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RPM flutter on deceleration after induction cleaning

2004 Mazda 3 (4-door with hatchback) automatice with option for semi-manual transmission : With an oil change last week I had the dealer talk me into an “induction cleaning” ; ever since I got my car back I noticed when I coast to a stop that when the car decelerates fro 40 to 30 that the RPM gauge flutters back and forth 3X between 1000 and 1,500 RPMs. There is no computer engine light on but why would this start all the sudden ? Its causing a back-n-forth pull on the car every time I come to a stop if I have driven over 40mph … it doesn’t matter if I use the break or coast to a stop but when I coast it flutters 3 or 4 times ; when I use the brake it flutters 2 times.

Can you describe the technique and product the Dealer used for induction cleaning

Did it include a throttle body cleaning?

Normally the only difference noticed with a induction cleaning is a loss of money,seriously.

Now if the throttle body was cleaned you may notice a smoother feel with the gas pedal

I wonder if the Dealer did a Throttle Position Switch cleaning, If they did, possibly some damage to the TPS contacts.

Give the underhood area a good look (check for disconnected or broken wires or vacuum lines), a trip back to the Dealer is in your future, get them to ride with you so they can feel the problem themselves, prepare yourself for the dealer to try and sell more work (diagnostic time also) in regards to your new problem.

Thanx oldschool. Well I just got a call from the dealer because I dropped my car off today and I read him some of your reply and he said “yes” they originally did a throttle body cleaning (I definitely felt a smoother feel to the gas pedal after picking it up). He said they also just today changed the whole throttle body assembly today, which he said included the TPS contacts, but unfortunately it did not fix the problem. They are not charging me for that. He’s not sure what to do next so he called me to say he’s going to try reprogramming the computer.
I think I’m sorry I ever had them do this induction cleaning. Honestly I’ve made it my practice to get bigger maintenance items done twice a year to spread out the cost so when I took it in a couple weeks ago for my regular oil change I asked "What other important maintenance item should I have done ? " They recommended the induction cleaning (which obviously you would not have). Hopefully I will get past this problem without them charging me anything and more importantly they didn’t damage my car permanently (I just paid it off 5 months ago so that would be a major drag).

I’ll keep you posted on their progress but any other leads would be appreciated. I was reading on the CarTalk website that the throttle sensor might be the problem ? Is that part of the throttle body assembly that they replaced ? Also I was wondering if I pose the same question to you : What other preventative maintenance things should I do ? (other than the 4 new tires, new air filter, new battery and the a transmission & radiator flush I have already done what else should I consider getting done to maintain my car ? (For example, I have 55,000 miles on my car so at what mileage should I change the spark plugs or timing belt ?)

Make a distinction between “Dealer recommended services” and what is recommended by the manufacture.

Stay away from services labeled “flushes” except for brake fluid,I go for every 2yrs many will condider this excessive.

Keep on top of the timing belt change (look in the service manual if even required) Many times a water pump and timing belt tensioner are done at the same time,this is normal) it is advantageous to combine the coolant exchange(not flush) with the timing belt/water pump work, but don’t delay a timing belt because you want to schedule the coolant exchange at the same time.

Be suspect of batterys over 2 yrs old (many will get better servive) but keep it in mind.

I don’t like leaving sparkplugs in over 30,000(not because they are worn out but because they can sieze in the head).

Things that can come up are oxygen sensors and catalytic converters (covered up to 8yrs 80,000 miles)

We get many posts from people that have trouble fueling their cars(not your model specfically) don’t try to put every last bit of gas in.

Stay on top of tire rotations and when they do a tire rotation they can do a brake inspection, if they say you need brake pads make them show you (a comparison to a new pad is very helpful but seldom possible) When you do need brakes I think it is better to get new rotors, reguardless, get the best quality, not best price,this is just a personal opinion as many see no problem in “turning the rotors”

Stick with the oil type and grade recommended, no addatives, no chemical engine flushes.

It is really hard to tell if a car needs new struts by bouncing the car,if they are not leaking its pretty much up to a mileage decision, I’will put 90,000 as a minimum for front struts on your car, second opinions on suspension work have great value.

Old school … you have been a wealth of information and I can’t thank you enough.
Good news was that I picked up my car FREE OF CHARGE from the dealer yesterday because turned out simply updating the computer firmware of the car fixed the problem. I wished they would’ve tried that first before replacing the whole throttle assembly but I guess that shouldn’t hurt anything but I’m not a fan of fixing what isn’t broke.

Interesting I forgot to note I already had the front brake pads & rotors replaced a couple years ago so I’m glad I got new rotors. But I have never had the brake fluid flushed so I’ll take your advice and put that next on the list. I have always used the 5W/20 oil recommended in my manual and my car has not had a lot of problems but I know at 55,000 miles things can start happening. Thanx for all the good info. I’m going to print it out and check my manual … can’t thank you enough for your advice which I will heed in the future
:slight_smile: sincerely JaniceRPMflutterNOMORE

Hello, my 2004 Mazda6 i is having the exact same problem only I haven’t had anything done to the engine directly. However, my battery was bad and needed a jump to go get it replaced; the problems started the next day. Could it be that something was moved or damaged when the battery was being replaced or perhaps changing the battery reset the computer? I can’t find anything else on the internet about a firmware update and am afraid that the dealer with try to make up other problems or charge an obscene amount just to look at it. Is there something in particular that I should be looking for in the engine or how can I find out if I need a firmware upgrade?

Thanks in advance.