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MOT Failed - Emissions CO high --- Door closes and engine almost stalls.


Tayfun.tugra

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Hello, how is everybody?

 

went for the MOT today and a few things were wrong with the supra which i really didn't expect.

 

I start the story from the beginning and try and make it as clear as i can and try not to miss anything out. I've tried to highlight the main things...

 

Car: 1995/1996 Supra TT Auto BPU Import. new oil, new spark plugs.

 

 

Last year I took the supra out of the garage in which it was stored for 2 years prior in hope to get it on the road but it produced a problem, (struggling to accelerate above 70mph, acceleration would be fine under 70) a spark plug that got passed my initial inspection was replaced and sorted the problem out. The car was then driven for a further 15 miles with no problems, stored in the garage for another year with the occasional start & drive out the garage onto the driveway for a wash and back in again. The car passed its Emissions test in 2010 and no mods or performance changes after.

 

Just today was my first drive more than 20 meters in 1 year. Filling up with tesco momentum 99 and a few drops of redex, I drove 22 miles to the MOT Station and 22 miles back, the problem is similar to last time (struggling to accelerate above 70mph) but this time acceleration is struggling any mph half depressed acceleration. puffs of Black and white smoke (sometimes black, sometimes white when accelerating, Air filters washed and clean)

 

I've checked and rechecked the spark plugs they are clean and look ok. I'm suspicious of a coil pack so i'll check them tomorrow as my neighbour has kids I really don't like to make much noise after 17:00. The important bit is below..

 

MOT Door Closes engine drops idle ---

As the MOT tester was checking around the car, seats seat belts and such. When he shut the drivers door (didn't close that hard) the car almost stalled from an idle 700-800 rpm down to around 250 rpm or thereabouts and then put itself back up again. I've been taught to think how the ecu would think, but why would the car drop the rpm? fuel cut from vibration of the door closing? would it be that wiring is loose from the ECU or bad ground? or any of the sensors? My first thought was battery terminal connections, but they are ok....so the MOT guy wasn't happy as it happened more than once during the MOT, but he done the emissions test anyways.

 

MOT Emissions ---

The were to attempts, the first was a basic one, stick the probe in the exhaust read the numbers...it failed. The machine said to check the oil level with the oil probe, it came back satisfactory. The second run being an extended emissions test 120 second 2000RPM? & a 2500 - 3000 rpm, the machine then said let the car idle for 30 seconds with probe out the exhaust, and a further 10 second idle run with it in the exhaust... CO (carbon monoxide) was high in normal test (assumingly passed the fast idle to continue to the normal idle) . The max limit was 50 it was reading 65 and dropped to 53 in the last test time (10 seconds).

 

Suggestions from the mechanic were to:

give the car a good strong drive at high RPM and come back in a few days, but as the car has no tax or mot, its very realistic that can land me in some serious trouble.

check exhaust,

Possible Turbo is going

Plugs

but he also stated he won't touch imports, and to be quite frank garages around me won't have a clue, they'll play with everything ruin everything then give it back more broken than it is and say you got a serious problem there mate... and then hand me the bill. I would take it to the college but the garage is closed till the 9th.

 

has anybody experienced the RPM loss when closing doors or knocks? Emissions CO high?

Any help would be greatly appreciated.

Thanks

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could be a number of things. siezed actuactors and things in the turbo system. dodgy vsv's. iffy coil packs/clips. split/popped off intercooler pipework. mostly related to a 20 year old car sitting idle for so long. who knows what pipework could be split or perished.

But from your story id say you need to get all that kind of stuff checked out and then start driving your bloomin car. it does a car no good to just be sat in a garage rotting away year on year. and if all you ever do is get it olut of the garage to wash it and drive it to the mot station your just throwing money away at the taxman and its taking up space :)

Personaly if i had the choice of buying a car, one which had been sat in a garage for 4 years and had covered a few hundred miles and a car that had been used every day and was 150k miles id choose the latter.

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Thanks guys i'll be looking into all of that tomorrow morning.

Regards the idle speed and suddenly dropping then I had similar symptoms when my idle control valve was playing up, I replaced it and it's been fine ever since *touch wood. I wonder if the door closing and it dropping is just coincidence?

It happened a few times throughout the MOT so I dont think its a coincidence, however I could not recreate it by closing the doors after I got home

 

but i think i know why the car had failed the mot test.

with thanks to this thread http://www.mkivsupra.net/vbb/showthread.php?291610-MOT-failed&highlight=emissions my car results...

"MOT Exhausts Emissions Test Results catalyst equipped vehicle with closed loop control"

Result

Engine temp = 71oC --Pass

Fast Idle --Fail

Engine speed = Manual Check - Pass

CO level = 10.44 % vol --Fail-- Limit = 0.30

HC level = 286 ppm -- Fail -- Limit = 200

Lambda = 0.729 -- Fail -- Min 0.970 - Max 1.030

 

Second Fast Idle --- Fail

Engine speed = Manual check -- pass

CO level = 0.64 % vol --Fail -- 0.30

HC level = 84 ppm -- Pass -- limit 200

Lambda = 1.025 -- Pass -- min 0.970 - Max 1.030

 

Natural Idle Test

Engine speed = Manual check -- Pass

CO Level = 0.55 % vol -- Fail -- Limit 0.50%

 

Overall Result Exhaust Emissions Test --- Fail ---

 

would anybody recognise these limits to be UK version cars? would they be the same as J spec? The results also seem to get better as the tests go on... From 10.44 % Vol CO level to 0.55 % Vol.

 

 

 

But from your story id say you need to get all that kind of stuff checked out and then start driving your bloomin car. it does a car no good to just be sat in a garage rotting away year on year. and if all you ever do is get it olut of the garage to wash it and drive it to the mot station your just throwing money away at the taxman and its taking up space :)

Personaly if i had the choice of buying a car, one which had been sat in a garage for 4 years and had covered a few hundred miles and a car that had been used every day and was 150k miles id choose the latter.

 

Somewhat very true. my father and I brought the car in 2009, at that point we had around 12 cars... 4 cars were parked outside the business, 4 in the driveway and garage and the rest on the street outside the house aha. (Supra, Jag xk8, Subaru impreza, Ford Scorpio, Vectra 2.5 V6, pug 106 GTI, pug 206, 3 series, 2 rover diesels, jeep cherokee and 2 Clios maybe one or 2 more..) almost all taxed, insured and MOT'd so really no time to drive them. What's the point I imagine you say... well my dad likes cars. However, we are now down to 6 cars and will only be left with 3 by the end of the year hopefully... (the supra, the jag, and a rover diesel for economy :rolleyes: )

but I would buy the former... who knows what scumbag has driven the car for 150k... Brake boosting, closing the engine without letting the turbos cool and such.

Edited by Tayfun.tugra (see edit history)
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Expose the ECU in the passenger footwell, get the car idling, and then grasp the main wiring loom firmly and move it around vigorously. See if it stalls or struggles then :) Easy test to see if you've got dodgy connections at the ECU, something shutting the door could cause.

 

Failing that it might be an earthing fault that's only there when the door is closed, i.e. a trapped/exposed wire.

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Wild guess but I would suggest it's the coil pack clips.

 

There is method to my madness though....

 

You checked the spark plugs - Coil pack clips off, coil pack clips on - Fault remained

You re-checked the spark plugs - Coil pack clips off, coil pack clips on - Fault fixed (my guess is the coil pack clip got a better seating this time, rather than the spark plug being at fault)

After a while you got an issue trying to accelerate - potentially weak spark - most common cause coil pack clips.

When you close the door the car struggles to hold idle - Vibration from closing the door jiggles the car enough for the coilpack clip to cause issue.

 

Quick check.... try passenger door, drivers door, the boot and the bonnet. If all 4 cause the same symptom then it's definitely something lose and getting jolted when the car vibrates.

 

Oh, you sould be able to check quite easily if you have a friend. Check that the issue occurs by opening/closing the door, if it does... hold coilpack clip one firmly onto the coilpack and try again, repeat for coilpack clips 2-6. If it is the clip then that should find the culprit.

 

Good luck :)

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Right, so ive got to the ecu and it looks in clean, solid condition, there's 2, the left which says 2JZ-GTE A/T with a fcd on it, and the one on the right almost double the size saying 2JZ-GT A/T 89...

Not sure what the E stands for done a few searches it just directs me to 2jz ge ...any advice if the ecu has common failures?

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Guest Roger NE

To be honest, not using a car is probably the worst thing you can do ! All kinds of things deteriorate . . . . not least of which all the electrical connectors on the various engine sensors . . . any of these playing up, like the TPS, CPS, etc etc could cause the kinds of problems you're describing. (as well as the HT feeds to plugs, as already suggested)

 

I would get some proper electrical switch cleaner and remove and clean all the connectors to the engine sensors.

 

The ECUs on these cars tend to be VERY reliable (apart from the 1JZ ones, which used very ropey capacitors)

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You maybe onto something there scott, if I remember correctly number 4 and 6 clips have broken..the bit you press in to release. But im in the middle of removing the carpet to check the ecu, once ive checked the wiring ill get onto that clip testing.

 

There's your problem right there. Happens all the time. The reason yours is struggling to run is because 2 of them are out the game. When one goes it just runs a bit funky sounding, when both go the car will struggle to pull/idle and will generally just stall.... been there and got the tshirt all dirty.

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Guest Roger NE

If you take the car back to the MOT place he should just have to re-check the Emissions, and not charge you.

 

Actually the place I have used for years DOESN'T charge you if a car fails . . . only when you've fixed any faults and bring it back does he check the repairs and then take your money in exchange for the MOT Certificate. That's why so many local traders use them, because if it's an old banger that's failed on too many things, you just don't bother going back!

 

They charge £40 for an MOT . . . and although there are places that only charge £25 I am sure they would always fail cars on lots of things !

Edited by Roger NE (see edit history)
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so ive refurbished all 6 clips and now they fit tight and don't wiggle. I cant recreate the dropping idle when closing doors, so i think its helped it on that point:)

 

Im now looking into the injectors, number 3 and 4 in particular and i think they need a bit of a clean

 

What issues do you have now then?

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What issues do you have now then?

The car still doesn't want to accelerate quickly, its like its throat is not clear, even though its getting better with time and a daily drive around the estate. A friend suggested to leave it idle for an hour to get the old petrol out of the system and fill up with fresh...any ideas if this will help?

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If you take the car back to the MOT place he should just have to re-check the Emissions, and not charge you.

 

Actually the place I have used for years DOESN'T charge you if a car fails . . . only when you've fixed any faults and bring it back does he check the repairs and then take your money in exchange for the MOT Certificate. That's why so many local traders use them, because if it's an old banger that's failed on too many things, you just don't bother going back!

 

They charge £40 for an MOT . . . and although there are places that only charge £25 I am sure they would always fail cars on lots of things !

 

I have 10 days to get it re tested from my first test day for it to be a small charge because I left the mot station to take it home.. I believe it only really failed the emissions because the tester put car with cats and closed loop control. .. it has no cats, its a j spec. Ill have to show him the mot guide I think.

 

Yeah your right about the £25 guys, there's a place near me that does it for £5... really just so they can buy a new Texas style hat.

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Well, I did fill it up with fresh before the mot, there was only about £5 of old fuel in there.. but would that £5 make the rest worthless is what im not sure about... or would that already have run through and finished? I got about half a tank left...

 

2nd edit...

forget about the first edit aha.

Edited by Tayfun.tugra (see edit history)
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