Fuel Cut disable/delete??? ST185

Selsvik

New member
Its now on 137 000km. Oil change every 5000km, with filter every 10 000km. So the engine should be very healthy!
I am the third owner of this car :)

Btw, i was Just out testing after resetting the ecu.
It is much better!! The AFR is still a little high thow. 10 ish on third gear, and down to 9 on fourth gear.
I will purchase some silicone Intake hoses, and test more when i have that. :)
Does it make any difference if it's running on 95octane or 98octane?
 

alltrac801

New member
Selsvik":1lbodj5l said:
Its now on 137 000km. Oil change every 5000km, with filter every 10 000km. So the engine should be very healthy!
I am the third owner of this car :)

Sounds like you have a damn nice car then! My car has 239K miles so every time I would replace a hose or anything I would find another cracked or something so I just replaced everything hose related so I didn't have to worry about it.

Btw, i was Just out testing after resetting the ecu.
It is much better!! The AFR is still a little high thow. 10 ish on third gear, and down to 9 on fourth gear.
I will purchase some silicone Intake hoses, and test more when i have that. :)
Does it make any difference if it's running on 95octane or 98octane?

I have been running 88 octane non-ethanol with Lucas octane boost and I get decent gas mileage and the car seems so run good enough. In Utah we are a higher elevation so 91 is our premium but I cant find 91 non-ethanol.
 

Selsvik

New member
I live in Norway, here we have 95octane or 98octane(premium)
I dotn know what Oil i use, since i had in in a Toyota workshop last Oil and filter change
 

sefiroxx

New member
(NOTE: European octane rating is different than US. 98 Europe is roughly 91-92 US. 95 would be similar to US 89)
 

Selsvik

New member
i have now fixed the intake hose, replaced it with silicone hose. pretty sure everything is tight now.
But the problem is still there... it still doesn't like boost over 0,7bar ish.
not sure what to do next... have other peolpe experienced this?
 

underscore

Well-known member
Anytime I repair anything, I reset the ECU by removing power for a few minutes to clear any bad habits it may have learned before proceeding. Hopefully that's all it is for you.
 

Selsvik

New member
i have tried this several times... unfortunately this does not do the charm for me :/
I have notised that the car is using a little bit oil. could that have anything to do with it?
 

underscore

Well-known member
Derp, I just noticed I already suggested that to you, sorry about that. Is it just struggling to build more boost than that or is it suddenly cutting power? Does the CEL work and are there any codes?
 

Selsvik

New member
It feels like it is cutting the fuel a bit, but it runs too rich. It has no problem getting up to 1bar of boost, it just shakes alot because of the rich mixture of fuel or it cuts the fuel or something Else. It accelerates good until i reach 0,7bar and then it struggles a bit to keep accelerate.
What do you mean by CEL? and if there is any codes?? Do you mean "check engine" codes?

Yesterday the engine light came on. Dont know why... I turned the car of, took off the battery for a couple of mintes, but the check engine light didn't go away. So it is now at home with no battery hoping that it will dissapear.
Also when i parked i looked in the engine and saw the turbo was red hot :eek: dont know if this is normal with these cars or if that could be the cause of the check engine light?
 

underscore

Well-known member
Selsvik":1vg8vyqm said:
It feels like it is cutting the fuel a bit, but it runs too rich. It has no problem getting up to 1bar of boost, it just shakes alot because of the rich mixture of fuel or it cuts the fuel or something Else. It accelerates good until i reach 0,7bar and then it struggles a bit to keep accelerate.

Sounds like it's either getting too much fuel or it's losing air somewhere or the computer is detecting a problem and pulling timing. Or the computer itself is having problems, given the age of them they're all due for having the capacitors replaced as they will start to leak (can cause even more damage) or dry out.

Selsvik":1vg8vyqm said:
What do you mean by CEL? and if there is any codes?? Do you mean "check engine" codes?

Yes, the light is supposed to come on with the key turned on (not running), then once started it should turn off. If it isn't doing that you've got a problem with the bulb or the wiring or the ECU. If it is working correctly then check for any codes (the list of codes is around here somewhere) and go from there.

Selsvik":1vg8vyqm said:
Yesterday the engine light came on. Dont know why... I turned the car of, took off the battery for a couple of mintes, but the check engine light didn't go away. So it is now at home with no battery hoping that it will dissapear.
Also when i parked i looked in the engine and saw the turbo was red hot :eek: dont know if this is normal with these cars or if that could be the cause of the check engine light?

Why are you trying to get rid of a diagnostic code that could be telling you what the problem is? Always read the codes before clearing them. The light is telling you the computer detected a problem and it has a code for you to tell you what that is.
 

Selsvik

New member
That is actually a valid point... I have an appointment on friday at the workshop(Toyota). Maybe they can look what the code was for. I've heard that the ecu has all check engine codes saved in their memory (Y)
 

underscore

Well-known member
It stores any codes that have come up (even if the CEL is currently off) as long as there is power to the ECU. If power is removed they get cleared.
 

Selsvik

New member
Small update... The workshop found out that the engine light was the knock sensor. They think that it has been set off because of all the shaking from the rich mixture.

Then i found a possible leakage, and fixed it. It now runs on 10-11 instead of 8-9 when full throttle.
So thats good. But it still runs a bit rich, and the engine light wont go away...
And after the engine light has Come, it runs really bad... So im Wondering if anything has happened when the knock sensor went off.
 

underscore

Well-known member
I've dealt with the knock system far more than I cared to while troubleshooting my car. The wire can be internally shorted or broken, this can be tested with a multimeter. The sensor itself can also fail and not send any signal, either right away or once warmed up a bit. In the end I replaced the wiring all the way from the sensor to the ECU twice (be sure to use correctly shielded wire, or you can steal the wiring from another Toyota) and replaced the sensor twice and I haven't had an issue since. When the sensor cut out randomly when warm I'd have to clutch in, shut the engine off, restart, clutch out and keep going til it happened again which is a REALLY annoying way to get around town.

A friend with a turbo MR2 also had knock issues, he kept replacing the sensor before figuring out sloppy motor mounts were causing the problem, so make sure there isn't too much play in those.
 

sefiroxx

New member
Symptoms of misfire/knocks are common when AFR is off due to air or fuel leaks. It's possible the knock sensor or pigtail is going.

The high idle readings are indicating a lean condition most likely a air leak (or clogged injector).
 

Selsvik

New member
Yes, the lean mixture when idle was a hose that had came off. But i fixed that. So it idles around 14,7 now.
Must be another leakage on the vacum hoses... Tested the air Flow meter, no problem with that...
But what do you mean by "It's possible the knock sensor or pigtail is going." ?
 

Selsvik

New member
I will check with these engine mounts! I recently changed the rear diff Bush to a poly Bush. Its really stiff. And i can feel the car is shaking i bit because of that. So i will check that out too (y)
 

underscore

Well-known member
If the sensor is failing, or the wiring is faulty, the ECU assumes worst case scenario and pulls timing, dumps loads of fuel, etc and basically becomes as safe as possible but also absolutely gutless.
 
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