I just bought a 04 tl 5at with 56k.

Recently under wot or highspeed driving (above 75) I get a check engine light flashing. The cost scanner says misfire on all cylinders.

I replaced the spark plugs with ngk plugs & the lignition coils.
I also cleaned the egr valve and used fuel injector cleaner.

I'm not sure what else to check at this point.
Any help would be appreciated.

 

bad gas?

 

I use bp & Sunoco 93.

I've used them for years in other cars.

 

OP-I had the same problem with my TL a few years back. There is a TSB for certain vin #'s, I believe most '04's fell under this TSB. I had the ECM/PCM reflashed and it hasn't been back since. I had to pay to have the TSB performed, it was $50.


There is a link to the TSB within this thread below.

https://acurazine.com/forums/3g-tl-problems-fixes-114/all-cylinders-misfiring-839248/

 

Does an acura dealer have to do it?
And is there anyway to check if my ECM was ever reflashed?

If not ill head to acura tomorrow being they are closed today


Thanks for the input. Greatly appreciated.

 

Yes, a dealer will have to do it. You don't want any dumbass flashing your ECU, you want a professional doing it. Acura should be able to look up your VIN# and tell you whether or not the update has been done. You should be able to do it over the phone.

 

Last night I disconnected the battery for about an hour. Drove the car today and it's running perfect.

Definitely think it's computer related and going to acura as soon as they open.

 

So my local acura dealer won't look at my car being it's "too modified"

But I noticed I don't get misfires when it's cooler out side low to mid 70s. But when it is 80 or higher I start to get misfires and always get them when it's around 90.

I can't go to another acura until next weekend but could this be related to something other then the ecu?

Possibly iat sensor?


Thanks for the help people.

 

Have you confirmed that the ECU reflash has been completed?

 

They refused to check being my car is not stock.

I will be going to another dealer tomorrow. Hopefully they won't give me such a problem.

 

Just an update.

I have an appointment at acura for Monday.

The service rep told me he can't tell if the car has ever been updated
It's going to be $126 to check & an additional $$$ to update if it needs to be.


Is this the going price? Or am I being ripped off?

Thanks again for the help.

 

^you're being taken for a ride.

as stated, there is a TSB or Technical Service Bulletin.
an Acura Dealer will tell you if the TSB has been performed or not, by simply checking the vin number at their computer.

you dont need to pay a diagnostic fee for them just to check out the vin number

 

Just got back from acura.

They said the ECM was updated. And that the car is not actually misfiring but running too rich.

They can't do anything else being the car is not stock.

 

you keep saying its not stock...

umm, what the heck has been done to it?

 

Sorry I didn't realize I never said what was done
Dumb move on my part

I bought the car with a full exhaust system with no cats & a apexi neo afc.
The apexi (according the guy I bought it from) only reads the rpms and does no actual tunning.

Other than that the car is stock motor wise as far as I know.

 

First, remove the apexi tuner, I have a feeling that's what's causing your issues. That thing costs close to $500, no one is going to spend that kind of money on a fuel management system that only "reads the rpms." I feel like the previous owner was trying to be Dominic Toretto and started playing with buttons not knowing exactly what he was doing. If it's running too rich then there's obviously something wrong with the afr and it's too much of a coincidence that it just happens to have a fuel controller attached.

Remove that and place it directly in the garbage, or sell it to someone who knows what they're doing. From what I've read, there isn't much power to be made from tuning these cars (if you aren't boosted) so odds are it isn't really doing anything to help.

 

^off topic; pics of SRT please.

 

Please excuse the Instagram filter lol.

 

No shop wants to mess with removing it and I'm honestly not confident enough to remove it myself.


I'll just have to look around and find someone willing to take the challenge.


I have a wideband laying around. I'll install that and see what exactly is going on.


Thanks for the help. I'll be sure to keep everyone posted.

 

Does anyone know if an innovate lc-1 can be connected to the factory o2 sensor?

 

Well I think I found the problem. There is a comptech usa acm installed on the car.
I believe this is causing the issue

 

I'm not 100% certain but as I recall that component is used along with the Comptech SC right? (dumb question). After everything you've told us, it definitely sounds to me like the car was boosted at one point and the previous owner did a half assed job putting it back to stock-ish. At this point, I would recommend taking the car to a shop that does dyno tuning and either:

A) See if they will remove everything (tuning wise) that was installed.

or

B) See if they will tune it using the existing components to try and get everything back into spec.

Then again, I've never looked into tuning my TL so I'm kind of talking out my ass here and I'm sure someone will put me in my place shortly after posting this LOL.

 

You're 100% right.

I found the manual for the ct supercharger was able to disconnect it along with some rewiring. The car is running 100% now.

Also the apexi neo he had was only wired to the rpm signal. He had a $500 tach that did nothing for him.


I'm finally happy with the car lol


Thanks everyone for the help. This is the first car I purchased on my own. I'm only 21 and now know never big a modded car! You just never know what was done previously.

 

A buddy of mine had an issue like that with his WRX, the seller told him it was bone stock and after he purchased it we looked it over more closely and found that the radiator support had been clearanced to accept a massive FMIC, and one of the downpipe bolts that connects to the turbo was missing. Amongst other issues, it was obvious the car had been modded to shit at one point.

Glad to hear everything ended up working out though! Now go enjoy your new ride!