Automatic Transmission

grandpa · Member

Automatic Transmission

rgren2 · Guru

Just an idea, have a look at your body mounts, at that age they are probably compressed and could be squeezing on something or stretching some wires when turning.

grandpa · Member

Thanks rgren2
Are we talking about the Body or Engine mounts? I will check it out.

rgren2 · Guru

Body mounts. Wouldnt do any harm to check engine and gearbox mounts.

PeterInSa · Guru

The other thing that is turning right, is the steering wheel, something may be earthing on the turn, although I cannot see how the trafficators or horn etc could force the vehicle into limp mode, but you may have other functions in the middle of the steering wheel cushion..

grandpa · Member

Thanks good idea, worth checking, although why would it have been so prevalent while water was in the fuse box ?
Grandpa

Cuppa · Guru

What an annoying & frustrating problem! You suggest that the incorrect mounting of the fuse box was 'factory', but surely the fact that a Toyota Coaster fitted with a Hino motor suggests there has been a fair bit of work done on this vehicle, making the incorrect mounting of the fuse box of uncertain origin? (Unless you owned the bus in stock form prior to the motor being swapped - in which case the water in the fuse box would likely have always been a problem).

Anyway water aside, the fact that limp mode occurs in such a specific set of circumstances (tight right turns) I think others are on the right track. Something touching, shorting, separating etc when the steering is turned hard right.

Has it always done it since you have had it?

Would limp mode occur if you were just idling the motor at home & turned the steering hard right?

It's one of those awful problems which is likely only found with a time consuming thorough & logical search , one thing at a time to exclude every possibility. Too many variable to go jumping at possibilities - that ends up just confusing, unless you strike lucky. It will be a moment of triumph when you find it!

Was anything to do with the steering changed or altered (by even the tiniest bit) when the engine was changed - maybe even just something fitted back to front for example?

-- Edited by Cuppa on Tuesday 31st of January 2023 01:35:15 PM

Craig1 · Guru

Check the horn button, or under the button. In a LC200 the disc can cause some weird issues if failing. Cant access lcool to get correct name for you.

Bicyclecamper · Guru

Well, I can tell you what can cause limp mode in a diesel engine: Mafs Sensor, Suction Control Valve, Turbo Solenoid, Injector pump, ECU, and head light sensor. I replaced all these in my 08 Pathfinder,and each time it fixed it, but in the end, it kept happening, so sold it to a wholesaler.

Southern Cruizer · Guru

grandpa wrote:
Hi,All
I have a very peculiarly Transmission problem with my Imported 2008 Coaster and I cant seem to get it fixed.
Vehicle Specification as follow:
Model: BDG-XZB51-ZRTQ4
Engine: Hino N04C-UB 4009 160 HP Turbo Inter cooled
Transmission: Aisin Automatic 6 speed, S/N SA-2407, (A860E/A861E)
History of Problems:
The Vehicle would run perfectly normal on long trips for hundreds of Km, however entering a Town and going into a roundabout (right turn only!) it would go immediately into limp mode, the only way to restore normal drive was to turn the ignition off and immediately restart the vehicle and it would be fine until the next sharp right hand turn.
I consulted several Auto Transmission repair shop with that problem but got so many conflicting solution and quotes from $ 400 to $ 6000 for a complete rebuild and other suggestions like remove the entire fuel system for cleaning, complete fuel injection service, on board Computer replacement and many other suggestions. One very helpful Specialist spend an hour investigating but could not find anything, in the end he gave up and to his credit did not charge anything for his effort.
I decided that once I get home I will check all the fuses and wiring myself, There are 3 fuse boxes the last one I checked was next to the front of to Vehicle batteries practically fully exposed to the element under the chassis, as I removed the cover of the fuse box water run all over my hand ! that to me immediately explained that water would have been splashed to the outside of the fuse box and effecting a particular fuse giving probably some conflicting info to the onboard computer?, I never had this problem before but then it did never rain as much as it did in the past few weeks!
After drying out the fuses and the box I took the Vehicle for a test run a docent times around a roundabout and as I expected there was no problems, I also discovered that the fuse box is factory installed up-side down! With the sealed lid at the bottom and the bottom with a slope to a drain hole on top! Also the cable entry was not sealed at all. After several other water entries into the box I relocated the box to the front of the Battery facing the offside with the lid now facing upwards and the drain holes on the bottom. This seem to fix the problem once and for all, thats what I thought, I just come back from a long trip (no rain) going up & down steep mountains no problems, drove into Town and now the problem is back again? But with a dry fuse box? Are there any sensors that my effect this situation ?
Has any one of you any suggestions how to attack this problem? Any help would be greatly appreciated.
Thanks Grandpa

Grandpa I draw to the conclusion from the 2nd last paragraph that the problem is pointing to the fact your vehicle doesn't like coming home

PeterInSa · Guru

Good One SC......

Mein · Senior Member

"Connect an OBD2 scanner and check for trouble codes. When the limp mode is activated, there is always a trouble code stored in the engine control module or the transmission control module. If you didn't find any trouble codes, try another diagnostic scanner."

PeterInSa · Guru

Re (When the limp mode is activated, there is always a trouble code stored in the engine control module or the transmission control module.)

Agree, But in some instances/vehicles the TC is deleted when the vehicle is restarted.

In the above instance, the strategy could be, have the scanner connected all the time, when into limp mode (at an Intersection?) make a note of the TC code for later fault finding.

This happened to a friend and the mechanic connected some electronic box that sent him ( mechanic) an SMS with the TC, when the problem happened

Steel Dog · Veteran Member

I once had a car where the exhaust was close the the engine mount and the heat unglued the rubber from the steel of the mount and when accelerating the engine would tilt and all sorts of things would happen, so when the engine power went down the the engine would settle back down on the engine mount and everything looked normal.

Jaahn · Guru

Mein wrote:
"Connect an OBD2 scanner and check for trouble codes. When the limp mode is activated, there is always a trouble code stored in the engine control module or the transmission control module. If you didn't find any trouble codes, try another diagnostic scanner."

Hi grandpa this is the answer for you. Now being an import it may not be as easy as some cars but if it has an electrical problem there should be some information in the ecu about the problem and probably history stored about things noted at the time. Even a cheap scanner will give some information but a better one should find more on a Toyota.

Even some of the normal Auto sales places will do a scan for you for a small fee, Supercheap, Repco, Auto 1 etc. Do not allow them to just clear the codes until all the information has been looked at and recorded.

If no codes are stored then my money is on a loose hanging wire, insulation worn through rubbing on some metal edge or loose connection somewhere. You could find that as easy as any mechanic can by spending your time looking carefully. Get a torch and a mat to lie on and look at all the wires and connections going to the engine and transmissions.

Good luck jaahn

-- Edited by Jaahn on Wednesday 1st of February 2023 06:32:36 PM

grandpa · Member

Thanks Gutu

The vehicle has not been modified in any way at all it is stock standard fully imported from Japan, the fuse box was upside down from the factory because the mounting braked and hole are part of the chassis and there was no other way to install it but upside down due to other equipment mounted above the box. as there are more than a dozen cables going in and fuses up to 80A I would not contemplate to lengthen the cable strand so I was only able to twist the box and bring it to the front of the batter(cables are very short!) You are right this will be a frustrating job I do mean that the water did play part of the problem, but what buggers me is hat it no also happen in dry condition it could that something is touching and sending a signal to the computer? I will just have to keep looking.thanks for your reply.

Grandpa

grandpa · Member

Hi Jaahan,

You are right it is very difficult to get any info from Toyota I wrote a letter to the Head Office in Japan. after a long wait I got a letter back from the Australian! Head office telling me point blank that they do not support any vehicle not purchased here and that was it . The last Mechanic tried 2 different OBD2 Scanners but found no reference to the Transmission but only a number of faults for the DPF but was unable to clear the memory he was baffled as this has never happen to him. Jet when you put a clean rag into the end of the exhaust pipe it is absolutely clean indicating that the filter is working correctly. I like the idea of driving with OBD2 to see what it does show, but have to find one first which works on my Vehicle.

Thanks Grandepa

grandpa · Member

Hi Steel Dog

Interesting, on a round Australia trip with my previous Landcruiser I had a similar problem, when all my fault light lighted up on the dashboard it frightened the hell out of me in the middle of nowhere. As the mechanical oil pressure gauge showed the correct pressure I was sure that nothing serous was happening, then noticed that this would repeat it self every time I left a Tank Station, i finally realized that with the extra Fuel weight (~80 Kg) the the Engine torque pulled the wire from the alternator! I extended the wires problem fixed.

Thanks Grandpa

Cuppa · Guru

grandpa wrote:

The vehicle has not been modified in any way at all it is stock standard fully imported from Japan,

---------------------------------------------------------------------------

So Toyota did produce Coasters fitted with the Hino Motor!

I must admit I am surprised, but it is so.

Jaahn · Guru

Cuppa wrote:
grandpa wrote:

The vehicle has not been modified in any way at all it is stock standard fully imported from Japan,
---------------------------------------------------------------------------
So Toyota did produce Coasters fitted with the Hino Motor!
I must admit I am surprised, but it is so.

Why surprised Hino is part of the Toyota group and has been for many years. The Coasters with the Hino motor are the pick of them. That motor would eat the old Toyota 6 that everyone thinks is king.

If there are no codes then it will be an intermittant contact of some sort IMHO as I suggested before.

jaahn

HINO MOTORS

https://www.hino-global.com

Introduction of HINO MOTORS Under the HINO brand, we represent the Toyota Group in the global market for heavy-duty trucks and buses.

Cuppa · Guru

Jaahn wrote:
Cuppa wrote:
grandpa wrote:

The vehicle has not been modified in any way at all it is stock standard fully imported from Japan,
---------------------------------------------------------------------------
So Toyota did produce Coasters fitted with the Hino Motor!
I must admit I am surprised, but it is so.
Why surprised Hino is part of the Toyota group and has been for many years. The Coasters with the Hino motor are the pick of them. That motor would eat the old Toyota 6 that everyone thinks is king.
If there are no codes then it will be an intermittant contact of some sort IMHO as I suggested before.
jaahn

HINO MOTORS
https://www.hino-global.com

Introduction of HINO MOTORS Under the HINO brand, we represent the Toyota Group in the global market for heavy-duty trucks and buses.

Surprised because I didn't know that was the case. Now I do.

deverall11 · Guru

grandpa wrote:
Hi Jaahan,
....... I like the idea of driving with OBD2 to see what it does show, but have to find one first which works on my Vehicle.
Thanks Grandepa

As much as I hate 'Apps', there could be an 'App' or some software that runs on a PC that could supply you

with data. For an LC200 there is a program call 'Techstream'.

gerlin · Member

Hi
Had a similar ( but NOT same ) problem with an automatic Camry 1992 ( may be before limp days )
Engine would cut out halfway along a left slip lane at traffic lights
Turned out to be switch on power steering that wasnt raising engine revs on no throttle
So once engine revs dropped load was too much when steering wheel turned and engine stalled
Very frustrating trying to get it diagnosed
Maybe if you can get someone to film it happening (showing dash instruments) you may help pinpoint the sequence of events

Good luck Gerry

Mein · Senior Member

1. Why are you linking the issue to the automatic transmission?

2. The mechanic would / should know that fault codes cannot be cleared if the problem is persisting. For example, the fault code for a misfire can be cleared if the engine is not misfiring when the OBDII is connected. But an ABS fault code (and I'm talking first hand experience here) cannot be cleared until the fault has been remedied.

3. Diesel Particulate Filters become faulty when they become (partially) clogged and therefore do not allow sufficient exhaust gas to flow through. It's not the case that DPFs allow soot to pass through when they become faulty. Therefore, a 'white rag' test is meaningless.

4. A faulty DPF is a common cause of a vehicle going into limp mode. The 'right hand turn' scenario may just be a Red Herring.

5. Until, and unless, you remedy the DPF fault code, you're going to be chasing your tail.

rgren2 · Guru

Mein wrote:
1. Why are you linking the issue to the automatic transmission?
2. The mechanic would / should know that fault codes cannot be cleared if the problem is persisting. For example, the fault code for a misfire can be cleared if the engine is not misfiring when the OBDII is connected. But an ABS fault code (and I'm talking first hand experience here) cannot be cleared until the fault has been remedied.
3. Diesel Particulate Filters become faulty when they become (partially) clogged and therefore do not allow sufficient exhaust gas to flow through. It's not the case that DPFs allow soot to pass through when they become faulty. Therefore, a 'white rag' test is meaningless.
4. A faulty DPF is a common cause of a vehicle going into limp mode. The 'right hand turn' scenario may just be a Red Herring.
5. Until, and unless, you remedy the DPF fault code, you're going to be chasing your tail.

Would a 2008 vehicle have a dpf filter?

deverall11 · Guru

rgren2 wrote:
...... Would a 2008 vehicle have a dpf filter?

Fourth generation (V80- / NS, NT, NW, NX; 2006) DPF standard fitment.

Mein · Senior Member

"Would a 2008 vehicle have a dpf filter?"

Possibly. I believe DPFs became mandatory in Europe in 2009 and some manufacturers started fitted them in 2008.

DPFs became mandatory in Australia in 2015 (but the Ford Territory never had one through to the model end in 2016). Some manufacturers produced single, worldwide models which were equipped with DPFs and some manufacturers produced two models; one for 'DPF' markets and one for 'non DPF' markets.

-- Edited by Mein on Sunday 5th of February 2023 10:49:29 PM

deverall11 · Guru

Mein wrote:
"Would a 2008 vehicle have a dpf filter?"
Possibly. I believe DPFs became mandatory in Europe in 2009 and some manufacturers started fitted them in 2008.
DPFs became mandatory in Australia in 2015 (but the Ford Territory never had one through to the model end in 2016). Some manufacturers produced single, worldwide models which were equipped with DPFs and some manufacturers produced two models; one for 'DPF' markets and one for 'non DPF' markets.

-- Edited by Mein on Sunday 5th of February 2023 10:49:29 PM