you up to date on any and all progress (or lack thereof). ;)
 

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Discussion Starter · #11 ·
detnick said:
...After reading your posting, I got to wonder what could have caused the injector to go bad. I have used Shell (the preferred fuel with the better additives) since I had the Acadia, and only strayed One Time when Shell was not available (I used some Amoco, but not even a tankful). Right after that the engine started to have problems. Do you think it's possible it could have somehow been because of the change in fuel (I hope I'm not being paranoid)? :confused:
In my experience, often the cause of a problem is usually related to something that has taken place or changed just prior to the problem developing. Could be the Amoco station had some bad gas, or it could be an entirely random event.

Glad you found the info helpful & hope you get it back to 100%.
 

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Blue_2009_SLT2:

I took your advice (along with your detailed information) and confronted the Service Manager (actually it was over the telephone, but my intent and my insistance on honest answers was apparent). I explained my concern about all of the injectors possibly being bad due to bad fuel or other contaminants and indicated that I was not satisfied with the way the engine was performing, the continued "loping", the sluggish acceleration and the changed shift points. I also inquired about his ability to either "clean" the injectors, replace them or rebuild them.

What he told me was surprising: He stated that he observed the problem following the diagnostics and replaced the injector because it had gone bad. He did not know the origin of the fouling of the injector or what the contaminate was. He stated that he checked and determined that the last three injectors had not been adversely affected and that the two he did rebuilt were actually rebuilt - using a "kit" that GM provided for that very purpose.

He went on to say that he discovered the malfunctioning coil and replaced it as well. He assurred me that if I discovered any additional problems that he would not hesitate to examine and repair the vehicle until it met my satisfaction.

He indicated that the change in shift points was due to the fact that it had been tested and driven by members of the Service crew and that it should go back to the way I prefer after about a week because it is a "learning" transmission that stores info on how an individual drives the vehicle (I either read or heard about this before on Acadiaforum.net, I just don't know exactly where). He also said that he did not flash the trans because it would not be necessary in the 2009 model since changes had been made to the trans in the new model year. He did agree to make necessary changes if required in the future.

Bottom line: I am going to wait about a week or so and determine if the problem is solved. I still get the occasional low RPM "lope" and low frequency vibation when waiting at a light or when slowing. Sometimes it "seems" as if the RPM's are so low that it might shut off. But it might be just the occasional alternator and/or air-conditioning systems going in and out.

I'll keep you advised.

Again, thanks for the help.
 

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There is a transmission flash available for 2009 Acadias built Oct 08 and earlier. I had it done to mine a few weeks ago and it is a marked improvement. My dealer didn't know anything about it either but I had brought along the TSB number (#09-06-04-019) just in case so they were able to look it up.
 

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detnick said:
Blue_2009_SLT2:

I took your advice (along with your detailed information) and confronted the Service Manager (actually it was over the telephone, but my intent and my insistance on honest answers was apparent). I explained my concern about all of the injectors possibly being bad due to bad fuel or other contaminants and indicated that I was not satisfied with the way the engine was performing, the continued "loping", the sluggish acceleration and the changed shift points. I also inquired about his ability to either "clean" the injectors, replace them or rebuild them.

What he told me was surprising: He stated that he observed the problem following the diagnostics and replaced the injector because it had gone bad. He did not know the origin of the fouling of the injector or what the contaminate was. He stated that he checked and determined that the last three injectors had not been adversely affected and that the two he did rebuilt were actually rebuilt - using a "kit" that GM provided for that very purpose.

He went on to say that he discovered the malfunctioning coil and replaced it as well. He assurred me that if I discovered any additional problems that he would not hesitate to examine and repair the vehicle until it met my satisfaction.

He indicated that the change in shift points was due to the fact that it had been tested and driven by members of the Service crew and that it should go back to the way I prefer after about a week because it is a "learning" transmission that stores info on how an individual drives the vehicle (I either read or heard about this before on Acadiaforum.net, I just don't know exactly where). He also said that he did not flash the trans because it would not be necessary in the 2009 model since changes had been made to the trans in the new model year. He did agree to make necessary changes if required in the future.

Bottom line: I am going to wait about a week or so and determine if the problem is solved. I still get the occasional low RPM "lope" and low frequency vibation when waiting at a light or when slowing. Sometimes it "seems" as if the RPM's are so low that it might shut off. But it might be just the occasional alternator and/or air-conditioning systems going in and out.

I'll keep you advised.

Again, thanks for the help.
I've read various posts regarding the "learning transmission" as well, and the general consensus, and supported by who seems to be the tranny expert here, is that its BS.

Also note as jh46 said just above: There is a tranny update available. Mine was built after yours (oct 08), and i had the update performed. I agree its an improvement, although my gas mileage may have suffered a couple mpg (not sure yet).
 

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I am not convinced the trans learns anything; I think it's inclined to shift depending on a lot of variables; I noticed the trans a few times on our trip-it would act differently after 3 straight hours of 70+
 

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I find myself agreeing with you guys about the trans. In the past few days (since last Saturday) the shift points have changed almost daily. This morning on the way to work I would step on the accelerator and it would almost peal off the line like I was running a quarter mile track! Then when I reached just above 50 mph I was running just under 1000 rpms like it was cruising. Then suddenly it would start groping for the right gear as it strained above 50 mph.

When I first took delivery I made it a point to try and "ignore" all the reviews, postings and related data that I found at Acadiaforum.com. I didn't want to get my new car and pre-judge it. As a result, I didn't really notice any lags in performance or bad shift points (well, maybe only occasionally, but who's counting?). I decided that generally if it performed well, got me to my destination safely and continued to function comfortably, then I could live with the dreaded "tranny problems". Now, with the radio off and no one in the Acadia but me, I find myself listening and watching the shift points and how it accelerates.

Actually, the quick and seemingly responsive shifts in the last days (and similar responses in the higher RPM ranges) have changed my attitude for the better, making me feel like this is the way I prefer it to work. But given the fact that this trans is so unpredicable, then I am certain that it will not continue. Too bad it can't be programmed to stay this way.
 

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detnick said:
I find myself agreeing with you guys about the trans. In the past few days (since last Saturday) the shift points have changed almost daily. This morning on the way to work I would step on the accelerator and it would almost peal off the line like I was running a quarter mile track! Then when I reached just above 50 mph I was running just under 1000 rpms like it was cruising. Then suddenly it would start groping for the right gear as it strained above 50 mph.

When I first took delivery I made it a point to try and "ignore" all the reviews, postings and related data that I found at Acadiaforum.com. I didn't want to get my new car and pre-judge it. As a result, I didn't really notice any lags in performance or bad shift points (well, maybe only occasionally, but who's counting?). I decided that generally if it performed well, got me to my destination safely and continued to function comfortably, then I could live with the dreaded "tranny problems". Now, with the radio off and no one in the Acadia but me, I find myself listening and watching the shift points and how it accelerates.

Actually, the quick and seemingly responsive shifts in the last days (and similar responses in the higher RPM ranges) have changed my attitude for the better, making me feel like this is the way I prefer it to work. But given the fact that this trans is so unpredicable, then I am certain that it will not continue. Too bad it can't be programmed to stay this way.
FWIW sounds like to me your tranny ECM is shot or something
 

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Went to start the Acadia today. Got the dreaded "Check Engine Light" on. Contacted OnStar and they ran a diagnostic test. They said it was a misfire and the code was P 0300. The light stays on steady and they said it is okay to drive, but keep the speed down and avoid steep hills. I have only 14,000 miles on the Acadia. My dealer is closed on Saturday, so I will be calling on Monday. My dealer is 35 miles away off a main highway. Don't know if their going to let me drive it there. May have to go to a closer dealer. The adventure begins. :eek:hno:
 

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centurion said:
Went to start the Acadia today. Got the dreaded "Check Engine Light" on. Contacted OnStar and they ran a diagnostic test. They said it was a misfire and the code was P 0300. The light stays on steady and they said it is okay to drive, but keep the speed down and avoid steep hills. I have only 14,000 miles on the Acadia. My dealer is closed on Saturday, so I will be calling on Monday. My dealer is 35 miles away off a main highway. Don't know if their going to let me drive it there. May have to go to a closer dealer. The adventure begins. :eek:hno:
Could call GM 24hr roadside assistance. I had to do that once in my '07 OUTLOOK, power steering leaked (after having the trans leak fixed the dealer forgot to tighten something ::)) and the tow truck co. came with flat bed and off she went.
 

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I've had 2 coil packs replaced on my Enclave in 6 weeks. Same symptoms; flashing CEL then goes off after a few seconds, then when it gets worse the CEL stays on. In my case, go out on the highway, set your cruise to appox. 30 mph, then press and hold the + button to accelerate. If it starts missing, stumbling, and the CEL starts flashing 90% it's a coil pack going or gone bad. Typically, the coil pack goes bad, the injectors get loaded up since the plug isn't firing. Then the injector fails. Go over to the Enclave forum, there's several of us with 09 Lambas and having coil packs go bad. Most of us are around 18-25 thousand miles on them
 
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