Tire pressure monitoring...
 

My car now has about 2500 miles on it and I get a warning when I start it up that my front right tire is low by -4. However, when I look at the reading for all four tires they show equal or a small variance by a pound or 2, but never by 4. They have always changed a little due to road surface, temperature, etc. My dad even took a guage and checked my tire pressures and added a little air. Nothing was down by 4 though. Still, when I start the car it gives me a warning that the front right is down by 4. It's always the same, front right, -4.

I called the service department and they said the sensor could be bad. Needless to say, I'm not too excited at the thought of taking a day off work and taking my 3-month old car in to be looked at. Has anyone had this problem or are familiar with it? I'm wondering if it's just something that got tripped that will reset itself after a bit.

Chances are the sensor in your wheel is faulty. I doubt it will just go away or reset. The sensor is connected to the valve stem, sits inside the wheel, and sends a signal to your TPM. It's about the size of a thumb drive for your computer. When you think about the harsh environment it lives in, it's kind of amazing it works so well.

So why not make an apointment and drop your baby off? This might be the first time strangers will be examining it, but probably not the last. They'll give you a loaner and the repair will be free. You paid good $$$ for you baby, why not have it in perfect condition? Just be sure to tell them to be careful with those gorgeous rims.

2500 mi in 3 mo? Not bad. I've got 6500 in 6 mo.

Shoot, that poor little sensor has probably melted in all this heat. I guess I'll take it in. They sure didn't mention anything about a loaner car when I called though.

Call again. It's part of the Certified Used Porsche program, I'm sure it's part of the new car warranty. If you don't ask for and reserve a loaner, they may be able to weasel out of it.
Tell them if they don't give you a loaner, you'll shove them in your frunk!! :rolleyes:

Well, I might have to shove the whole dealership in my frunk. I was told they don't have a loaner fleet.

Try adding a few pounds first. These things can be very touchy sometimes

My dad did add air and checked it with a gauge. The warning about the -4 pounds didn't change. Whenever I look at the computer monitoring for all four tires it varies, but the -4 never changes. Maybe if I bring it in they'll find there is nothing wrong, but it's just odd that every single time I start the car for the past few days it tells me I'm -4 on the front right. I wouldn't really care except for the fact that I'd hate to have a real problem and then not realize it because the monitor is faulty.

Ahh... the infamous Porsche of New Orleans. Don't get me started on them.

I think I'd contact your salesperson (if they're still there) and raise holy hell with him / her about buying a premium car and being treated like you own a Kia. Oops, I forgot we're talking PoNO and they probably don't care about fostering a long term relationship. Might also try the Service Mgr. Not having a loaner program sounds like a bunch of bunk to me. Isn't that dealership a sister to a Mecedes dealership? Bet their customers get loaners.

I feel for you LB. Can't imagine their service techs are going to be too good with the overall attitude of that dealership. What is PoNO going to be like when you have something serious go wrong?

Since the TP Monitor lives on the inside rim, before going to the Dealer, snap a quick pic of each of your wheels, along with a current daily newspaper (to show the condition of the wheels on a certain date), before taking it in.

If your wheels get scratched when they pull/mount the tire back on the rim, you have proof that it happened at the dealer and not from curb rsh or such.

Add ten psi over the recommended pressure on the problem tire. I believe you then have to drive 20km to calibrate the system, check the display to see if the pressure has changed.

So if my tire had been low and my dad added some pressure it would take 20 KM for the warning to reset? (and how many miles is that???) I'm sure I've probably driven that since though.

I never thought I should be worried about them scratching up my wheels. Oh, goodness. This is a pain in the butt.

I had a great experience with the salesman I bought the car from. Yes, Porsche of NO is right next to a Mercedes dealer, and I think they are both owned by Benson. My dad sells Mercedes parts and told me that the Mercedes dealer does not give loaners but has a rental place on premesis where you can rent a car. I don't know if that is true (he gets things confused sometimes) but if so, it really bites. When I had my Lexus I got a loaner. My mom brought her 1999 Volvo to the dealer and they gave her a ride home! She didn't even buy the car from them. So I want to know wtf is up with a dealer that can sell cars for 100K and up and not offer a person a loaner car???? It's no wonder they lose sales to Lexus.

I didn't buy my Boxster for the service department perks. I bought it because I liked the car. But you'd think something simple like a loaner car when your new vehicle with 2500 miles on it has a problem wouldn't be too much to ask. I don't even care what they'd loan me. But how can they expect people just to take off of work to sit in the dealership waiting for their car?

20km=12 miles.

I remember reading something about needing to have more then 32PSI in the tire and driving it to reset. I'll try and find the info and post back.

Thanks. I've definitely driven more than 12 miles but I dont think the pressure was up to 32 psi. I think the recommend front pressure is 27.

Sundry items:

27 seems low for 19s. Look at the tag in the door sill (just below the chrome hook for the latch) when you open the driver's door. It'll give you the proper pressure. I don't know if we have different tires since mine's an S and your's is a base, but mine is 32 and I have 19's. Maybe you are down 4#.

Benson must be playing with his Saints too much and lost track of time. This isn't the 80's. He needs to get with the program. However, I suppose he's the only Porsche and Merc dealership in the area, so he thinks he can set the rules. Woodhouse here in Omaha always gives a loaner if your car has warranty left. Too bad there wasn't another Porsche dealership in NO to provide a little competition.

Yes, service techs will need to be careful with your wheels. In today's photoshop world, it may be useless taking a picture of a newspaper next to your wheels. Might work to take a pic of the service mgr looking at your wheels, though.

I got the 27 psi from the door panel. I could be wrong about it being 27 though. My dad is actually the one who looked and put in the air. But if it's low then why would only one side show up -4? It's equal pressure on both sides. My backs are higher psi than the fronts.

Yep, this is the only Porsche dealer around here. And I don't think they sell a ton of them in New Orleans. They do sell quite a few Mercedes it seems though so I don't know what the deal is with the service. The girl I talked to on the phone didn't even give me a really complete answer. I kept asking if it's just locally, that that dealer doesn't give loaners but not all Porsche dealers, and she kept mentioning that they don't have a loaner fleet.

When I was in Tampa I took my Lexus in once and they were out of loaners. They rented me a car and had it brought over to the dealer. I didn't pay a dime for it, not even the gas in the tank. And my Lexus was out of warranty.

Okay. I just looked in the door frame with my own eyes and the front pressure is supposed to be 32, back 37. I don't know where my dad got 27 from, but I'm thinking maybe he needs to get his vision checked.

Take a reading on the left front and see if it's close to 32 (remember to do this in the morning before driving it, aka a "cold" reading). If it's 32, then mystery solved as to why only the right front sensor shows -4.

PS. Don't be upset with your Dad. He's just trying to help his favorite daughter. However, a word of advise. DON'T let your Dad add any fluids (antifreeze, pwr steering, oil, etc) to your car unless he's a Porsche guy. These cars take special fluids and adding ordinary fluids will damage your car. Most people don't know Porsches require special fluids, so unless he knows Porsches he may think it's OK to top off with what he has in the garage. That will be a costly mistake. Might want to casually mention this to him now before he tries to help you out without telling you. It will be too late then to have that conversation.

So the recommended pressures are for a cold tire, not one that is heated up? If so, then I think they are all low. Maybe I should take the pressures in the middle of the night because that's about the only time that it's not hot around here.

Ah, and thanks for the advice about adding fluids. I'd like to think that my dad would know what to do and not to do since he's been working with cars in one way or another for his whole life, but then he's the one that seems to have gotten the tire pressures wrong. I don't think he'd just add fluids to my car, at least I hope not. He seems like he's getting nuttier as he ages though.

When I was planning to buy my Boxster he kept griping and carrying on about how he didn't understand why anyone would get a Porsche and I shouldn't get one, blah, blah, blah. Then right before I was about to get it he sends me an e-mail with a whole bunch of info about Boxsters and tells me they look like great cars. Now that I have it he loves it.

That sucks they don't offer loaners.

I generally don't trust TPMS due to their general lack of accuracy. But it is good to know if a tire is going flat. On such nice wheels I would suggest investing in a good gauge and keeping an eye on them every now and then.

32psi sounds better for a 19".

Husker... I feel what you are saying. The dealer I bought my '05 from said they changed the oil, I believe them, but its a used chevy dealer. As competent as they are I have no idea what they used. I plan on changing the oil in 3K or less miles. Good fluids are important too.

P.S. how does the boxster deal with the rough NO roads. My 944 was not happy with the potholes and rough/unevenness. I bottomed out a number of times when I was there.

Good luck and I hope it all works out!!

NO roads are not the best for this car. That's probably why SUVs are a lot more popular here than sports cars. I have to be really careful to avoid potholes. I also got a tire/wheel warranty that covers just about anything except for me hitting a curb.

LB, I'm not referring to the outside temp in NO when I say take a cold reading. I mean take the reading before you drive your car for any distance. Just like an engine, the air in your tires will heat up when you drive your Box, which causes it to expand. Your pressure will then show a higher number if you measure it after driving the car (expanded air = higher psi).

As far as the fluids go, in most cases Porsches require synthetic oils (oil, pwr strg, etc). The antifreeze is typical European in that it doesn't contain phosphates but most of the popular brands sold in parts stores contain phosphates, so they won't work (even if you drain all the antifreeze and replace with phosphate a/f). In general, what your Dad may have in his garage probably won't be the proper fluid for your Porsche.

I took a reading and it's 33 front, 38 back. I think my dad told me the wrong thing when he told me 27. I didn't add any air just now, just checked the pressures, and now the TPS system is telling me that it's resetting or something so I'm going to go drive a bit and see if it resets itself.

LoveBunny,

The TPMS will show a -4 even if the tires have similar pressure if it over 4 psi below the recommended pressure. So as you figured out, 27 is below that level and you are getting the warning. It should reset itself rather quickly now that you added air.

I didn't add any air today though. I just checked the pressure and discovered that basically the 27 my dad told me was just him forgetting what it had been. The message I got that it was still acquiring the pressures has gone away and the stupid -4 warning came back on, so I guess I'll bring the dang car in tomorrow morning.

The dealer has informed me that I was supposed to have 36 in the front tires and 39 in the back. I'm not sure how I was supposed to know that since the door panel says 32 and 37, but apparently that was the problem. I haven't picked it up yet, but I'm sure they'll probably charge and arm and a leg to put some air in my tires.

Hey LB, my bet is that since those wheels (those are 997 Turbo wheels in 19") did not come on your car, the sticker in the drivers door jamb my be incorrect. I have 19" Carrera Classics and my sticker also says 32/37.

The sticker says 19" wheels, so I assumed that it was correct. Oh, well, at least now I know.

Luckily I didn't get charged to find all this out.

The explanation I got from the lady at the dealer is that the computer is set at 36/39 so that's what it has to be. This makes no sense to me. I don't understand why what a computer is set at determines what amount of pressure a manual guage should read on my tire. Maybe I just didn't understand her explanation. I was really tired and recovering from a migraine.

Built in tire sensors? Man, have we become lazy wimps... :)...whats next? self parking..jeez..

I still check my 4 tires manually.

I think this is becoming federally mandated soon, partially due to the Ford Explorer & Firestone tire blowout issues from a few years ago.

See, the problem is when I checked them manually they were correct, at least according to what is listed in my door panel. But apparently that's not the correct pressure according to the computer. It really is so confusing to me I wish I could just manually check my tires and not be bothered with it.

Yours is probably set higher because you have the 19" TT wheels which I assume are wider than 19" CC's and would require afew more PSI to keep the tires from riding on there sidewalls.. just enough so that center of the tire protrudes out more and edges make even contact with the road. When you have too little PSI the center of the tire tread will colapse slightly and the sidewalls will take the grunt of the vehicle weight against the pavement.

so maybe what is listed in my door panel is for 19" wheels but not for my specific 19" wheels? i know it does say 19" so that's why I thought it was what I would need.

I believe that is the case. You should be good now so long as you keep it at 36 psi.. did you notice it was easier to turn the steering wheel and the roads were slightly more bumpy since the increase in PSI?

I really haven't noticed much difference driving it, but the difference was maybe 3 psi.