Justaman

My car is a base model 07 Lexus is 250. I have owned it for about a month now. Saturday my cheek engine & VSC light came on. Took it to two different auto zones. there scan tools read a p0172, p0175 code. I cleaned the throttle body, and replaced the air filter but the check engine & VSC light remained on.
Next: I cleaned the mass air flow sensor but the check engine & VSC light remained on.
Next: I replaced the mass air flow sensor with a new one but the check engine &VSC light remained on.
Next: I replaced the old MAF sensor to return the new MAF sensor to autozone thinking I eliminated the possibility of having a bad MAF sensor. That's when I realized that I had left 2 hoses unconnected during this complete process after refitting the cleaned throttle body.
Next: I made sure everything was connected, took car to autozone, rescanned car and had a total of 32 codes! Most of them was repeating codes that I assume was coming from the 2 hoses not being connected. Below are pictures of the codes.
Should I 1: clear the codes to see if the throttle body cleaning was a fix?
2: disconnect the battery for one hour, reconnect the battery and see if codes come back? 3: spend the $100. Bucks for the dealership to scan the car

Justaman

Update... It's been suggested to me that I drive it for 50 plus miles on the highway with out stopping. Turn it of for 30 minutes before restarting it. Going to try this this afternoon after work. Hopefully this will at least get me back to my original starting point. Fixing a p0172 p0175 code.

Pittsy

If you bought a new MAF sensor, leave it in. Cant hurt to have it in there. Make sure everything is tidied up and the hoses are where theyre supposed to be. Unplug battery for 15 mins, then plug it back in. when you start the engine, itll die immediately, then restart it. You shouldnt have any codes.

Justaman

Hello Pittsy, thank you for responding and reading my long post I have the factory alarm system and was told that disconnecting the battery would cause issues acosheated with the security system like ( not being able to start the car). Is there any truth to this?

tarm

if you could not start the car just disconnecting the battery that would mean you could never start the car if your battery went dead and you jump started it or if you ever needed a new battery etc. Cars do have disable codes built into the ECM systems to prevent people from using electronics to bypass the security. Fords PATS system have this. Can be a PITA when you are doing tunes etc. If that gets tripped it usually can mean a trip to the dealer to get the disable code turned off.

Its almost certain all the codes you had are from the improper install that you corrected. But I do agree Pittsy that you should have kept the new MAF as its extremely rare to be able to just clean sensors that trip a CEL and have them work reliably going forward but I am not privy to the effects on these specific vehicles just sensors in general..

I would clear all the codes. Drive it for a day or two and recheck for codes..

I will also state something that I am sure a number of people will debate. I will qualify my statement with I have about 30 yrs experience in working on my and others autos diesels and gas alike. With that said I am far from a professional certified mech or an expert on any specific system. Just what I have learned thru experience and from a number of real experts in their field. When you buy sensors if you do not want a headache buy the stupidly overpriced OEM ones. Yes you take a beating on price. Online you can save a great deal but they are still more than the generic ones from the local china mart auto part store. Here s why. OEM are made to specific tolerances so unless you know the exact manf and the part number for aftermarket that is that same part the normal ones you get from auto parts stores have much wider/differing tolerances/specs.

How this turns into a nightmare is thru human deductive reasoning and improper placement of trust. When you have a issue and the first suspect is a sensor what do you do? You go and replace that sensor. Now what if the problem continues or after a short time it comes back say a few days to a week. You know you have a new sensor and you trust that sensor must be good as its brand new. So basic deduction tells you that it must be something else. Down the rabbit hole you go. Replacing parts etc. Yet its extremely possible that those cheap sensors were faulty or are not reliably in your specific engine /car. To this last point, I have seen a sensor not work right in one car and swap it to another car same make model yr and it works fine. Yet the OEM sensor works perfectly in that other car and this one too. Cars engines etc tolerances between sensor and pickups vary and more so as they age and wear.

A prime example of this is the famously long lived Jeep 4.0L straight 6. These things for being American will go 1/2 million miles if you just do reg maintenance on them. With a vfvle job they can go 1 million miles. These things are awesome when it comes to being long lived and making lower rpm torque for there tech of that age. We have a wrangler my daughter drives an 02 that has almost 300K and does not burn a drop of oil. But these 4.0s have one issue you see all the time on the forums and its the largest gremlin issue you could ever see. They seem to start cutting out or going into limp mode when you pass a certain RPM and you get all these multi cycl failure codes. This correctly points to the Crank position sensor (CPS). Its located on the top of the bell housing. People go buy the $20 one from china mart auto store and it seems good for a day maybe or two or not at all. The issues come back. Knowing they have done that sensor so it must be good right!?! (NOPE) they go on to cam sensor, throttle sensors, coil packs spark plugs etc. They will even take it to the Jeep dealer who tells them their head is bad and needs to be rebuilt In the end its almost always that the sensor they replaced did not have as powerful a magnet in it as the oem or it was positioned incorrectly in the sensor body ( too far away or offset) ( Its a basic hall sensor.) So when rpms pick up and the flywheel is turning faster it misses the PU to create a signal/voltage change. They spend thousands for what a $180 sensor, which yes is 5x what the china mart one cost, would have saved them that month down and thousands of dollars. Whats worse is now they have replaced known good sensors and coil packs with all these aftermarket china crap sensors which all could be failing or causing intermittent issues. Now they are really in a tail spin. I have seen people sell off there vehicles for cheap or throw in a remanf engine because of this. I have helped people with these and the first thing I do is replace every engine exhaust sensor with OEM ones or known exact same part.

If you want to ensure no issues of a failed sensor not coming back as well as it working properly and not chasing your tail just bite the bullet and use OEM Toyota sensors.when they need replacing unless you know for sure that a certain brand and part number of a sensor is very good which does happen. Otherwise understand its a crap shoot.

So just a warning about using those china mart auto store aftermarket sensors. IMO there are tons of places to save money on vehicle upkeep over the OEM, Filters, Fluids, Tires, Shocks Brakes etc but not engine power train electronics.

PERRYinLA

I don't think that'll be debated much. Thanks for sharing your experience.

And, to the OP - your car is an '07. Just because you've only owned it a month doesn't make it "new".