2004~2008 Mazda3 acceleration problems

Okay so I have been looking everywhere I can for someone having the exact same issue and I can’t find anything on it. So I have a 2005 Mazda 3 2.3L automatic 110,000miles. I have checked the MAF, Fuzes, coil packs, spark plugs, O2 sensors changed, air filter. The car has zero trouble codes but. About 75% of the time when I’m driving. It will stop accelerating and if I give it gas more and more it will pop and bang and start dropping rpm and if I left of the pedal and get back into it it’ll do the same thing until I mess with it enough and finally it will lightly accelerate again. It does it more when it’s warm but it will do it when cold. If anyone has had this same issue I would love some guidance
 
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2014 Mazda3 S GT auto, 2008 MX5 6-speed
How old is the timing belt? Is it a belt or chain? How about the fuel injectors? Have they been checked?
 
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2003 protege 5
My sister has an 05 with a similar issue. She says it won't go when trying to leave from a dead stop. Very inconsistant issue and usually happens once warmed up and driving for a few minutes also not throwing any codes. After checking many things I had her try and shift into manual sport mode. The car showed 1st gear in drive but when slammed into manual mode it showed 2nd. A quick flick of the wrist put it into 1st and away it goes. Had a trans shop check tranny, fluid and filter change but couldn't duplicate the issue. Then I am informed the TCM which is built into the ECM has a history of failing. And they are not being remade. So we are toying with the idea of trying a refurbished/updated unit to see if that fixes the issue. 2007 and up have a seperate TCM I believe but 04 and 05 are built into the ECM.
So in summary - try sport mode and see if the issue goes away
 
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My sister has an 05 with a similar issue. She says it won't go when trying to leave from a dead stop. Very inconsistant issue and usually happens once warmed up and driving for a few minutes also not throwing any codes. After checking many things I had her try and shift into manual sport mode. The car showed 1st gear in drive but when slammed into manual mode it showed 2nd. A quick flick of the wrist put it into 1st and away it goes. Had a trans shop check tranny, fluid and filter change but couldn't duplicate the issue. Then I am informed the TCM which is built into the ECM has a history of failing. And they are not being remade. So we are toying with the idea of trying a refurbished/updated unit to see if that fixes the issue. 2007 and up have a seperate TCM I believe but 04 and 05 are built into the ECM.
So in summary - try sport mode and see if the issue goes away
It is better in sport mode but it will still do the same thing even in manual mode unfortunately.
 
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2010 Mazda 5 Sport
Could be a weak fuel pump. A car that runs fine until you accelerate is often a Throttle Body issue or a fuel pump.
 
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Could be a weak fuel pump. A car that runs fine until you accelerate is often a Throttle Body issue or a fuel pump.
Runs fine when accelerating but randomly will decide it doesn’t want to accelerate. I’m thinking the transmission is doing something weird. Possibly the TCM
 
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2003 protege 5
That is what a tranny shop told us too. The TCM starts to fail and the trans does weird things. The TCM is built into the ECU for 04 and 05 models. Not sure about 06. The 07s and up are a seperate unit from what I have been told. The replacement ECUs for the 05 years are no longer made both aftermarket and from mazda. We are toying with the idea of getting a refurbished/repaired one from a company in New York. I was told this is a crap shoot however...
 
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Northeast
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2020 CX-5 Tour
I always start by doing diagnostic testing, instead of just throwing parts at a problem. But as always, your vehicle, your choice.
 
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2010 Mazda 5 Sport
Is it not accelerating or not shifting?

I thought a bad TCM would exhibit erratic shifting or lack of shifting. Once in a gear, shouldn't the car still accelerate even if the TCM is bad?

Did you pull codes?

I just don't see how the TCM would make the ECU "pop and bang" and run poorly.

I would clean the throttle body and do a fuel pressure check.
 
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I have checked everything there is to check and it doesn’t throw any codes. Everything fuel, air and spark related. It just doesn’t want to accelerate sometimes and if you try to just give it more gas it starts dropping rpm and backfiring almost like it’s getting the fuel but not the air or something is putting a huge load on the engine not letting it rev. Sometimes it drives just fine and randomly at the next stop light it’ll just decide it doesn’t want to accelerate and I have to sit there off and on with the throttle until it wants to go
 
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18 Mazda CX5 AW
I have checked everything there is to check and it doesn’t throw any codes. Everything fuel, air and spark related. It just doesn’t want to accelerate sometimes and if you try to just give it more gas it starts dropping rpm and backfiring almost like it’s getting the fuel but not the air or something is putting a huge load on the engine not letting it rev. Sometimes it drives just fine and randomly at the next stop light it’ll just decide it doesn’t want to accelerate and I have to sit there off and on with the throttle until it wants to go
I'm a DIY myself but go to my local mechanic if i can't pinpoint the problem.

It could be anything from bad/clogged sensor(s), worn clutch, clogged fuel or air filters, TCU/TCM, ECU/ECM, low fluid, engine, ignition, etc.

EDIT: looks like you checked or replaced alot of components already. I'd just take it to your local mechanic and let him pinpoint it. Will be $50-100 well spent. Also, did you test your MAF with a VM/DMM ? you replaced the O2's but the MAF is 18 years old? You sure it's still good? Last time fuel filter changed?

Like Edmaz said above, try your diagnostics first...
Or just take it to your local garage and see if they can pinpoint the problem.

My process is try to diagnose the problem and then fix if easy. If can't locate the problem, then take to my mechanic. If he determines it's something complex or I'm too busy at work, i just let him fix it. Otherwise, i just fix at home.

Any lack of acceleration problems I've had on other vehicles was due to bad/defective/clogged sensors or a bad ECM/TCM. Refurbished EMC/TCM worked fine.

But I always properly maintained my vehicles.

If you're not the first owner or if the vehicle wasn't properly maintained and driven, could be clutch, fluid, filters, ignition, etc.
 
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2003 protege 5
I agree with troubleshooting and I understood the OP to have done much of that. I was suggesting to check the trans shifting functions manually because our issue is the trans not shifting properly and not downshifting completely to a complete stop. I have heard many versions of this problem and I was trying to rule out his auto from not shifting correctly. Much like trying to accelerate in a manual in 5th or take off from a dead stop in 2nd or 3rd. They dont accelerate well, bog down and show other symptoms similar to an unhappy engine. All that being said I agree with Jack Rabbit and think a live data scan would be best if you have done all the troubleshooting and have 0 TCs to go off. Even if youre just paying for the scan it will point you in the right direction to make repairs yourself.
 
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