Prado Hesitating..? Please Help!!

[brockbaker Lurker Find all posts View Profile Close brockbaker]

Firstly, sorry if I have posted this in the wrong section..

I recently purchased a 2011 Toyota Prado GXL D4D Manual with 180,000 on the clock.
I have searched for this issue through out the forum but couldn't find any directly related..

I recently purchased a Steinbauer unit from eBay and fitted it to my Prado with great results for the past couple of weeks.
Just the other day my wife started driving the car back to Brisbane and not long as she got onto the highway it started.. About 15 minutes into her journey the car started what she could only describe as a hesitation in the engine at times but could not replicate the problem on demand.. It seemed to do this a lot more as the car when from a cruise condition to an under load condition i.e. Going up a hill or overtaking.
After arriving at Gympie and spending the night, she said that this problem got even worse the next day as it started doing this "Hesitation" under normal driving conditions.
Because my wife wasn't far off driving through Nambour where Just Autos Mechanical is located, I figured this was the best place for my wife to drop though for a diagnosis. When my wife first arrived, the Prado continued to Hesitate when Just Autos took it for a test drive and I believe that they initially said that it come be a dirty fuel filter or bad fuel; but after inspection and injector test carrier out all was deemed clear.
After a quick look over the engine they also said that everything sounded and looked in very good condition.
The car's engine management light doesn't flag or nor is the any soft or hard fault codes registered on the ECU.
To start the fault finding process, they disconnected the Steinbauer and the hesitation has not happened again, but...
One of the reasons I believe that it may not be the Steinbauer causing this issue but maybe amplifying it; is because when I drove the car from Brisbane to Gladstone I felt something described very similar to what my wife explained to me but to a lesser degree as I didn't have the Steinbauer fitted at this stage..
I was looking at removing and sending the Steinbauer Unit to Diesel Care for piece of mind for a bench test and they also said they would run it in there Shop Car to see if they have a similar problem..
I use BP Ultimate Diesel in the car and have heard that in some isolated cases that Prados may not like this according to some Intertnet forums..

I did send the link..

Surging at low speeds -any ideas
http://www.pradopoint.com/showthread...-ideas%2Fpage3

To Just Auto yesterday morning but after read this themselves and contacting Toyota about the software updates, they believed that this wouldn't help my car.

Just to cover this off..
Is hesitation a common thing with Prados?
Is it bad to use BP Ultimate?
Has anyone felt something similar after fitting a Steinbauer Unit?

Any help would be greatly appreciated!!
Thank you in advance.

Brock

[AussieAndy Find all posts View Profile Close AussieAndy]

I use BP Ultimate only in both my work 1KD Hilux and my Prado, never had an issue with hesitation or any other fuel related problems. If it doesn't do it with the chip that's where I would be pointing my finger. Any concerns with the fuel system I would advise to replace both fuel filters, at least you know they aren't the problem then. It is a weird one though, did they get it to play up while viewing live data? What was the fuel pressure doing while the problem was there? Could also be a weird SCV thing.

[ozimacca Member Find all posts View Profile Close ozimacca]

I use BP Ultimate diesel in my 2015 GXL, no problems to report, I don't have a chip though.

[brockbaker Lurker Find all posts View Profile Close brockbaker]

Hey Andy and Macca, that's good news to hear about the BP Ultimate.
I don't think that they had a ScanTool connected to the car while it initially hesitated.. But I would be very interested in seeing the fuel pressures reading when it's happening, but now it's a matter of trying to replicate the problem on demand.. I have a ScanGauge II but I can't remember if it reads fuel pressure or not.. The main filter was replaced just recently and I purchased the under car filter but with work commitments I haven't had a chance to change it; but Just Autos said that they have checked the filters and they check out good. I would interested in watching the fuel pressure before I change the filters as to not do them if it's not needed..
Sorry but what's a SCV and would it throw a fault code?
Also as the car is not in my hands at present, I can't do fault finding myself which is killing me but I know it's in good hands with Just Autos. They just haven't experenced this problem before, but who knows, it could be by chance that the cars they have been working could of recieved that TNF 52/12 update??

[AussieAndy Find all posts View Profile Close AussieAndy]

SCV = Suction Control Valve it's what controls the fuel pressure. They won't throw a code if it's a minor issue with them, like sticking slightly every so often. It sounds similar to a Hilux I had at work a couple of years ago, except every so often his would stall but restart from key straight away. After doing lots of checks etc. and not finding anything it finally played up while we had the scan tool in and on live data. Saw fluctuating low fuel pressure, swapped out the SCV and no issues with it since.

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

Sounds very similar to a problem that I had that was fixed by an ECU update. Only used to happen at speed. I can't find the thread right now but is definitely somewhere on here.

Edit : found it http://www.pradopoint.com/showthread.php?28407-Help-with-D4D-intermittent-stutter-miss&highlight=Hesitation

[matt150 Avid PP Poster! Find all posts View Profile Close matt150]

Same problem with my car. Told Toyota to reflash it and fix it, 20min job and all fixed under warranty. Has NEVER happened again.

[Anth120playdo Banned Find all posts View Profile Close Anth120playdo]

I agree, it could be a Scv issue.

[brockbaker Lurker Find all posts View Profile Close brockbaker]

Sounds very similar to a problem that I had that was fixed by an ECU update. Only used to happen at speed. I can't find the thread right now but is definitely somewhere on here.

Edit : found it http://www.pradopoint.com/showthread...ght=Hesitation

Hey Krypro, I actually came across your Thread a little after I started mine and the Technical News Flash 52/12 sounded very similar to my issue. I forwarded that information to Just Autos and they took the Car down to Toyota with that flyer; they both agreed that it could be a solution so Toyota re-flashed my ECU. They reported back that the car hasn't hesitated since so I will be picking the car up tomorrow and fingers crossed it all behind us now.

Thanks for the Thread.

[brockbaker Lurker Find all posts View Profile Close brockbaker]

SCV = Suction Control Valve it's what controls the fuel pressure. They won't throw a code if it's a minor issue with them, like sticking slightly every so often. It sounds similar to a Hilux I had at work a couple of years ago, except every so often his would stall but restart from key straight away. After doing lots of checks etc. and not finding anything it finally played up while we had the scan tool in and on live data. Saw fluctuating low fuel pressure, swapped out the SCV and no issues with it since.

Thanks for the info Andy, if the re-flash doesn't do the trick I'll be watching my fuel pressure very closely..

[brockbaker Lurker Find all posts View Profile Close brockbaker]

I'll be sure to keep everyone posted as to how successful the TNF 52/12 flash turns out.

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

I run a Steinbauer and sports muffler with no problems so I would stick it back on.

[HiRAEdd Lurker Find all posts View Profile Close HiRAEdd]

Your post is basically word-for-word the same issue I had with my Prado. Have a look at my post:
http://www.pradopoint.com/showthread...ing-under-load

Short version is turned out to be a cracked spark plug.

Cheers,

Gavin

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

Your post is basically word-for-word the same issue I had with my Prado. Have a look at my post:
http://www.pradopoint.com/showthread...ing-under-load

Short version is turned out to be a cracked spark plug.

Cheers,

Gavin

Except his is a diesel, hopefully not running spark plugs because that would be a problem

[HiRAEdd Lurker Find all posts View Profile Close HiRAEdd]

Except his is a diesel, hopefully not running spark plugs because that would be a problem

Well, yeah, that is that

Honestly, I have no idea how diesels work but the symptoms are identical to what I was experiencing so maybe it might point to the "equivalent" area of the engine.