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Help - my soop is sick!!


steve spedd

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:help:

 

Please if you have any suggestions let me know, as I have none!!

 

Ok morning folks, my car has recently felt like its lost power. It seems to be a bit down on power but then above 5-5.5k revs the power loss is quite bad. the only way I can really explain it is its like driving a diesel car, you know when no matter how much u rev it it just wont go any faster. I have had a new air flow temperature thingy fitted (located on the induction kit) and that has made it rev better up to the second cam coming on (5-5.5k ish) but not helped above that.

 

I have read about people cleaning the O2 sensor, im not sure if that will help as I have no idea what it does (bit thick!!) and also would replacing the fuel filter help??

 

The fuel economy does seem to have gone down which does make me think it could be a fuelling fault...

 

That’s about as much as I can tell you. I would really appreciate as much advice as you can give me please...

 

:thanks: a concerned Steve!!

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Hi Mate,

 

You may as well clean the 02 sensor to see if it makes an approvement. Very easy to remove it is on the down pipe and has simply 2 nuts (think 10 or 12mm) undo then put the sensor in lemon juice for around an hour. Then dry and put back in.

 

Do an ECU reset and see how it goes, might as well it rules out the sensor then. Also maybe a take a pic of sensor when you take out so everyone can tell you if it coated in to much carbon or its normal.

 

sorry cant help more

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Im not sure,

 

Covered near base more then mine were, but at same time i have seen alot worse!!

 

how many miles has the car done?

 

When they come off there lemon soak you'll see all you can see is metal, to be honest you will find out if its them within a couple tanks of fuel or not.

 

Also when were your spark plugs last changed?

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Steve, if they are the original ones or haven't been changed in years then I would definitely change them, they may not be the cause of your problems, cleaning them may help short term, but if they are worn they should really be replaced

 

I am currently organising a group buy for brand new O2 sensors at very good prices compared to UK Toyota prices, see link in my sig below.

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thanks, the look pretty clean now. just gonna put them back on. see how it goes. not sure on the plugs august i think. about 3000 miles ago.

 

if this feels any better i will probably invest in some new ones.

 

Nic,

 

does the price (69 i think is says) is that for one im guessing? do the TT's only one o2 sensor?

 

and would changing the fuel filter make any difference?

 

thanks for the help guys...

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ok, i have put the sensors back in , reset the ECU and taken it for a spin, went for 10 miles under 4000revs and then thrashed it. still have the same problem.... SHIT!

 

any ideas what it could be. Nic would replacing the sensors fix the loss of power at 5.5-6.5k revs?

 

really have no idea what i can do.

 

i would be greatful in anyone has and ideas!

 

thanks steve

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ok does the problem happen in all gears, if your sat in 2nd at 2000rpm and go to redline is pwoer fine, then if you do it in 4th do you lose power.

 

does it sound like a misfire at all? Have you changed your exhaust, when i changed mine on my NA i lost the sudden surge you get as i have more low down torque.

 

What plugs do you have in there, i think seeing as your an NA like me and you can get plugs for about £15 tops id change them anyway

 

Its not your sensors if you still have problem, to be honest that was just to rule them out

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1st seems ok, 2nd is slightly worse 3rd and 4th are really bad. cant redline in 5th as im still limited...

 

exhaust is a nur spec. just the back box and has been on since i bought the car.

 

i did get the back cat removed but that shoul only improve things, right?

 

no idea what plugs, they were put in when i had it serviced. what make do you use? dosent sound like misfire...

 

saw this didnt know if it was worth doing:

 

http://www.mkivsupra.net/vbb/showthread.php?t=35920&highlight=check+error+codes

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hi mate, look at this thread for plugs

 

http://www.mkivsupra.net/vbb/showthread.php?t=41927

 

go half way down post and you'll see your choice!

 

Id just go standard plugs or V-power. We wont see much gain from better plugs as NA.

 

I think its worth changing them, As the spark may be weak, do you get a smell of petrol at all?

 

Yes you can check for codes, may tell you what sensor has broke if any :)

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I had the exact same thing yesterday. Was driving to work and in 2nd gear at about 4k rpm it just seemed to die. If I let off the throttle abit and then gently accelerated it was ok. Happens in all the gears as said above. I can be crusing in 5th at 50 say and if I put my foot to the floor it sounds like I hit a weak rev limiter for a few seconds. Weak meaning as in its trying stop you but just manages to go up the revs slightly.

 

Then this morning when I came to leave work it wouldnt start. Cranked it over 3 or 4 times and nothing. Tried 30 seconds later and it fired up straight away but I still have the misfire at the same point again - foot to the floor it misses, gentle accel is ok but abit rough.

 

Any ideas people?

Cheers

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Steve, make sure you have no leaks in your exhaust system as it can affect the working of the O2 sensor.

BTW sensors should be changes at 45-60k. They are a service item. Their performance drops off slowly and even a regular driver of the vehicle would have trouble noticing at first. Cleaning them won't help if they are on the way out.

Lucas website have a comprehensive write up on them.

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Removing those middle two plugs is a right pain in the a$$! Unfortunately no easy way, Gotta remove everything above. Just start from the air box and work backwards there is a really nice guide I found and think I posted it on here. I'll try and find it for you.

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thats great, thanks!! some really good stuf. just one question. did you replace any of the gaskets when you replaced your plugs?

 

thanks Steve

 

You are supposed to change the gaskets, but I was really really careful when removing them, they looked pretty perfect to me, so re-used them. Hasnt caused me a problem. Although if your ordering some plugs, might be worth getting a couple of gaskets too. ;)

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Had a chat to Toyota parts and I think I only need one gasket. gonna order to tomorrow and hopefully have a go at the plugs next weekend.

 

When people refer to the 'dizzy cap' im guessing that's the distributor cap right?

 

Any idea where I should be buying the gasket and other standard parts such as ht leads, fuel filter etc??

 

Cheers for all the help. :respekt:

 

Amazed how helpful the people in this club are. Going to have to get to some meets this year and meet some of you!!

 

:D

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that is correct, the gaskets are reusable. (ive read it on here before) But like you said 1 may need replacing but you can get away without replacing it.

 

I buy things, like Fuel filter...oil filter etc... from Part Co or toyota if cant get them. Mainly Part Co because they are cheap on blue print products.

 

Dizzy is distrubtor cap, whilst replacing that replace the rotor arm, it spins round in the cap hitting the points to send the spark, chances are its nothing to do with that, but it will probably be sub £5 and also very easy to replace (pull old one off....push new one on)

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