Engine Light - actuator and wastegate seem ok - what next?

[daz_oram]

This is a new buy for me.  Not sure if I got a bargain or got a bucket!!!

When really accelerating hard over 40 mph or slowing increasing speed to over 65 mph the engine warning light comes on.  I have checked the actuator - the arm does move and have taken the waste gate off and it passes the blow test.  Sometimes it feels the orange light comes on as the automoatic gears shift up - sometimes feels like a bit of a 'stubbling'as these gears change on fast acceleration (but only  from about gear 2 upwards).

What should be the next thing I need to check?  Any tips?

Also....  if I choose just to ignore this problem - what is the long term consequences??

REALLY appreciate folks wisdom.

[ADarbon]

what year is the bus, It does sound like the turbo that is at fault.
What colour is the gear box oil. should be a nice cherry read if not it will need changing.
when you say it passed the blow test you mean you could not blow down the pipe
when was it last serviced air oil and fuel. if you dont know get them done. kernoman holds the sites filter stock.
what is the condition of the coolant.

[daz_oram]

The Estima is 1996.

In terms of the wategate - I took it off and did the blow test - no air going in.  The actuator lever arm wiggles nicely.

I will do a filter and gear box oil and engine oil change asap (next week!)

In terms of the turbo - if this is the problem - why would it work ok initially (e.g. zooming away from a standing start) but begin to faulter on the higher speeds?  Would it not mess up on all high revs?

[ADarbon]

With that description of symptoms. it sounds your problem may be fuel related.
First i would suggest getting a new fuel filter fill it with injector cleaner then take the bus for a long blast. if that don't clear it you'll need to check and clean the fuel tank filter.
Get this and the service done first and see how it goes, if no improvement then post and we can look more depth with the fuel pump and timing 

[daz_oram]

Changed the engine oil and fuel filter - filled with injection cleaner.  Took it for a blast and yellow light now comes on sooner.  To clean the tank filter - do i take the tank off / and I have read somewhere about a solenoid filter - do these have them on - how easy are they to get to.

Thanks

[daz_oram]

Just done a bit more reading.... I needed to mention that I did put some nice filtered WVO in the tank when I first go it.  I guess if the 'tea bag' (if it has one) is blocked this would be a cause of the problem!  Do you sell the Tea Bags yourself?  Could I use something else instead of the standard Tea Bag?

Having run many cars on WVO but completely new to these Toyotas I find that if this be indeed the problem - it shows itself in a strange manner.  I have had cars that were beginning to get blocked filters beginning to 'race' when idling, or stumbling on acceleration, or generally not having power.  This car seems to be OK until I reach a speed of [now] 50 mph and then the engine warning light comes on.  Perplexed.

[ADarbon]

Veg oil is very good at cleaning all the gunk out of the fuel tank so it is possible that the tea bag could be blocked
i cleaned mine and just put it back it i
if you want to order a new one go direct to toyota
theres a hatch under the passenger seat at the roller door i'll put a link to the thread for the job

[ADarbon]

https://estima-motoring.co.uk/Forum/index.php?topic=5187.msg67589#msg67589

[ADarbon]

https://estima-motoring.co.uk/Forum/index.php?topic=4293.msg57566#msg57566

[daz_oram]

Thanks for this.  Took out Tea Bag - suprisingly clean (but cleaned it anyway).  Took off tank - emptied out and refilled with diesel (the tank was also much cleaner than expected).  Took it for a spin - no real major change.  Started to change ATF.

systems are still;  orange light comes on at either 65 mph when accelerating slowly or about 45 when giving 'beans'.  Seem to be OK then a noticebale power loss or stumble before the light comes on.

What do you advise next?

Many thanks

Darren

[ADarbon]

does the pump at the top of the fuel filter housing stay hard when left for a while. If it goes soft then you have a air getting in the system. replace clips and check hoses.
Check the exhaust manifold for cracks loss of air hear causes loss of pressure.
Check pipe connections and clean the turbo inter cooler. its by the passenger front wheel you need to remove the covers to get to it. If this is seriously clogged it will stop the turbo from working properly.
Check your injector pips for cracks.
A question for you Is there any chance reason that your Timing could be out a notch because this would have the same effect.
Faulty EGR can cause problems when it fails but normally get black smoke (soot) from the exhaust when that happens but you could blank it off to rule it out

[daz_oram]

I think I have found the problem....  went out with a friend to add a fresh pair of eyes on the problem;  the actual issue seems to be the change from 3rd to 4th gear.  On fast acceleration it does not like changing up.  GUTTED!!!!  This sounds like a dreaded gear box issue!  From your wisdom and expereince - what do you suggest? 
Many thanks

[ADarbon]

Have you changed the gear box oil yet. if its in a really bad condition it can cause problems changing gears up to the point it won't drop in to overdrive. takes about 12ltrs to fully change it keep the old stuff because you can filter it and put in the fuel.
It could also be a problem with the ECU

[daz_oram]

will change the atf - following what you wrote on other pages.  How do we test ECU's to see if they are working ok?

[ADarbon]

only real way to tell if the ECU is at fault is to put one in you know works fine and test on that you can do a diagnostic check for faults ill add the link. I do remember a member from last year done loads of checks to find gear problems and was told he needed a new gear box. he was going to scrap and i said to change the ECU before he gave up and it worked.

Maybe I wont add i link I cant seem to find it. I think you cross T1 and TE put the ignition to position 1 and count the flashes