backafter20

I'm sure this has been covered ad nauseum, but I did try several searches with no luck, so please don't flame me. My question is how a custom tune affects the engine warranty. My dealership says that ANY modifications to the computer will void the warranty immediately. I was told that even though you put back a stock tune when you bring it in, they can tell on the computer's log exactly what and when any modifications have been done. They say that you simply cannot make changes to the computer that they won't know about. Then today at a car show I spoke to a guy who works for a Lincoln/Mercury dealer who told me that the computer may keep a log, but your average dealer mechanic cannot access the information. The computer would have to be sent in somewhere else to access such a log, if it does exist. Now, is my dealer blowing smoke? I am very concerned about keeping the warranty intact, but I need a CAI to make my RKSport hood functional. I'd love to get a tuner, but not at the expense of my warranty. Thanks!

Shifty

Just make sure you put on the factory tune when you bring it in for warranty work. Unless you blew a piston through your hood they aren't going to go really deep into the computer.

tech

I ran this same question by my dad. He was an engineer for Ford for 30 years and he said unless they are doing a tune on the car or there is some sort of engine malfuncition they won't be tapping into the ECM and looking at the program. Granted, I know he did not work for a dealer, but part of his job was making warranty costs as low as possible, hence designing a better product.

I'm not trying to sound like a know-it-all, this is just what I heard and it seems to be a logical response.

Jewls05GT

I took mine in to the dealer with all of my mods and the tune, and they said absolutely nothing to me about it, just begged for all A's on the service survey.

scrming

Dealer is trying to scare you... find a new dealer... Today was a perfect example of what a good dealership is like...

I put in a Zex Nitrous kit... I've been getting a wrench/CEL on and off for a couple of weeks... I've done everything possible to figure it out... basically it seems that I have a bad Throttle Position Sensor, for which there is a TSB. So I went in to the dealership, showed them the TSB, said my car is getting the codes as described in the TSB. Service rep opens the hood... There is my Zex Nitrous kit, all hooked up, including the Zex wire that connects right to the TPS! Service rep comments on my helmet in the back seat... and on top of that the numbers are still on the windows from the track this last weekend! Tech comes out, pulls the car in bay... 15 minutes later he comes out and says "Parts will be here tomorrow...." Oh, and I didn't reflash my computer back to stock...

Unless the dealer can prove that your mod caused the problem they can't void the warranty... I mean one look at my car and it's obvious this car is no where near stock... LOL! Heck they could have easily said the Zex unit fried the TPS...

I'm not 100% sure... i didn't think they could tell if you reflashed your computer... but someone did tell me once that they could but 99% of the dealerships don't have the equipment or talent to do it...

Shifty

They will most certainly try though.

Sonic Brew

Technically they can't, but if they refuse you would to battle it out in court. And I think FoMoCo has a little bit more money.

scrming

I agree.. but.. a lot of people would have you believe that a mod will void the entire warranty... Dealership can't void the warranty on my power windows because of my Nitrous kit... that's what a lot of people don't seem to understand... at least that's been my observation...

GhostGT

Very true. But the tiny risk of something actually going WRONG with a part of the car you modded just scares me. That is the only thing holding me back from getting a tune. and my dad.

don_w

If you want to play, be prepared to pay... simple as that. Frankly, I don't give a rat's azz about whether the dealer will do warranty repairs for me or not. That's probably the last people I want working on my car anyway. If one of my mods breaks something, not only will I get it fixed, I'll make it better than it was. My 2 cents...

joesmustang

Which TSB is for the TPS? What's the symptoms?

scrming

I agree... I don't understand the logic "I'm not going to mod until my warranty is up"..... What??? Do people think it's cheaper to get something fixed AFTER the warranty is up? No disrepect here but... people that get so up tight about the warranty... Do they stop driving their car when the warranty is up?

scrming

I believe it's 05-15-04. You get a wrench light and sometimes a CEL too. You get a couple of P codes indicating a TPS error. It is for cars built befrore something like 11/05/04.

AFChief

You could get a CAI that doesn't require a flash if you are that concerned. I think I'm going with the BBK kit and Throttle body. Bolt-on, no-flash.

Of course I actually need a Mustang first.........

scrming

ok... here is my take and my experience.. While a company may say there CAI doesn't require the car to be re-flashed, does that really mean it's safe? Example I bought the MMR intake. No flash required. Noticable improvement in the higher RPM range. Start looking a the data coming out of the car. Basically the MMR intake was fooling the car's computer into thinking it was flowing LESS air than it really was (i've got the before and after data to prove it)... As a result the car was actually running LEAN (because it was getting more air than it thought it was getting) which is why it picked up some HP without a reflash.. hmmmm.... They don't tell you that part... I would say if you are going to put a CAI on make sure you tune for it... I certainly don't want to lean my car way out... (i think we had to do something like an 18% bump in fuel to compensate)