Thread: Throttle Response

Originally Posted by laughto

If the sensor was 'sticky' and the computer thought the brake was still depressed, wouldn't the brake light be illuminated?

My problem was when I took my foot off the brake and pressed the accelerator. The first time it happened I nearly required a change of underwear. I was a an intersection turning right across oncoming traffic with plenty of room until it just sat there for what seemed an eternity. The dealer simply adjusted the gap between the sensor and the brake or at least that's what they told me. Still have hesitation sometimes but I let the car roll a touch before I take off. I certainly would not cut across traffic with little room to spare.

Martin

Originally Posted by laughto

If the sensor was 'sticky' and the computer thought the brake was still depressed, wouldn't the brake light be illuminated?

I believe there are actually two switches in the brake switch. One for the lights and one that sends the signal to the computer to indicate the brake is pressed. The problem occurs when some carbon build up on the light circuit goes into the switch for the computer. It then sends a signal for a longer period of time to say that the brake is on. Its not until that signal clears tbat you suddenly get throttle response back. This may only take a second but when you want throttle at a roundabout it feels like ages.

Originally Posted by RoverLander

Its not until that signal clears tbat you suddenly get throttle response back. This may only take a second but when you want throttle at a roundabout it feels like ages.

I have this problem occurring more and more these days, and I have a switch sitting in my "in car spares" collection, which I think I may see about fitting today. The car is 175,000 km on the original switch, which is why the spare is always carried in the car.

Edit: Just did the swap - the old switch is the FoMoCo part, with the slightest blackening on one of the contacts, so cleaned it up, bent the contacts a touch and reassembled to throw in the spares with a "used" label on it.
I will see if the new switch has improved the throttle response from a standstill

Originally Posted by RoverLander

I believe there are actually two switches in the brake switch. One for the lights and one that sends the signal to the computer to indicate the brake is pressed. The problem occurs when some carbon build up on the light circuit goes into the switch for the computer. It then sends a signal for a longer period of time to say that the brake is on. Its not until that signal clears tbat you suddenly get throttle response back. This may only take a second but when you want throttle at a roundabout it feels like ages.

OK, so I thought about this for a while and was certain that I'd tried a left foot on brake/right foot on accelerator hill start way back when I got my first D4 in early 2010. I think the car went off pretty well. But I hadn't actually checked the revs.


So tried this today in my MY13 D4 and though and behold, left foot firmly on brake pedal and right foot on accelerator ...... the engine revs and the car tries to pull. The engine doesn't appear to be retarded at all.


Surely that debunks the brake switch theory?

Originally Posted by Celtoid

OK, so I thought about this for a while and was certain that I'd tried a left foot on brake/right foot on accelerator hill start way back when I got my first D4 in early 2010. I think the car went off pretty well. But I hadn't actually checked the revs.


So tried this today in my MY13 D4 and though and behold, left foot firmly on brake pedal and right foot on accelerator ...... the engine revs and the car tries to pull. The engine doesn't appear to be retarded at all.


Surely that debunks the brake switch theory?

Doing this will actually improve response as you get the turbo(s) spooling by adding load to the engine.

I know that so far, replacing the switch has not made a difference to my 3.0's launchability.... Sand mode on the other hand, is another story!

I do know though, with my other car (Saab 9-5) and previous Saab models, the ECU has a brake input so that if the brake is depressed, the boost is restricted to "Base Boost" - about 6psi. No idea why this is, except that it is a great tool to find out if the wastegate control solenoid is faulty.

Originally Posted by dalil

I did enquiry to superchips
Here is Peter James respond.

Thanks for your email about upgrading your Discovery 4.

We do alot of 3.0TDV6s as they respond so well to being Superchipped. You will get alot better throttle response, low down and midrange torque and the car will pull all the way to the red line. Many owners report anything up to 10% saving on fuel as well, due to the fact there is less gear changing. And the annoying lag that they have at low revs also disappears. With the Discovery 4 the gains are as follows;
LAND ROVER - DISCOVERY - DISCOVERY TDV6 - 3.0 - 210BHP - VERSION (1)
PERFORMANCE
Original HP: 210 (152kW) Original Nm: 520
Tuned HP: 260 Tuned Nm: 620
HP Increase: 50 (38kW) Nm Increase: 100
% Increase: 23% % Increase: 19%


All fittings come with a lifetime warranty and have a million dollar cover and we have never had a claim in 39 years. We are the official Mini Cooper, Audi and VW Rally team ECU reprogrammers in the UK and as such work closely with the manufacturers so we do not go over their recommended tolerances. As such, if you do not want to tell them it has been done, they will never know.

The upgrades takes about 3-4 hours to do and we come to you to do it. The price is AUD$1,349 fitted. If you'd like to go ahead let me know and I'll arrange a time. I will need somewhere to work, such as a garage with light, power and a bench or table, as we need to programme direct to the ECU. Ideally I'd start mid afternoon and be finished by about 7pm. We can also do an EGR delete for you at the same time. You need to blank the EGR off as near as possible to when we map it out as otherwise the engine may go into limp home mode. It shouldn't do, but there is a chance, so good idea to physically blank it off as well.
Please note this is not a plug in box. All they do is up the fuel line pressure. Now bearing in mind your vehicle is running about 15-20,000psi in the fuel lines, do you want anymore? We have seen over ten cases where the pressure has been so high that the injectors have bowled, so instead of being shaped like a V they have gone to a U shape, or burnt the tips out. Also some where the fuel has been forced past the rings and into the sump. Diesel in the engine oil is not a good look! We don't up the fuel rail pressure, we remap the ECU, so change the pulse, ie when it puts fuel in and for how long, the timing, throttle response and boost on the turbo. A remap is a more complete method of upping the power and does not put any extra strain on the fuel line.

Hope this helps and if you have any other queries, please feel free to get in touch. I will be in Melbourne the first week of May as I have some jobs booked to do there. I am in Adelaide on 29th April and then will be coming through on my way to Sydney and Brisbane. So happy to do it then if you wish.

All the best.

Peter James BSc.(Econ.) B.P.B.
Peter James Tuning Ltd, exclusive distributors for
Superchips & Bluefin in New Zealand & Australia
Mobile: +64 (0)27 2757574
Office: +64 (0) 800 89 CHIPS (24477)
Email: peter@superchips.co.nz
Web: ECU Remap | Chipping | Engine Tune | Peter James Tuning | Superchips
ECU Remap | Chipping | Engine Tune | Peter James Tuning | Superchips
Rediscover the joy of the open road


I think will go for it, but i am not sure if should i wait till warranty finish another six month.
Dali

"All fittings come with a lifetimewarranty and have a million dollar cover and we have never had a claim in 39years. We are the official Mini Cooper, Audi and VW Rally team ECUreprogrammers in the UK and as such work closely with the manufacturers so wedo not go over their recommended tolerances. As such, if you do not want totell them it has been done, they will never know."

I have no vested interest in this whatsoever but I have read this stuff before and Roo Systems have similar lines ....

Their quote....
“This goes even further than that. If you have an engine failure andthe manufacturer can prove it was caused by our products that’s on us as well.”

Firstly, just 'cause you support a rally team does not make an OEM approved specialist (especially if the cars were built in the 80s...LOL) ..... maybe abit of journalistic licence there.

It would also be interesting to analyse the T&Cs around the 'Million Dollar' cover claim.

Secondly, regarding "the OEM will never know" (Superchips) claim, inthis thread ....

http://www.aulro.com/afvb/d3-d4-rrs/230830-tdv6-sdv6-3-0l-power.html

... a few posts in, Tombie discusses how certain manipulation of the ECU creates an indelible record that can only be detected by the OEM's Diagnostic Tool. This comment was specific to re-mapping. This Mr Chips guy was asked about that by another party and stated that he knew nothing about it and had to check with his UK counterparts. His later reply was a tad defensive stating something about all Internet Experts being Experts, etc ... blah, blah, blah but admitted that his UK contacts had stated that it was partially true. He fluffed it off as him never seeing it here so it must be only 2016 models. Well of course he hadn't seen it .... that was the point of the other post!

So, taking the above into consideration, let's play devils advocate about thewarranty claims by these companies....

Scene 1


Owner walks into Land Rover with damaged engine/transmission/drivetrain andstates the above warranty claim from remapping company. Land Rover laugh.


They won’t make any effort to prove it. Why should they, the owner has let acompany that has 0.0001% of the R&D budget thatJ LR have modify his car? They might rightly state that RooSystem’s know their (RooSystems) gear but do not fully understand Land Rover products. Land Rover expressly warn about modifying without approval (Warranty becomes void).They state, get RooSystems to prove their kit didn’t cause the issue, you paid to get the car modified, not them.

Owner becomes piggy in the middle. So what does owner do?

That’s pretty much where it would end with the owner being out of pocket for an engine, driveline or transmission (or all) repair.

Scene 2

Owner has to decide who to sue and for what?

JLR (one of the most successful companies in the world) for? You can’t order them to ‘prove’ the RooDevice made their engine fail. You’d have to sue them for not covering the warranty, even though you completely ignored their clearly stated warnings.

Maybe the owner decides to go for the ‘softer’ target, even though they signed a piece of paper that states that the owner must get the OEM to prove that it wasa RooSystems issue.

Owner once again, stuck in the middle.

Scene 3


Probable Reality.

The warranty line is BS, but it’s solid enough to cover RooSystems/SuperChips/etal only. ‘’Proof’ is ambiguous and you’d never get JLR to budge. The only real proof is the fact that the owner modified the car and probably has no way of hiding that. If the owner choses to sue JLR for a failure to commit to warranty and they did actually ‘prove’ that RooSystems were at fault, I’d bet RooSystems would then counter the JLR claims, on the very point of proof. Once again you’d be in the middle and very, very, very much out of pocket. How much do you think this would cost you? I seriously doubt it would get that far.

People have been modifying cars from spec for a long time, some with issues and some without .... across the spectrum I'd imagine. With major/critical mods, I think it's fair to say you run a risk of losing your warranty when you do this. But if you are happy with that, the car is out of warranty or you think the risk of issue is low.... well then that's OK and that's why plenty of people do it.

I'm not challenging these guys ability to do what they say but I'm questioning their comments around the cover the owner is afforded should something go wrong.

Just food for thought.

Very wise words Celtoid brings me back down to reallity, driveline & warranty worth a lot more than extra power and economy at this stage. Still got 3 years warranty left

Originally Posted by aus86inch

Very wise words Celtoid brings me back down to reallity, driveline & warranty worth a lot more than extra power and economy at this stage. Still got 3 years warranty left

Thanks mate,


As I've stated, I can't really comment on the actual physical/mechanical risk, I just think folks should go into these things with their eyes wide open.


Some people are comfortable with that risk, but at least they have considered it.


Cheers.