1993Ls400s

I replaced with oem wires. I know the maf cant be bad, just got a refurb one the other day after trying 3 or 4 other ones. i am going to order a ecu monday, thats all thats left besides O2 sensors, i have basically changed everything already... thanks for attachment, will check it out.

nthach

Take it to a mechanic who knows DAMN well what they are doing on Toyota/Lexus, find a shop that specializes in Toyota and Honda and you'll be set.

19psi

well, it's not your maf then. you may have a good sized vacuum leak.

i was actually just in e town saturday. had to drive to leitchfield to buy a turbo eclipse and tow it back.

1993Ls400s

But if it was a vacuum leak the car wouldnt run great with the maf unplugged would it? it even shifts allot smoother with it unplugged, i am going to order a ecu today, i am about positive thats what it is, well either that or the O2 sensors, but i would think the check engine light would come on if the o2's was bad. Yea, i have been to leitchfield to a junk yard and got a few parts for my friends Ls a few years back.. Hope the eclipse turns out good for ya man.. Sounds like a good project car..

19psi

it could run better since when the maf is unplugged the engine runs off a base map which is richer than it normally would be.
it's easy to check for vac leaks. get a can of carb cleaner and spray it around all the vac lines and intake manifold with the engine running. if the engine speed changes when you're in any particular area, that is where your leak is.
yeah eclipses are fun...cheap and easy to work on and easy to make fast. i've had about 8 of them over the past few years. this one i'm putting together and trading for an off road jeep cherokee.

1993Ls400s

Thanks for the idea, i will try that today. And have fun with the eclipse

1993Ls400s

Well, no Vac leaks. Will order new ecu later today.. Is it Ok if i leave the maf unplugged and drive it? or will it hurt Catalytic converters?

Och

iTrader: (3)

I find different results with driving when MAF is disconnected. Sometimes the car just runs perfect and perfect, but sometimes it starts pinging and loses power, and sometimes it idles way too roughly. It is probably affected by outside temperature/engine temperature, because when MAF is disconnected, your ECU is actually ignoring all the sensors that control A/F ratio - O2, MAF, ECT, IAT.

1993Ls400s

whats ect and iat?

nthach

ECT=Engine Coolant Temperature sensor
IAT= Intake Air Temperature sensor

The ECT is a thermistor whose job is to tell the ECM how hot the engine is and it is a input for the ECU/ECM/PCM to help it determine to adjust the amount of fuel being injected - and also to determine when to trigger the EGR and EVAP systems.

The IAT works almost like the ECT sensor, but it informs the ECU on the temperature of the incoming air charge.

Och

iTrader: (3)

Yep, in our car the IAT is actually a part of the MAF. ECT is a separate sensor on top of the engine.

minisiu

i think i get the same problem

it happend right after i changed my ps pump and altenator



get 2 problems
nit charging right only read 8.14 v it maybe run off from battary

and rough idle it idle at 1000 rpm and down and up to 2000 rpm and keep going up and down

i did try to unpluge the mafs and it idle fine

and i am going to charge my altenator again today see it is charge right

if not i dont know what is going on !!!

1993Ls400s

I got to thinking when i seen his post on the alternator, My lights get dim and my blower goes down lower when i push the breaks. my ps pump has a leak,could that mess up my alternator and cause this bucking?? also, that temp sensor you all mentioned, could mine be bad? where do i find it? i see a sensor on top near water hose with one wire to it, i unplugged it and when i did my temp gauge goes down to cold. so i didnt know if this was the right coolant sensor or not... thanks everyone..

Och

iTrader: (3)

The sensor that you unplugged is actually a temperature sender, for the gauge, theres another one right next to it, thats the coolant sensor.

1993Ls400s

Thanks man, I will go look for it, Thanks for all your help och, Together maybe we can fig out the problem with our cars since we have almost the same problem. did u check ur temp sensor?