Surging at low speed - any ideas

[JoshF Advanced Member Find all posts View Profile Close JoshF]

not sure what 3rd party gadgets like Scanguages you have but if you have access to Torque on Android via bluetooth or EcuDataScan you can monitor items things like Fuel Rail pressure which will show if there is any drop in pressure that might be causing a problem.

Why those two over a scanguage, they log to a file including GPS coordinates and monitored values so you can include RPM or other like items. You can then use the data in a graph etc to see drops below the standard value at idle.

[TimA Member Find all posts View Profile Close TimA]

Hi All,

I have just got back from a trip to the Red Centre and quickly racked up 7000+ kms and have just had the 40k service. I reported the problem also occurred at 100-110 km/hr (I was fully loaded, roof rack, etc) and quite often it would surge/hesitate if I accelerated to maintain the speed limit in outback SA/NT (bugger doing 130 as the fuel ecomomy dives) especially into a head wind.
FYI I have a few mods done but no engine chipping which they have asked me about (twice).

There is a new ECU update which apparently fixes the problem as per TNF 52/12 which they applied. They showed me the actual problem description but would not let me have a copy. I did read it and the description perfectly matches my symptoms (at both the lower & higher speeds). Something to do with the fuel and turbo (I don't have a photographic memory and it ran to 2 pages). The update was released on 2nd July. The 30k service was done on 18th June.

Anyway, update applied and time will now tell.

Interesting that Si & Rae had an update applied which hasn't fixed the issue and the dates of their post (and update) would be very close to the release date I mentioned (no specifics mentioned in post).

Tim.

[Si & Rae Member Find all posts View Profile Close Si & Rae]

Tim,

We had our car serviced at the end of June so we might have just missed out on the ECU update that you are referring too. We had the update done to fix the 2400rpm issue but it just seemed to make the surging issue worse (or at least more noticeable). We have a new born so she has taken priority for the last month but the wife is going to try and drop the car in to get the Drivers door switch fixed (stops lights turning off automatically), so I might mention to them the TNF 52/12 and see if they can do it at the same time.

At least there is a TNF for the issue, but lets see if it actually works or not.

[Riv39 Advanced Member Find all posts View Profile Close Riv39]

Tim, keep us posted on the outcome....still don't understand why all the 150 D4D's don't exhibit this problem though.

[TimA Member Find all posts View Profile Close TimA]

Will keep you updated. The problem was much more apparent at the 100-110 km/hr speed and I was fully loaded with camping stuff. Hard for me to go that fast in city traffic and to be that heavy.

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

Mate of mine had a similar problem with a manual GX, recently fixed with a software update.

[Riv39 Advanced Member Find all posts View Profile Close Riv39]

Must admit I don't do more than abou 90km/hr towing my trailer as I don't take it out of the city so maybe it is load related.

[Foxy48 Member Find all posts View Profile Close Foxy48]

Guys, I'm not sure here .Mine is a 201004 build and I have noticed a surging especially taking off when under load . so much so I suspected the taco is faulty as it doesn't register a drop in revs ,It just stays the same but there is a definite surge .I even call out to the girl "come on get moving" I have had a tune done on the trans, it stop the drop off when accelerating especially around roundabouts but this other one is when in a straight line under load . I use Flash/Lube diesel in my fuel but that's all . Cheers Foxy

[TimA Member Find all posts View Profile Close TimA]

Foxy,

The symptoms in the TNF exactly matched what I was experienced.

Surging/hesitation at around 40 km/hr and typically as it was changing gears (auto) from 3rd to 4th. I tried to record this but it was intermittent. I was very easy on the right foot in this situation.

Surging/hesitation at 100-110 km/hr. This happened frequently on my last trip. I was away for 3 weeks and fully loaded. On the open highway, if i put the foot down to maintain highway speed (due to wind, incline, etc) it would hesitate. Like a fuel blockage or starvation. Thought it was around the stage the ECO light was due to come on.

The description in the TNF mentioned both these speeds.

Tim.

[the ferret Junior Member Find all posts View Profile Close the ferret]

Could the problem be the throttle position sensor??
Altho I'm not very up to date with the 150 series.
Cheers, the ferret.

[Foxy48 Member Find all posts View Profile Close Foxy48]

Hi Tim,Mate,I have booked my girl in for the TNF next Wednesday. I spoke to my Toyota service agent and he said my symptoms pretty well match what the TNF hopes to fix.So I will have to wait and see what happens. It seems normal driving doesn't show up the surging so much as does driving under load ie towing Cheers foxy

[GQTrav Lurker Find all posts View Profile Close GQTrav]

Mine would surge/hesitate at any speed atleast half a dozen time's a day under gentle acceleration, worse when I was towing a trailer load of firewood. I had the ECU update done at the 30k service and touch wood, it hasn't done it since.

[Kev7762 Senior Member Find all posts View Profile Close Kev7762]

Dobbo, your problem sounds like the 2400rpm flat spot issue. A software update is available for that, the update number is:

TNS63/11 Hesitation on downshift under acceleration

It was issued on 26/08/11

There is also a long thread on the topic located here http://www.pradopoint.com/showthread...0rpm+flat+spot

This is something I occasionally have as well, no chip so can't blame that, but occasionally seem to be able to confuse the transmission and it seems to hesitate like it is trying to decide to lug or down shift.
Will have to mention to Toyota at the 60k service.

[Foxy48 Member Find all posts View Profile Close Foxy48]

Kev, you have said what I tried to say .It is just as though the trans can't make up its mind ,I will be getting the tune on Wed next week so then it will be interesting Cheers Foxy

[TimA Member Find all posts View Profile Close TimA]

All,

I have had the new FW for a few weeks now and the problem hasn't surfaced. Although I haven't been fully loaded, I have been out on the open highway and done a few tracks. It hasn't even "felt" like it was going to happen. Previously I would "feel" it was going to occur (hard to explain but you just know) just before it happened. So far so good.

Tim.