2003 Trailblazer No Mass Air Flow Sensor, Then What Are These?

[@dustinsantorelli6554]

4 years later and helped me learn that isnt a maf but an air temp sensor. just ordered a new one. thanks!

[@EYVOAuto]

Thanks for watching! Glad it could help out

[@justinoff1]

I cleaned my throtlebody and it made a night and day difference

[@MikeBeatzcom]

"Shoutout to Nexus Auto for the amazing tutorial! Your step-by-step guide was exactly what I needed to fix my Trailblazer. Thanks to your video, I saved a few hundred bucks on repairs and did the job myself. Highly recommend! #DIYRepair #TrailblazerFix #MoneySaved"

[@crystalquinn6551]

Thank you . Was going crazy trying to find the mass air flow sensor

[@EYVOAuto]

Me too! Thanks for watching!

[@100thomasmagnum]

My 2003 GMC Envoy XL (basically a Chevy Trailblazer) would stall at stop signs and eventually stalled out resulting in requiring starting car up at stops. Cleaned the throttle body with throttle body cleaner and completely resolved issue.

[@EYVOAuto]

Awesome, that was the solution to my problem as well! Thanks!

[@gynell2043]

@@EYVOAuto I hope you're still replying to this video. I actually have a 03 GMC Envoy SLT with a 4.6l votec engine and it looks crazy identical under the hood as this one. So does this means that my SUV doesn't have a MAF senor as well?

[@laurenceprantner8618]

Ya, I have an '02 Olds Bravada, and it too is running around without a MAF sensor; this is a MAP sensor ONLY setup; good thing too. A new MAF sensor could cost up to 15 times as mush as a simple MAP sensor; on Amazon the MAF sensors for newer GM (Trailblazer, Bravada, Envoy, etc) are up to $150, whereas the MAP sensor for my vehicle is only $12. Thanks for the video!

[@EYVOAuto]

Thanks for the comment & for watching! There's a lot of confusion around this, not sure why GM didn't just use the same system for them all.

[@charliebrown92586]

I too have an 02 bravada and its setup is weird. Just like there is no egr valve. It has whats called a variable valve timing (vvt) solenoid. Strangest vehicle I've ever owned..but damn even 300k miles she still runs great when she runs good..lol

[@tammyfehse7274]

Thank you so much for this video!! Extremely helpful!! Now i can finally get my Envoy on the road!!

[@EYVOAuto]

Thanks!

[@gerarddugas6224]

You are right. The one I bought from Rockauto is going back. They said it would fit my 2005 Trailblazer I6 4.2 liter. Wrong.

[@EYVOAuto]

Thanks for watching! Very confusing... I never could really figure this out... Wish I could do more videos on this car!

[@garyheichel7336]

That motor is a 4.2. And yes it does have a mass air flow sensor text closest plug to the filter itself. And if you want your vehicle to perform properly after you clean a throttle body or do anything on that Chevy you need to disconnect the negative battery terminal so when you plug it back in the computer will tell you that you did a change to it no matter what it is

[@EYVOAuto]

Hi, great advice! I should have disconnected the negative terminal to reset the computer so it could have relearned how to run with a "new" configuration. As far as I can tell from research some I-6 4.2's had MAF's and some didn't. 100% correct the car shown in the video does not have a mass air flow sensor. They all have an air charge temperature sensors among others, but confusingly some were not yet produced with the MAF until later. A quick OBD scan or a Chilton repair manual will confirm this.

[@flyboy2610]

@@EYVOAuto Actually, when you clean the throttle body you don't want to remove the negative battery cable. Doing so will send the HVAC actuators into calibration mode when you hook it back up again, and you risk breaking the plastic gears in them. Instead, pull the fuses for the PCM, located in the fuse box under the hood. On my '04 TB and the wife's 06 TB they are fuses #10 and 28, PCM-B and PCM-1 respectively. This will allow the PCM to forget the compensation adjustments it's been making for an increasingly dirty throttle body, but won't send the HVAC actuators into calibration mode. You want to leave those fuses out for 30-45 minutes, so if you pull them when you start the throttle body cleaning job they should be ready to go back in when you're done. And when you're done, start the truck and let it do nothing but idle for 10 minutes, don't push the accelerator pedal at all. This lets the PCM relearn the throttle body settings. I did this to both our TB's and it worked flawlessly.

[@odasity2970]

@@flyboy2610 I've seen people saying different things, so if I pull the fuses I don't disconnect the Battery? I thought you were supposed to disconnect the battery then pull the fuses or am I mixed up?

[@flyboy2610]

@@odasity2970 You are correct. If you pull the fuses you don't need to disconnect the battery. Pulling the fuses will allow the PCM to 'forget' all the adjustments it's been making to compensate for an increasingly dirty throttle body. Leave them out for about a half hour while you clean the throttle body, then reinstall them and do the idle relearn procedure.

[@odasity2970]

@@flyboy2610 does the system do the idle relearn procedure itself after re installing the fuses or do I need to hook it up to a machine to have it done?

[@charliebrown92586]

I just needed to verify that i wasnt going crazy about that being the map and not a maf..just like no egr valve like i explained down before..and not many videos on bravadas. Have to watch a trailblazer or envoy video instead lol thanks for the explanations.

[@EYVOAuto]

Thanks for watching! Wish I could do more videos on this car!

[@micheleden345]

Great video I was wondering what was that sensor too.

[@allenboyden77]

I have a 2004 envoy with no mass air flow sensor. I'm a mechanic so i know where thing's are or normally are but this one doesn't have one and I've went as far as going through wiring system to make sure hasn't been eliminated. Nothing so guess it is what it is not sure why some have them some don't but this model is an xuv so assuming maybe that's why maybe where it was built for north or south. I worked in a factory for 20 years and it definitely makes a difference how the part is rust proofed or whatever depending on where its going in the country up north everything got a better grade of paint but its more or less a better grade rustproof coating. I've never seen a gmc after early 2000s without mass airflow sensor. So been trying to make sense of it. Specially since costumer is having symptoms that mass air flow sensor causes lol

[@brewcitymike1]

DO NOT use carb/choke cleaner on the throttle body. You need to use a TB cleaner that specifically says "safe for sensors" or you can ruin your sensors as well as erode the coating on the throttle plate.

[@EYVOAuto]

Thanks for watching! 2nd this, carb and choke / brake cleaners are a lot stronger than throttle body cleaner. I might have done it in the video, but there's no reason to chance it!

[@garyheichel7336]

I may suggest if you have a Chilton repair manual it will show you illustrations of where all your sensors and vacuum and everything is. I work on all types of vehicles periodically I even have a 07 Trailblazer that I maintain

[@EYVOAuto]

Chilton repair manuals are the best! The 07 will have a MAF but this 03 4200 engine does not from the factory.

[@ProjectCarTV]

Intake Air Temperature Sensor

[@EYVOAuto]

Thanks!

[@harlensmith3023]

I believe you might need a o2 sensor. There's a up stream and down stream

[@CarlosGuerrero-pf2iy]

Will they supposed to have a power that wire

[@samuelrobinsoniii2037]

Thanks I appreciate you.

[@EYVOAuto]

I appreciate you! Thanks for watching!

[@fernesal]

Eyvo auto. I have a question for you. Where can I find the pcv valve for that kind of truck? Mine it is also a 2005 6 cylinders inline 4.2 2wD. According to this one on your video there are some differences in the air resonator. Mine doesn't have the vacuum line inserted on the right side of it. Only underneath of it. But I can't find no pcv valve.

[@EYVOAuto]

It should be located on the driver's side valve cover towards the back or the firewall. From what I read on line on a few different forums it should be a pretty easy fix, but you may need to remove the air box to get to it. This site had the best instructions I found: itstillruns.com/replace-pcv-2005-trailblazer-6613460.html

[@hamadaawad9417]

Good day from Egypt Pls. why RMP not increase than 3000?

[@shalomhamachiah1494]

My engine icon is on and I don't know which sensor to replace. This is a 2003 Chevrolet Triblazer. Would you help me? Thanks.

[@EYVOAuto]

Oh no! A good place to start would be to get the code scanned with either an OBD Scanner yourself or to go O'Reilly's, Advanced Auto Parts, or a shop and have them read it. There could literally be a 1,000 reasons why a check engine light comes on. Once you've read the code, I then search the car and the code to see any common fixes or problems that cause it. That, along with any physical symptoms, will give you a more narrowed down place to start diagnosing what it could really be if you're going to try fixing it yourself. Hope this helps!

[@arifelassal2874]

The box connected to the throttle body is called the silencer

[@EYVOAuto]

Thanks!

[@CarlosGuerrero-pf2iy]

I tested that wiring they don't have no power my envoy 03 4.2

[@amartinez2071]

2006 has a MAF but doesn't that IAT.

[@EYVOAuto]

I'm not entirely sure when they added it, but weird the 03 doesn't have one & is still considered a modern engine...

[@nanjemoyal-kursi3078]

4.2 liter straight line 6cyl and the mas airflow sensor is on the passenger side.

[@IsshmanGarcia]

There is NO Mass Airflow Sensor on this truck. It is a speed density engine which has a MAP and IAT sensor...NO MAF!

[@nanjemoyal-kursi3078]

@@IsshmanGarcia * I meant to say map. Thanks

[@cordwoodenties5505]

are you sure this truck doesn’t have a MAF? i have a 03 chevy blazer and it is giving a bad MAF code

[@Barbaratio]

@@cordwoodenties5505 so I've seen some of these trucks that have them, and some don't. As well as some trucks that have a sais system and others that are just plugged off.

[@notchagrandpa8875]

@@cordwoodenties5505 the 4.2 trailblazer has a MAP sensor he covered it in the video it also has an intake air temperature sensor also covered in the video, and some have a SAIS while not commonly found on 02 or 03 models

[@trevorjohns2909]

I need help with my trail blazer Please look me up on face book messenger

[@EYVOAuto]

Hi! Hopefully I could help! Don't have a ton of experience with that car. DM me on Instagram EYVO_Auto

[@davidames5317]

This was the most uninformative video i have ever seen. You literally talked just to hear your own voice and accomplished nothing at all except pissing me off and wasting my time. Next you make a video do what you say you are going to do.