LC 100 TD VX 2001 suddenly gutless!

[RedbankRookie]

Hi all. having a problem with acceleration at low revs - really apparent on mild road inclines when cold. Been running fine then went out one day recently and from cold would hardly accelerate up a mild incline. Foot to the floor and it started to gather momentum (not really accelerate) but improved as revs picked up. Have replaced the fuel filter (no change) and recently had a new air filter. Have done some research and a gummed-up EGR and inlet manifold seemed to fit the symptoms but it can apparently be checked if you disable the EGR by disconnecting and closing the flexible pipe connection at the EGR. This I did with no noticeable change to acceleration so it doesn't look like the EGR? (but why would the EGR suddenly cause my problem in any case - surely this would likely be a gradual loss of performance as crud built up?). Could it be the turbo or a sensor, do you think? Folk lore suggests that if it is the turbo there should be loads of black smoke - there isn't - and there are no dash warning lights - no MIL. Also Once it gets up to speed it thunders along as previously. Any thoughts would be gratefully received.
Brian

Hey Brian,
I had similar problem with my 2001 VXJ95 Prado and others have also reported similar issues on this platform. There’s a thread somewhere started by AussieArthur sharing his frustrating odyssey with a similar-sounding problem. That’s where I ran across the following potential solution..

Remedy for my problem (& AA’s) was replacing MAF sensor which fixed the problem immediately and my 23 year old Prado now runs like new (has 318k on clock). Prior to replacing MAF sensor we’d cleaned injectors, replaced spark plugs and coils, replaced muffler none of which had resulted in any marked improvement.
Worth investigating whether your MAF sensor needs cleaning or replacing.
Good luck!

 

[bigone]

Hi Redbank,
Thanks for your insights but it seems that no MAF was fitted prior to MY 2002 - at least I don't have one at the base of the air cleaner where the Parts List shows that it should be fitted. Based on uHu's post earlier I have ordered a MiniVCI and TechStream S/W from ebay which should arrive next week - then I can have a chat with it!

 

[bigone]

So.....an update ! Purchased the lead and Techstream s/w from ebay and loaded it into my old XP laptop and connected to my Cruiser. This was all basically very straightforward. The s/w connected straight away and I ran the Healthcheck option (this shows all the stored DTCs across all the 9 ECUs). Result - no stored DTCs! So I have to conclude that what is monitored by the ECUs is working ok - so why do I have the problem in my original post? Logically, and on the assumption I do have a problem and it isn't just it's age, this can only be down to something that isn't monitored but that can cause the cold acceleration problem (it seems to me). It seems such a major problem that even if it's source wasn't monitored by an ECU then some other sensor would go out of range as a result and throw a DTC?
A question for uHu, please. The Vehicle Connection Wizard displayed:
Model Code: HDJ
Vehicle Spec: 1FT
(these are picked up automatically by the s/w)
Option 1: 'HDJ10' option selected (choice of this or HDJ7)
Option 2: '-0108' option selected ( I read this as all Cruisers up to Jan, 2008? There are other options of later dates but all they seem to do is increase the ECUs to 14, which are not found in the scan therefore no results come back).
Does this look right in case I am using the wrong input parameters? I was expecting the Vehicle Spec to be 1FTE (my engine)?
So at the moment I plan another monitoring session with the engine running (if there were no DTCs originally stored this will should a 'Nil' result anyway) and I am driving it with the diesel cleaner additive to see whether anything develops (so far no change). Anybody any other thoughts on how to progress a solution?
As an aside, I have to say that the lead/Techstream package is absolutely brilliant - thanks for the heads-up uHu! For just over £30 it covers more than a hand-held analyser and costs way less .
Brian

 

[uHu]

Haven't looked at TS for a long time now, but iirc you are supposed to get 1HD-FTE. And again iirc, it's the year first, so that -0108 means "up to august 2001 production".
And I suppose you have found that there is a difference between current DTCs and stored/historical DTCs.

 

[bigone]

Thanks for putting me straight on the year/month ! As to DTCs, Techstream shows none of the ECUs have any historic codes recorded - all clear. This is good news in one respect but doesn't help diagnose my problem, so it's back to the drawing board! If there were none stored then using Techstream while the engine is running is not likely show anything different, it seems to me.