So I wanted to give a shout out to Dennis Rindlisbach and Joshua Pruden who, in Part 1- BEFORE I released Part 2, correctly made the call WITHOUT GUESSING and they each gave their data and calculations on exactly how they knew the issue.

See folks, this is the difference between someone doing something that they love vs. someone who does something because it's another paycheck. When you have professional repair shops coming to your home garage, you're obviously doing something right. Congratulations on all you accomplished so far Matt!!

Many years ago, an older mechanic told me, “A new part doesn’t mean it’s a good part.” Great job with this.

In the past, I didn't mind using aftermarket sensors, but here lately most of them have been a bust. Seems like in the last few years aftermarket has gotten worse.

Single female here. I just joined your pay site because I want to know what I need to know to diagnose my car issues. I'm currently having stall issues with codes po171 and p2096. I'm loving the thought of being able to find the problem through your tutorials help.

Rule #1 - when customer says "I've replaced all the sensors" first thing you do is go back and remove all the Chinese junk they installed.. people always buy the cheapest garbage they can find online

I too was a victim of my own parts cannon. One of the parts I replaced on my '99 Ford Ranger was an aftermarket MAF. My mechanic found it to be of the wrong voltage. He replaced it with a Ford part. Problem fixed.

From the first video , "every part changed" . I said to myself "I hope he kept all the original parts because I bet you all the new parts are cheap Chinese parts".

If I was a Judge, and you were in my courtroom facing sentencing. I would sentence you to six months of community service replacing air filters all day long ! 😆

Have exact same engine and been fighting lean codes for long time now. Replaced fuelpump, regulator, injectors, o2 sensors and every vacuum hose. Previous owner replaced MAF and it's an after market unknown brand. I have ordered an original maf-sensor. Many thanks for this information! Good work!

Matt, opening the air box or even not having it sealed completely bypasses the air filter (which has pressure drop). This will change flow though the MAF sensor completely (introduces air turbulence as well), so air measured through the MAF can change dramatically. Hence the dramatic changes in fuel trims at idle when opening or closing the air box. They are very sensitive to flow and location in the air box. OEM is best for these type sensors (knock sensors are another example where aftermarket replacements can have very significant negative effects).

I highly appreciate the self correction and awareness around the 29 minute mark when you discuss why you ‘just know’ that vacuum isn’t a problem, and then go back to elaborate on it.

I'm hooked, I love it. 27 years Jaguar tech but so many good reminders. You're doing exactly what we need. I guarantee no one remembers the basics and it's great to hear thought turned into word

Excellent work, Matt! This was one hell of an issue to diagnose, and it's very refreshing to see you question new parts! "It's been replaced" does not mean the same thing as "it works as it should", and it's very easy to forget that. This was a thriller to watch!

As soon as you showed how vastly different the MAFs were, I was already shaking my head.

Like this analytical approach, and this guy don't ramble on like some do about things completely not about the topic.this is a automotive chanel not a comedy chanel if you get the drift,it's OK to have some comedy but not half the video, I respect him for this and his approach.

Thanks for taking us along on this . As always , there is a risk of throwing parts at a problem . Especially if one is bad , a joker is now in the deck . Beware of " white box , no name , one size fits all parts " . On general principle , I tell friends with a drivability issue : clean the throttle body , MAF and IAC = just good maintenance . Most times they were never done . And a visual inspection BEFORE anything else .

This video saved me! Been fighting lean codes for a while ( I assumed it was vacuum leak) turned out it was and aftermarket MAF! I am so glad I stumbled across this video, my old fishing boat hauler seems to be better! Thank you for putting this out there!

That was great Matt! It really enforces the need for proper diagnosis before launching the parts cannon 👍 Well done you! 🤗

I love your content. I have learned so much about diagnostics from watching your videos. Thank you for what you do