After Clean The Throttle Body And Maf

[littlemouse]

After I clean the throttle body and MAF on my 92 LS400, the RPM start a little higher then 1000 and idle roughly. After 30 second, RPM start decrease (I can feel the car is shaking) then engine die. start it again and it die within 10 secounds. I wait for two hours and try again same thing happen (RPM start a little higher then 1000 and idle roughly. After 30 second, RPM start decrease then engine die.)

I unplug the MAF sensor nothing change.

I use CRC mass air flow sensor cleaner and CRC Throttle body & air-intake cleaner

Any one know why?

[chilkoot]

did you just spray the aerosols into the intake, or did you disassemble anything?

[python]

sounds to me like a vacuum leak

[eatingupblacktop]

sounds to me like a vacuum leak

That would be my first guess as well, since you didn't have the problem before cleaning the TB. Did you use a new gasket and are the surfaces clean? I would look there first.

[littlemouse]

did you just spray the aerosols into the intake, or did you disassemble anything?

I clean it like this

sounds to me like a vacuum leak

How do you check it?

How to fix it?

when I removed the parts I see the silver stuff between it, is that something to prevent air leak?

why it is fine for the first 30 sec? :(

[mburnickas]

CRC for the MAF is fine. I was happen you did not say seafoam here.

Is the engine cold or hot?

[littlemouse]

CRC for the MAF is fine. I was happen you did not say seafoam here.

Is the engine cold or hot?

Should I try seafoam?

Engine is cold.......it die too fast.....

no help when add gas.....

[jcrome04]

Seafoam worked miracles in my car. It was awesome.

Here's a DIY I made if you're interested.

http://us.lexusownersclub.com/forums/index...showtopic=44922

I don't know if it would FIX your problem, but it wouldn't hurt to do it.

[lexfourcam]

sounds to me that you damaged your maf sensor while cleaning it. ive done so and replaced it and it worked fine. mafs are very expensive too so make sure to check on ebay b4 u go buying one. i got mine for 170 bucks

[Threadcutter]

After I clean the throttle body and MAF on my 92 LS400, the RPM start a little higher then 1000 and idle roughly. After 30 second, RPM start decrease (I can feel the car is shaking) then engine die. start it again and it die within 10 secounds. I wait for two hours and try again same thing happen (RPM start a little higher then 1000 and idle roughly. After 30 second, RPM start decrease then engine die.)

I unplug the MAF sensor nothing change.

I use CRC mass air flow sensor cleaner and CRC Throttle body & air-intake cleaner

Any one know why?

Did you put everything back together, or are you expecting that the engine will run properly with the air ducting between the MAF and the throttle body removed?.............It won't.

If the ducting is not put back in place, there will be no airflow over the MAF, hence the MAF reports back to the ECU that there is no airflow and the engine will die.

With the ducting removed, unplugging the MAF won't make any difference..........

I wouldn't entertain the idea of buying a new MAF (or anything else) until you put everything back together properly and try it.

The less you screw around with the MAF, the better. The leads coming off the MAF bulb are very delicate and it would be easy to break one of the leads, then you ARE screwed.

[littlemouse]

I end up change the electronic unit (MAF, AFM) only and it's all good now....

I bought two MAF..... just in case...

Now I need to sell one....

I pay $100 + for it and now selling for $90 shipped

PM me if anyone is interesting on it

[wwest]

My '95 LS400 w/211,000 miles just got 27MPG (14.55 gallons) on a 390 mile round trip with an average moving speed (Gamin) of 67MPH. I suppose I should at least put in new sparkplugs....