Anti-stall question...

[adzee]

I am sorry if this has been asked before but I use ForrumRunner and search is horrific!

Just wondering what year or model anti-stall was put in, and is it standard on all from what year?

I'm looking for a defender shortly, and want to know a bit more, how to activate/test it.

Thanks for your help.

[Larry]

It is only on the puma engine models - 2007 onwards & will only operate in low range.This happens automatically.;)

[adzee]

It is only on the puma engine models - 2007 onwards & will only operate in low range.This happens automatically.;)

Thought so! Looks like I won't be getting this then. :( I think...

Fingers crossed a good inexpensive one comes up. :)

[Cracka]

It actually works in high range as well, great for hill starts:)

[mools]

A late model TD5 has a type of anti stall. It's only on first low and it's not massively sophisticated, but if you let your foot off the cluth slowly and give no revs it will set off and fuel itself to tackle some half decent lumps and bumps.

[The Cone of Silence]

Definitely works in high as well as low range. I live on a hill and it's wonderful for parallel parking.

Bad for getting in a different vehicle though...I have to make sure I use the handbrake on hill starts!

[87County]

A late model TD5 has a type of anti stall. It's only on first low and it's not massively sophisticated, but if you let your foot off the cluth slowly and give no revs it will set off and fuel itself to tackle some half decent lumps and bumps.


.. just how a 1980s 4BD1 functions, except it seems to work in high range as well ! :D

[camel_landy]

Come on guys, get your facts correct! ;)

Anti-stall... A quick potted history.

In theory every single vehicle fitted with an electronic fuel injection system has 'Anti-Stall'.

TD5 has anti-stall but the parameters were tweaked and turned into a 'feature' for the TDCi (Puma) engined cars.

How does it work?

Simply, the ECU is constantly monitoring the engine speed and if the idle speed drops below approx 800rpm, it'll give it a little give it a little more throttle to get the engine speed back up. So, when you get the clutch up to the 'bite' point, the engine revs will naturally drop so the ECU (anti-stall) will compensate.

Anti-stall will work in any gear, Hi or Low range.

However, don't get confused with the "Idle Jack"... This increases the idle speed to 1000rpm when in 1st Low.

HTH

M

[mools]

Get your facts straight, buddy. :D.

I won't say correct because a fact is by definition correct. An incorrect fact is an oxymoron.


Simply, the ECU is constantly monitoring the engine speed and if the idle speed drops below approx 800rpm, it'll give it a little give it a little more throttle to get the engine speed back up. So, when you get the clutch up to the 'bite' point, the engine revs will naturally drop so the ECU (anti-stall) will compensate.

A td5 has idle revs of 750. The feature definitely only works on low 1st too. Idle in 1st low is at the same 759 rpm.

Ian.

[djam1]

Just got a new map from Jose for my TD5 the idle speed was raised up to 800RPM and changed fuelling.
Its fantastic not sure if it suppose to be a feature or not but in second high you can just let the clutch out without touching the throttle and it just idles off.
Very impressed

[mools]

Djan1,

This is off topic I Know. But since I disconnected the clutch switch from mine I can take off from idle in second (on flat to nearly flat ground). Before there was no chance. In fact disconnecting the clutch switch makes the vehicle so much better to drive on and off road it's quite remarkable. Seems I have been battling against it for years.

Ian.

[LoveB]

mools is that on a td5 or puma?

btw I read this....

http://www.defender2.net/forum/topic579.html

has anyone tried it on their tdci? apparently disconnecting does nothing. You have to short the two wires

[camel_landy]

Get your facts straight, buddy. :D.

I won't say correct because a fact is by definition correct. An incorrect fact is an oxymoron.

...SNIP...

A td5 has idle revs of 750. The feature definitely only works on low 1st too. Idle in 1st low is at the same 759 rpm.

Ian.
:D

I deliberately used the word 'Approx'... The TD5 & TDCi have different idle speeds and on top of that, the TDCi increases the idle speed in 1st low. :p

BTW - My favourite 'Oxymoron' is "US Military Intelligence". ;)

M

[ProjectDirector]

I was watching a YouTube video with Defender and cruiser 70 comparison. They made a point that the antistall feature actually gives the defender less control on steep downhill in low range causing it to run faster. Is this true? BTW am picking up my new 110 in 4 weeks.

Cheers

[LoveB]

I think it is. I've only ever taken james offroad once but I found myself having to step on the clutch at times to stop from going too fast.. but then i was in high. that might have had something to do with it lol

[Loubrey]

I was watching a YouTube video with Defender and cruiser 70 comparison. They made a point that the antistall feature actually gives the defender less control on steep downhill in low range causing it to run faster. Is this true? BTW am picking up my new 110 in 4 weeks.

Cheers

Can't say I've ever come across this... I've been down angles steep enough to need resting your weight on the steering with arms outstretched and I've never had it overrun.

The golden rules of steep down hills are:

Low Range Differential Locked (no compromise on this!)

1. No clutch
2. NO CLUTCH!!!
3. If in doubt step on the accelerator to regain traction and steering
4. Use the foot brake sparingly if you've lost your planned line...

The Puma's firsts low is so slow (when not interfered with clutch use!) that there is physically no way of not having control.

Any control loss would usually be attributed to the driver starting to panic and not trusting his car...

Cheers,

Lou

[camel_landy]

I was watching a YouTube video with Defender and cruiser 70 comparison. They made a point that the antistall feature actually gives the defender less control on steep downhill in low range causing it to run faster. Is this true? BTW am picking up my new 110 in 4 weeks.

Cheers

No, that's utter twaddle...

If the ECU detects the car is in Low-1st, the idle speed is deliberately raised to 1000rpm. This is called the 'Idle Jack' and nothing to do with 'Anti-Stall'. As stated before ALL EFi systems have an element of anti-stall...

The reason for this is that 1st-Low is soooo low, it actually increased the risk of the car sliding on a very steep slope. The idle speed is raised a touch, to help reduce this risk.

M

[Gerokent]

I have found on rocky ground some times the car won't go slow enough and it's "jerky". Would disabling the anti stall cure this?

[DEFENDERZOOK]

There are a few clips on YouTube showing what the anti stall is capable of......here's just one of them........

It works simply on revs....has nothing to do with what gear it's in on the td5.....or whether its in high or low range..........



► 1:45► 1:45
Land Rover Defender Towing a 12 Tonne Truck. - YouTube
Feb 2, 2009 - Uploaded by Timberpants
Defender's brochure tow spec is 3.5 tonnes. ... and fianally the truck applies its brakes - will ...

[ProjectDirector]

Can't say I've ever come across this... I've been down angles steep enough to need resting your weight on the steering with arms outstretched and I've never had it overrun.

The golden rules of steep down hills are:

Low Range Differential Locked (no compromise on this!)

1. No clutch
2. NO CLUTCH!!!
3. If in doubt step on the accelerator to regain traction and steering
4. Use the foot brake sparingly if you've lost your planned line...

The Puma's firsts low is so slow (when not interfered with clutch use!) that there is physically no way of not having control.

Any control loss would usually be attributed to the driver starting to panic and not trusting his car...

Cheers,

Lou

Agree all the way with you on all your points, all they were saying is that it didn't have enough engine compression to hold the vehicle steady. I will find the video tonight and post the link. Not sure if those guys were biased!

Cheers

[Naks]

The Puma's firsts low is so slow (when not interfered with clutch use!) that there is physically no way of not having control.

Not always Lou.

The Cape LR club did a trail recently where the exit goes through a steep downhill section with very loose & flat-ish small rocks. In that instance, 1st low was too slow, with the vehicles sliding as the rocks moved around. 2nd low was too fast. In the end we all did it 'hopping' 0.5m at a time

[mools]

It works simply on revs....has nothing to do with what gear it's in on the td5.....or whether its in high or low range..........

Ok, so on that basis mine won't stall when I try and set off in 5 th high then?

Betcha it will!

[Loubrey]

Not always Lou.

The Cape LR club did a trail recently where the exit goes through a steep downhill section with very loose & flat-ish small rocks. In that instance, 1st low was too slow, with the vehicles sliding as the rocks moved around. 2nd low was too fast. In the end we all did it 'hopping' 0.5m at a time

Hi Naks,

Yeh agree with you that surfaces differ drastically and you can't over generalise. Shale as you described it is nasty in most cases as they slide amongst themselves and take the wheels with them.

Works a treat though on most surfaces like clayey mud, sand and rocks. I climbed down a boulder spill (like a rock slide) up in Pilbara with boulders in the 300mm to 500mm range and the 90 just carefully stepped down them one at a time (did scrape the rock sliders acouple times though!).

BTW where were you guys? - My first 90 in 1996 was from Forsdicks in Bellville...

Cheers,

Lou

[Naks]

BTW where were you guys? - My first 90 in 1996 was from Forsdicks in Bellville...

Yeah, tricky stuff that shale!

We're in the Helderberg, currently in Gordon's Bay and moving to Stellenbosch in a couple of weeks. :)

[Loubrey]

I used to be a paid up member of the CLROC and LROCSA until I went to Central Africa in 1999.

I miss the Cape, especially when I see you photo posts! I had a place in Milnerton Ridge (Stable View:D), but most of my mates where from the northern suburbs through to Stellenbosch...

Cheers,

Lou

[ProjectDirector]

No, that's utter twaddle...

If the ECU detects the car is in Low-1st, the idle speed is deliberately raised to 1000rpm. This is called the 'Idle Jack' and nothing to do with 'Anti-Stall'. As stated before ALL EFi systems have an element of anti-stall...

The reason for this is that 1st-Low is soooo low, it actually increased the risk of the car sliding on a very steep slope. The idle speed is raised a touch, to help reduce this risk.

M

OK this is what I found and they describe this as the engine compression limitation
https://www.youtube.com/watch?v=PMhOhT5nwZk

Cheers

[DEFENDERZOOK]

Ok, so on that basis mine won't stall when I try and set off in 5 th high then?

Betcha it will!


If you ride the clutch long enough it will.......

[BilboBoggles]

OK this is what I found and they describe this as the engine compression limitation
https://www.youtube.com/watch?v=PMhOhT5nwZk

Cheers

I don't think that skipping down the hill was due to the idle RPM's, I think it's more to do with the open diffs, and the traction being lost. If you have open diffs and you lose the grip on one wheel of the axle - then you lose ALL engine breaking on that axle. But the LC with diff locks mean that you can lose traction in one wheel on one axle but the other wheel with grip will still have engine braking. Traction control won't work in this situation.

In my advanced driver training in the old Rangie we were taught a technique for driving throught the brakes on an automatic gearbox to increase traction, I think that might help in this situation as it would provide some braking to the wheels that still have traction.

[BilboBoggles]

Ok, so on that basis mine won't stall when I try and set off in 5 th high then?

Betcha it will!

There will be limits into how much fuel/power it can give the engine to keep the idle speed at the correct rpm. Given it's at idle you'd perhaps have 20% of max power even with it at maximum fueling, due to turbo boost etc not being there. So yes there will be limits into just how much power you can take from the engine at idle before it just stalls.

[mools]

If you ride the clutch long enough it will.......

burn out and cost a fortune to replace :D:D:D.

Anyway that would be using the clutch as an antistall which is somewhat irrelivent to the matter at hand. Face it, the antistall feature on a Td5 works only in 1st low when you take your foot off of the clutch without applying any revs. It does not work in all high and low gears as you previously stated.

If you still doubt me take yours to an incline and try it. ;)

[Yorkshire_Jon]

burn out and cost a fortune to replace :D:D:D.

Anyway that would be using the clutch as an antistall which is somewhat irrelivent to the matter at hand. Face it, the antistall feature on a Td5 works only in 1st low when you take your foot off of the clutch without applying any revs. It does not work in all high and low gears as you previously stated.

If you still doubt me take yours to an incline and try it. ;)

Ian is correct.

It staggers me how many people clearly do not know how to drive their vehicles correctly.

J

Sent using Forum Runner

[camel_landy]

OK this is what I found and they describe this as the engine compression limitation
https://www.youtube.com/watch?v=PMhOhT5nwZk

Cheers

No... That's not a limitation of compression, from what I could tell on that vid, that's actually a limitation of grip!!

What I think is happening there is when the axle is on full articulation, one of the wheels is starting to rotate backwards (thanks to the open diff) and it is effectively sliding. The other evidence to back that up is the dust it kicks up in front of the wheels... If it was picking up speed, without sliding, that wouldn't happen.

As the Toyota has its diffs locked, it isn't getting that.

M

[camel_landy]

Anyway that would be using the clutch as an antistall which is somewhat irrelivent to the matter at hand. Face it, the antistall feature on a Td5 works only in 1st low when you take your foot off of the clutch without applying any revs. It does not work in all high and low gears as you previously stated.

Nah...

Like I said, anti-stall is just a marketing term given to the feedback loop on an EFi system. Therefore 'anti-stall' is available in ALL gears...

...it's just that the TDCi works to different parameters.

However, whether the gear/terrain you're on lets you exploit that 'feature' is another matter! ;)

M

[camel_landy]

I have found on rocky ground some times the car won't go slow enough and it's "jerky". Would disabling the anti stall cure this?

No...

...and you can't 'disable' it anyway (read previous comments about it being part of ALL EFi systems).

However, what might work for you is feathering the brake.

M