Mkiii Supra Turbo Engine Light Keeps Coming On....

[mobee]

HI CAN YOU HELP, I DROVE MY CAR THIS MORNING AND IT WAS FINE, BUT I JUST CAME HOME IN IT AND I PUT MY FOOT DOWN

AND EVERYTHING WAS FINE IT SPED UP NORMALY THEN ALL OF A SUDDEN IT LOST POWER AND THE ENGINE LIGHT CAME ON, WHEN I LET GO

OF THE THE GAS PEDDLE AND LET IT SLOW DOWN THE LIGHT GOES OFF..... PLEASE TELL ME WHAT CAUSES THAT I AM NOW AFRAID

TO DRIVE IT.

THANK YOU

[Steigers]

Have you read the fault code for it? Have a look at this it may help......

http://www.cygnusx1.net/Supra/Library/TSRM...=FI&Page=23 (Thanks for the link RoadsideTech if you see this :D )

You don't need the SST, just use a paper clip. Then count the number of flashes the ecu light is making and look at the codes a few pages on in the manual.

Hope it's nothing to serious

[Karma Supra]

Fuel cut.

Sounds like you are boosting too high (approx 11-12 psi depending on air temperature) of you have a poorly configured air fuel ratio controller.

[Mik_D]

There could be a loose connection to a sender unit beneath the inlet manifold. This is the knock sensor. If the connection is loose or intermittently grounded then you get the exact symptoms you describe. (It could also be other things - but this is an easy fix- although a bit of a bugger to see and get to-you will need a mirror and a light. By the way - same thing happened to mine and I was scratching my head for some time until I noticed the free wire dangling!)

[Karma Supra]

I'll put money on it not being a knock sensor.

There are two of them too ;)

An air leak could also give fuel cut symptoms.

Either way Steve's fault finding tip will diagnose the warning light.

[Steigers]

My ECU light is still on pretty much permanently after a Toyota dealer gave the knock sensors the benefit of there un-wanted attention - no bad running symptons though. Should get it sorted really

I gave myself fuel cut type symptons by not tightening up all the inlet manifold bits though after a head re-torque, i went into panic mode for a bit - Charlie helped me out on that one

Hope you get to the bottom of it mate

[mobee]

THANKS GUYS FOR YOUR VIEWS, I AM GOING TO TRY ALL THE THINGS YOU SUGGESTED AND ILL LET U KNOW IF THEY WORKED.

ONLY THING IS IVE BEEN TOO BUSY.

THANKS ALL.

[mobee]

i took it to the shop yesterday and they said it could be the air flow meter or 1 of the vacuum pipes have got a slit in it, only thing is it's like looking for a needle

in a haystack situation....... i drove it yesterday and learnt that when i floor it and let the gas off a bit before the gear change it is fine but if i keep my foot planted it will always do the power loss for a second and management light, does this help you guys with diagnostics, oh and speaking of diag where is the obd plug located or isn't there 1??

[Karma Supra]

Ho hum.. looks like I was right again!

If you have an after market enxuast or have upped the boost in any way, Its boosting too high.

If you don't it'll be an air leak as suggested. Check the factory BOV is not jammed, and it that proves ok check that the no.1 turbo hose is not split at the turbo end (runs from the cold side of the tubo to the indercooler, before the 90 degree joint)

What is the boost gague reading when the fuel cut hits?

[mobee]

to be honest with you karma i haven't took any notice, when i take it out tomorrow i will check and let you know

what the boost gauge is reading and i'll check the pipes as well....

[mobee]

HI KARMA, RIGHT THE BOOST PRESSURE IS AT + .4 ON THE GAUGE WHEN THE PROBLEM OCCURS.

WHAT DO YOU THINK....

[Karma Supra]

but .4 do you mean 4 psi, Fuel cut doesn't kick in until way after that (although it varies depending on ambient temperature) if anything that is boosting low, should be nearer 7, (assuming factory exhaust etc)

It'll be a leak somewhere. Did you check the no.1 turbo hose as described?

[mobee]

yes +4 psi, no i totally forgot about the hose i'll check it and get back to you mate.