deanshark

By disconnecting the AFM all that does is put the ECU into limp mode. It will then run better and have so so so much more power but will run really rich. When my AFM was bad in my 93 when I had it plugged in the RPM would go well over 3K, when I unplugged it, it would run better then new. With these cars being 25-30 years old Lexus doesn't worry too much about them. Most guys at the dealers now know more about todays cars. They probably weren't even working yet when these came out.

ForzaRoma

Very true. They should be more knowledgeable though. They should be just as knowledgeable with the old cars just like the new models. They can never give me any info when I do ask them. We have a few Lexus dealerships her in San Diego and everytime I ask a question to any of the dealerships here. They just say sorry, I don't know the answer. Which sucks if I am being honest.

deanshark

That's how it is with the older cars. I'm not judging anyone but most of these younger guys only know how to plug in a computer, not actually turn a wrench. And if they're working on some kind of commission, forget about it, you ain't getting two words from them if they're not gonna be working on your car.
I'd rather go to some run down, messy independent shop with two 60 year old guys sitting out front drinking and bull****ing then a dealer. Those are the guys who actually work.
Good luck with the AFM. Like I said, I'd rather get it from a junkyard and pay shipping. (with a return policy.)

ForzaRoma

Haha. Yeah, I hear ya man. Yeah, I'll just try buying another used OEM with a warranty and hopefully that will solve my problem. Thanks for the info. and your feedback. I really appreciate it. It is great to get some feedback from fellow owners of these old Lexus cars. Which I personally prefer over the newer ones. I don't really give a rats *** about all of the bells and whistles and technology. Nor do I like the look of the overkill gaudy front grilles of many of the new models. I just care to have a good, clean, dependable car with rims, tint and stereo. That's all I care about. Haha. Thanks again for the info. to both you and Lex2K users I had today. God bless you both.

CELSI0R

Just want to share to clarify any confusion that might arise in the future.

The 1990-1994 LS400 uses a Karman Vortex AFM. This should never be cleaned with CRC MAF cleaner, and really only compressed air.

Note on some ES models with the same style sensor:
https://www.clublexus.com/forums/es-...ml#post7712871

Here is how you can test yours:
https://easyautodiagnostics.com/misc...-sensor-test-1

YODAONE

While the Karmen Vortex AFM (1990-1994 LS400) appears more complex than contemporary MAF (1999 LS400), which is the better part? It appears we have frequency vs resistance output.
My sense is frequency output vs resistance would be more consistent over time...

LeX2K

AFM flap style that controls a resistor is way less accurate (and slow).

ForzaRoma

Thanks for the info. That is what started this mess for me is when I cleaned it with the CRC. Thinking I was doing something good for my car. Instead, I just broke it. I ordered a replacement OEM one on ebay yesterday with a 30 day warranty. I will definitely not be cleaning this one!! Crazy how you can't clean the old ones but you can clean the new ones.

deanshark

That's what made my AFM go bad on my 93. When I first bought my 93 (way back when) I didn't know the same thing. "Don't clean it" All the research I did on the car, I missed that. Oh well, live and learn. Hope the new one works out for ya.

ForzaRoma

Yeah. Me too! Thanks man. Have a good holiday

ForzaRoma

UPDATE: After having issues with engine hiccups and jerking at high speeds with my 1992 Lexus LS400. I replaced my MAF sensor with another OEM sensor I bought from a junkyard on Ebay and my car NO LONGER jerks. Drives like new again and very smooth how a LS should be. If anyone reads this post, I hope it will help someone else that has the same problem I had. My advice, NEVER clean the MAF sensor in the older Lexus LS models. YOU WILL have problems!

ForzaRoma

UPDATE: After having issues with engine hiccups and jerking at high speeds with my 1992 Lexus LS400. I replaced my MAF sensor with another OEM sensor I bought from a junkyard on Ebay and my car NO LONGER jerks. Drives like new again and very smooth how a LS should be. If anyone reads this post, I hope it will help someone else that has the same problem I had. My advice, NEVER clean the MAF sensor in the older Lexus LS models. YOU WILL have problems!

peterls

I just found OEM MAF for 1st geb LS on amayama - 700 bucks for the entire assembly.

ForzaRoma

I got mine much cheaper! I only paid $67 with shipping