So I have an 04 GT that I brought in on Friday because the service engine soon light was on. So I go there and just have them do the 30,000 mile service as well. So they call me up on Saturday and tell me the car is ready. I go to get it and the damn service engine light is still on. So I leave it again and they call me today and tell me that since I have an aftermarket TB that it's causing my #2 cylinder to misfire and for $450 they will put a stock TB on for me. So I'm thinking...how the hell would that cause a cylinder to misfire?!?! Is there something that I don't know about or what?? Please help. The TB I have on now is a Accufab 70mm with plennum. Ohh...and they charged me another $100 just to hook it up to get troubleshooted. A$$holes.

just for future reference you can go to autozone and they will tell you what it is for free. I don't see the misfire, but it could have been a bad air/fuel mixture. I hadmy CELgo on for that before, that's all it said bad air/fuel mixture.

FORD's full of shiiiiiiiiiiit

Do you have a tuner of any kind?

ORIGINAL: mustang_marine8762

So I have an 04 GT that I brought in on Friday because the service engine soon light was on. So I go there and just have them do the 30,000 mile service as well. So they call me up on Saturday and tell me the car is ready. I go to get it and the damn service engine light is still on. So I leave it again and they call me today and tell me that since I have an aftermarket TB that it's causing my #2 cylinder to misfire and for $450 they will put a stock TB on for me. So I'm thinking...how the hell would that cause a cylinder to misfire?!?! Is there something that I don't know about or what?? Please help. The TB I have on now is a Accufab 70mm with plennum. Ohh...and they charged me another $100 just to hook it up to get troubleshooted. A$$holes.


I'm sure they will! Hell, i'd put your stock one back on for that kind of money. Those MF'ers at that dealership have lost their damn mind.

Ok...I didn't think that could happen either. I sounded kinda fishy. I've had the TB on there for about a year now and the light just came on last week. The motor doesn't sound like it's running funny or feel different in any way. And no...I don't have any tune or chip for it yet. I'll look into that air/fuel mixture theory though. Thanks guys.

You need to find out what code(s) are being thrown... There's no way that the Accufab TB & plenum could possobly cause a misfire on cylinder #2--only...

The code that they had on the sheet was P0172. So whatever that is, I have no idea. It says on the sheet:

IDS test code P0172, pinpoint test, needs factory TB.

http://www.obd-codes.com/p0172

Looks like you're running rich

Thanks for the info on that site. I'll get it check out and see what the outcome is. Thanks again.

Never take it to a dealership. Learn to do it yourself or sell it and buy a Camry.

I'd go to AutoZone and ask them to use their OBDII sensor and they can tell you the problem and print it out with the problem, causes, and solutions...I had my cylinder 4 misfiring and all it was was a bad gap on my spark plug...I'd check that first, it was easy to find my #4 cuz my wires are numbered...I could tell you which one #2 is if you need it...

Oh and codes are different for every car, and according to that website there's not even a match to that code for Ford...

Here are the possible causes for P0172 (http://www.paladinmicro.com/PalMFrame00.htm?wks=obd&dtc=P0172), from the factory shop manual--nothing to do with the TB...[/align][/align]Take a look at the MAF sensor, make sure it's plugged in correctly--if so take it off and look for physical damage.[/align][/align][/align]

Thanks for all the help guys. I knew I could count on MF.

yeah....i wouldnt take it to them..id get it checked out first before you commit to anything.

Yea...I'm deffinetly not taking to them again for anything like that. Now that I know Auto Zone will do it for free.

But don't get confused cuz they won't fix it or anything, they will just read the code for you, and unless you get a good person up there or you are knowledgable enough yourself, then they may still not be able to help you...So make sure that you have them read the code and then print it out for you so that you can take it to your mechanic....

the longer you have your mustang the more you will realize that you need to learn to fix it yourself. small things go wrong frequently and unless you canfix them yourself, ford will continue to give it to you up the ass.

EDIT: btw...be sure to check the price on parts. theyve tried to overcharge me for parts multiple times and everytime ive complained theyve said, "Well actually we can cut you a 'deal' and sell it to you for $--." a$$holes.

ORIGINAL: 945LSTANG

the longer you have your mustang the more you will realize that you need to learn to fix it yourself. small things go wrong frequently and unless you canfix them yourself, ford will continue to give it to you up the ass.

EDIT: btw...be sure to check the price on parts. theyve tried to overcharge me for parts multiple times and everytime ive complained theyve said, "Well actually we can cut you a 'deal' and sell it to you for $--." a$$holes.


I agree with this statement 100%. I have never went to the dealer for anything non warranty related except to reflash my computer for PATS. I'd rather spend my money elsewhere than waste it on them.

P0172 (System too Rich Bank 1) could be your O2 sensor.

ORIGINAL: mustangman03

P0172 (System too Rich Bank 1) could be your O2 sensor.


Exactly. Go to AutoZone and get an 02 Sensor($40-50). Replace it(it takes all of 10 mins) and then go back and tell them to clear all the CEL's.

If that doesn't work, go get a set of NGK TR-55 plugs(~$15) and gap them at .045. If your plugs are fairly new, then just replace #2, but make sure the gap isnt too large.

yea first thing id check was 02 sensor

I found this in a old book i had, not sure if it will help you or not.


The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters (K&N, etc.) can cause the MAF to become dirty if the filter is over-oiled
There could be a vacuum leak.
There could be a fuel pressure or delivery problem [/ol]
Possible solutions include:


Inspect all vacuum and PCV hoses, replace if necessary
Clean the MAF sensor. Consult a service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
Inspect fuel lines for cracks, leaks, or pinches
Check the fuel pressure at the fuel rail
Check the fuel injectors, they may be dirty. Use fuel injector cleaner or get them professionally cleaned/replaced.
Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible) [/ol]