Lexmex

No, there isn't, it's all connected through the normal ECU.

Lexmex

I believe that is related to the headlights (the particular missing 15 amp fuse).

salimshah

Talking about fuel pump, is ti regulated by the ecu? The ecu or something has a safety cut out for the fuel pump to prevent pumping in case of an accident [typically connected to the spark activity].

I am used to fuel pumps regulating themselves by maintaining line pressure [the more the demand the more they pump].

There was a post that I read implying the ecu is controlling the rate of pumping.

Salim

Ymmot

The reason i ask this is because i found this link https://www.clublexus.com/forums/per...-pump-ecu.html i thought maybe i got that thingy also on the rx300

Lexmex

There is a regulator piece on the pump itself, but as far as something akin to what he is showing in that link to the Lexus SC, no. It's ECM in the glove compartment.

Ymmot

This is the codes from this morning ...they say all the specs look okay but i have a feeling they dont have a glue about what they are doing ..they got the it2 tseter though im just not experienced enough to read it and neither are they ..they advice me today to change the plugs ..but to me seems like i have a faulty MAF sensor ?..ow btw they dont have plugs on stock also ..

Lexmex

Next time you go check with the scanner, have them disconnect the battery first, then start up the vehicle and wait about 4 minutes and see what codes pop up.

Yes, the P0100 and P110 codes relate to the MAF, but make sure there is rubber O-ring seated beneath the MAF sensor, sometimes people forget that after cleaning it.

Ymmot

Im sure the O-ring is there...does it make sense that i change MAF b4 sensors on bank 1 and 2 ..
My thinking was like if my MAF dont give correct readings the A/F sensors will ofcourse report fail since mixture aint correct ?

I see some mark "!" infront on A/F reports on the scanner do they mean anything special ?

Thanks for the reply Lexmex

Nad1370

The "!" means that a freeze frame was saved
Meaning it took a snapshot of a recorded parameter when the code occured.
Seeing they both were AF codes. Probably their voltages were out of range.
Fuel trims might be recorded also.
There should be a freeze frame data on that scan tool you have.

Those 2 codes for the MAF meter kinda bugs me. Usually an unplugged MAF with the key ON would trigger those codes.It's possible that when they were checking codes that they left the MAF unplugged.

Clear those codes and see if they come back.
But before that. See if you can post the freeze frames that were recorded. I'm curious.

Ymmot

The IT2 scanner is not mine its from toyota they saved the file but i think im gonna find another workshop where they have the tool and someone that understands reading it.. the maf was plugged in 4 sure ..if i disconnect it car will stall and not run in idle..

I will try and see if i can get those data when i go there to pick up my airfilter ive been waiting for 2 weeks now ..should be in this week for sure

Lexmex

Doesn't make a difference whether you change a MAF before A/F sensors or not.

Ymmot

Update ...my problem seems to be closer to solution ... i got the fuel filter changed helped quite a bit with more respons from the throttle...today i changed the dogbone mounting it also helped mainly on the vibrating ...the mechanic who changed the fuel filter told that because the ridicolous quality of fuel here he often seen error codes on a/f sensors and since i guessed that the fuel filter never got changed i change that just to rule that thing out ....im going back to he workshop i a couple of days to see if the codes remain on the a/f sensors ...my guess is that the code will stay ...i tried to measure on the sensors since they should have a resistance between 0.8 - 1.2 "as i remember" at 20 degrees celsius and i get no reading from then when i checked so if im not wrong the problem was 3 things ..a partly cloaked fuel filter ..a broken dogbone mounting and the af sensors which still aint changed but the allover symptoms is a lot less now that the other things has been done

Ymmot

PS...On the last reading i got 3 days ago b4 changing fuefilter the error on maf was not there anymore

Ymmot

Sensors didnt do the trick to get rid of the stagger i had ...culprit was fuel pump changed it and now ride is smooth ..i now its an old link but i hate ppl that dont finish the thread ..so in case anyone ends in same situation start with fuel pump

Nad1370

Just as I suspected in an earlier post:

Glad you finally figured it out.
Just made sense to me that it's a fuel issue more than and air or sensor would cause your problems.