patrickt

Here is some good infomation I have come across for you all. This was discovered by them while testing thier intake for the 5th generation Camaros and hence the same issue has been reported on several Corvettes with either the LS3, LS7 or LS9, mainly after the install of a intake because of the increased airflow. There have been reports from serveral people of hesitations without a intake install and this has been known to fix those cars as well. I have these available if you check and find you have a "weak" one. They are all double verified once when new stock is recieved then again once it is shiped.

This was from Vararams web site.

The Air Meter


During our testing we discovered a disparity between identical Camaros in terms of there reaction to changes in airflow and weather conditions.

We noticed that one car would be finicky at cold start and the MAF would scale "weak" while others would be strong and clean.

What we discovered was that the 'WEAK" meters were reading 1560-1670HZ at idle with the A/C off (OEM is 1800MHZ+)
During on road, light throttle input the MHZ would be slow and weak to respond to throttle changes (hesitation)
Wide open throttle showed 120-170MHZ lower than OEM stock (OEM is about 8600MHZ) on the same car.

Weak Meter Fuel trims-
The fuel trims would go to -15% using a VR -3% for a panel filter and -5-8% for other intakes. MHZ would drop as would the idle. When the MAF scaled in at WOT each would richen up accordingly.

Test 2 we pulled the filter from the VR completely, this resulted in fuel trims dropping down from -15% to -24%, MHZ dropped another 70-90MHZ. The car would drive fine but WOT operation was basically weak/flat and timing was low etc...
Now with one simple meter swap which takes about 1min the car immediately corrected, went back to 0% fuel trim MHZ jumped back to 1800+ all within 30 seconds! The car drove like a Rocket!

We began final confirmation by swapping air meters in cars and doing volt meter testing in static conditions. 30 meters, 3 cars = the same exact result every time. We confirmed this with VR customers tuners around the US.

The Result is that these 'weak" meters are not showing the same resistance levels as the majority of OEM meters.

This lead us to contact the GM rep and the actual manufacturer of the meters (its not Dephi) They confirmed the factory which allow us to identify each meter.

These numbers and letters are located on the back of the meter as shown.

(WHAT TO LOOK FOR) The factory code.




The suspect meters have all consistantly had a single letter located in this area VS a number with a letter.

Here is the catch 22

If the airflow is not changed by a substantial amount (our flow testing verifies that most of the aftermarket boxes do not) over OEM then the meter will be within OEM Tolerance but will always be "weak"
you cannot tune this out, its a fundamental issue with the resistance of the meter. It needs to be replaced. This is why some cars are finiky and some are not.

Don 79 TA

this would not apply to a 2005 LS2?
what would be different?

Redvette_22

If the meter has one digit, is it a warranty issue ? Is this possibly the issue with A6 trans shift delay issues?

el es tu

GREAT info!

B-Vette

Another example of what makes this forum so great - thanks for the write up!

Justasheet

dgrant3830

So for clarification purposes, Patrickt you are saying that a MAF with a single letter designation is a possible bad sensor and sensors with the letter and number combination/designations are good ones? As someone else asked, does this apply to LS2's as well?

JoesC5

This info was published on this forum quite awhile back. From that time to now, I haven't seen any posts where people actually changed out their "single digit" MAF's to the "double digit" MAF's.

Has anyone actually checked their MAF and confirmed that the "single digit" MAF was causing problems and did they find that installing a "double digit" MAF solved the problem?

73sbvert

Streetk14

The LS2s use a totally different type of air mass meter. So no, it would not apply to them.

AirBusPilot

I just pulled my maf. It doesn't have a single letter, but a single NUMBER (3).

Are single numbers causing problems too?

Delbert

Very informative post

I just had my MAF out today and didn't check this info. I have noticed recently when I start my car after it has been sitting for 24 to 36 hours that it loads up for about 10 seconds. Sounds like I have a real hot cam.......then it smooths out and drops from about 1100 RPM to the normal 600 RPM. Haven't noticed any other issues though.

I'll have to pull it out again tomorrow and have a peek!

spdmn75

06Z may build date I had a P coded one

Ragtop 99

patrickt

the LS2 does not apply since it uses a different maf

patrickt

Most likely it is not a warranty issue because the findings show the problem mainly with an aftermarket airbox. If you dont have one it would be if the dealer narrows it down to it and it could cause a shift delay

patrickt

your quite welcome hopes it helps alot of you with a ghost hesitation with not light or codes

patrickt

This does not apply to LS's but yes you are correct a single letter designates a possible weak sensor. Now if you are not having a problem then you are fine but if you are then this may be the solution

patrickt

single digit ones are good its just if it is a letter only that it is a possible problem

patrickt

I have not heard of an issue with them but this is also the first sensor I have heard of with just a number. Most are either a t letter solo or a letter and number. Since I didnt do the testing I honestly dont have an answer for you