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BigDaddySRT
04-05-2013, 08:02 AM
I'd seen lots of concerned post of people saying their Tires aren't inflated properly from the Factory.

After putting 500 miles on my ABARTH... I checked the COLD tires this morning before I left the House.

EVIC Readings (COLD):
RF 40.9 psi
LF 40.7 psi
RR 36.8 psi
LR 35.9 psi

So... due to the discrepancy I fired up the Compressor and grabbed my trusty tire gauge.

I checked the Tire Pressures Manually (COLD):
RF 35.0 psi
LF 35.0 psi
RR 35.0 psi
LR 35.0 psi


So... I turned the Compressor OFF and went about my merry way.

I'll bring up the issue when I get to my first Service Appointment.

Robert Nixon
04-05-2013, 09:38 AM
they're supposed to be different from front and rear, are you just saying your manual gauge read the same even though EVIC read different pressures?

BigDaddySRT
04-05-2013, 09:41 AM
they're supposed to be different from front and rear, are you just saying your manual gauge read the same even though EVIC read different pressures?

Yes... The EVIC Readings were completely different from the actual Manual Gauge.

Macchina Divertente
04-05-2013, 09:43 AM
I'm not sure TPMS sensors are all that accurate to begin with.
There was always a discrepancy in pressure readings with the Saturn VUE we owned between what 2 tire gauges would read, and what the TPMS sensors would say when I would get the monthly OnStar report.
I go by what my gauges say, not the TPMS.

2Cool
04-05-2013, 10:01 AM
I see about a 2-3psi difference on manual gauge vs the EVIC. First time I checked I thought my gauge was off, but two others I had read identical. So I go by the old school method instead. At 36psi front and 32 rear, likely need to bump to 38 front as Fiat recommends.

b56.1m6
04-05-2013, 10:15 AM
My TPMS sensors read 40.1 with gauge reading of 38 for the fronts and 33.3 with a guage reading of 32 for the rears. I was going to start a thread about this myself but decided to trust my gauge. I found my other two vehicles had closer readings on the TPMS with only one wheel that was off by 1 psi so I am thinking the Fiat system is not that accurate.

mkawa
04-05-2013, 10:47 AM
the TREAD act requires a TPMS to be installed in all vehicles sold new on or after 2008 with exactly the following requirement:

1) during a TPMS system malfunction AND/OR when one or more tires is underinflated by 25% or more, a "bulb check" must illuminate on the dash

that's it. it says nothing about the accuracy or behavior of the system in any other situation, and further, the nhtsa does no standardized testing to make sure that either OEM or aftermarket TPMS even fulfill this relatively simple requirement. the whole thing is kind of silly.

Guest
04-05-2013, 11:47 AM
I'd seen lots of concerned post of people saying their Tires aren't inflated properly from the Factory.

After putting 500 miles on my ABARTH... I checked the COLD tires this morning before I left the House.

EVIC Readings (COLD):

RF 40.9 psi
LF 40.7 psi
RR 36.8 psi
LR 35.9 psi

So... due to the discrepancy I fired up the Compressor and grabbed my trusty tire gauge.

I checked the Tire Pressures Manually (COLD):
RF 35.0 psi
LF 35.0 psi
RR 35.0 psi
LR 35.0 psi


So... I turned the Compressor OFF and went about my merry way.

I'll bring up the issue when I get to my first Service Appointment.

Check those pressures, recommended is 38F and 32R is it not ?

BigDaddySRT
04-05-2013, 11:55 AM
Check those pressures, recommended is 38F and 32R is it not ?

I'll correct them this afternoon when I get home from the Office.

I'll complain to FIAT about the EVIC readings being screwy.

mkawa
04-05-2013, 12:09 PM
your time and money are probably better spent getting a high quality bourdon tube based gauge (longacre vends great ones) and measuring the pressures by hand every so often. i typically keep a cheap gauge from napa in the car (usually one that measures relative to an atmo chamber, which may or may not leak :P), and then every once in a while i bring out a gauge that doesn't rattle around all the time and get more precise readings (ie, before events or other merry jaunts or whenever things feel a bit "off").

for a while i was running by the local gas station to fill up, but i've found the 12v compressor that comes in this kit to be particularly awesome: http://www.amazon.com/Slime-70004-Power-Spair-Repair/dp/B000YMP1SA/ref=sr_1_12?ie=UTF8&qid=1365178117&sr=8-12&keywords=tire+slime

it runs cool, quiet, is quick and has a long cord.

Guest
04-05-2013, 01:54 PM
The compressor that comes with the Abarth is pretty good and its gauge only shows 1-2psi out from my hand gauge!

BigDaddySRT
04-05-2013, 03:10 PM
your time and money are probably better spent getting a high quality bourdon tube based gauge (longacre vends great ones) and measuring the pressures by hand every so often. i typically keep a cheap gauge from napa in the car (usually one that measures relative to an atmo chamber, which may or may not leak :P), and then every once in a while i bring out a gauge that doesn't rattle around all the time and get more precise readings (ie, before events or other merry jaunts or whenever things feel a bit "off").

for a while i was running by the local gas station to fill up, but i've found the 12v compressor that comes in this kit to be particularly awesome: http://www.amazon.com/Slime-70004-Power-Spair-Repair/dp/B000YMP1SA/ref=sr_1_12?ie=UTF8&qid=1365178117&sr=8-12&keywords=tire+slime

it runs cool, quiet, is quick and has a long cord.

The whole idea of my post was the fact that the Factory TPMS Sensors are telling me through the EVIC Incorrect Tire Pressures.

So... Don't just trust the EVIC and go amongst your merry way.


The next time I have the ABARTH in for Service I will bring FIATs attention to my concern.

OhioMade
04-09-2013, 10:16 PM
After reading your post I checked the pressures with my handheld gauge. 42PSI all the way around! So I let the air out accordingly. When I check the EVIC they were within 1PSI of my handheld gauge. Thanks for the post--I thought the dealer would have set the correct pressure when I bought it last week. Noticably nicer ride now too.

Deefourtay
06-06-2013, 01:58 PM
I returned one of my tire gauges because I thought it was reading inaccurately & not matching the car's electronic one. Turns out the new tire gauge I bought doesn't match the car either, I guess the traditional method is the best!

shagghie
06-06-2013, 02:03 PM
The compressor that comes with the Abarth is pretty good and its gauge only shows 1-2psi out from my hand gauge!

Just double checked this myself yesterday. The Abarth's compressor ran exactly 2 psi lower than my high quality tire pressure gauge, so just add one 'notch' to your target pressures and you can feel reasonably well about it when measuring at cold temps. I didn't check against the EVIC TPMS yet though, but the last time I did, the right rear's TPMS sensor was not anywhere near the manual gauge. :-(

Dr. FIAT
06-06-2013, 09:58 PM
My EVIC pressures have been spot on with the numbers obtained using a manual gauge since I bought the car- 4200 miles so far. But I always default to my manual gauge.

DuckDodgers
06-07-2013, 11:59 PM
Just checked mine, and confirmed my TPMS readings are exactly spot on with my gauge. I've got a rubber coated, braided stainless hose BMW gauge that I've used for years. Paid $60+ for it over 10 years ago and it's still rock solid and accurate. I bought that particular model on the recommendation of an expert.

Todays digital gauges are pretty good, but an old analog gauge with the reading held until you release it is hard to beat...if it's a quality product!