Commsman

Saw a white M35 with sunroofs in Byron Bay this morning (S**-**1). Probably on holidays. Anyone on here?

You lucky bugger ! I hope you spot some really unique examples. Please get some pics if youy can

Ahhh.. see I was concentrating on the WOT 80% instead of the low down restriction. This will be much easier to test & now that my wideband sensor has arrived I will get back into it soon. This is an interesting thread and I hope something worthwhile eventuates with the ECU reflash.

DNS fail at who's end? Link works fine for me.

I think you are spot on and there may well be a couple of other parameters thrown in for good measure! If I had to determine exactly what the ECU looked at to open the throttle a given amount, I'd need a lookup table far bigger & complex than I'd be able to put together myself with the resources I have. I'm guessing now, but at this early stage I think I'd be lucky to get maybe an extra 10% total opening consistently. Another few % may come with the other parameters that will be outside of my control. I'll just sneak up on it tho. I little research, a bit of measuring, a LOT of trial & error & see what eventuates. And no, I don't particularly love DBW .

Discussion on the oil that one uses almost always ends in tears . People get very opininated about type & frequency of service so I'm not saying anything. However, Aaron, if your oil comes out looking like new you must change it too often . That Gulf Weestern stuff is good tho.

The date is locked in Eddie. Thanks. Come on everyone, we need people to be there or else Darrin promised the fmic was going to me!

I agree Ryan. The one with the lights showing is the money shot for me. Is your car really that clean Chris or did you photoshop out the stone chips etc? I don't reckon mine would've looked that good when it rolled out of the factory.

That looks great Luke. Look like big wheels too. She would have to be happy with that! Could end up like me and 'steal' the M35 away from the missus Welcome to the forum as well.

It's funny how nothing seems easy on the M35. Maybe we should be all driving C34's . I'm now considering this a challenge and will pursue it to it's completion, be it successful or not. With knowledge comes (power?) the ability to find solutions to other needs/wants/problems that may crop up in the future, plus I love to learn. It has also occured to me that if I have the ability to open the throttle a little more at say 20% (where I sit most of the time on the freeway) it will make the engine more efficient. If, as a byproduct of this, it reduces the injector pulse width with no or little change to cam timing I could have a sweet spot set up for a lean cruise mode. The point being, even if I'm not 100% successful in beating the throttle restriction above 80%, there could be an indirect benefit of this R & D work. I like the way you think -outside the box. I'm not sure if that is a viable solution but I will ponder the implications & anything else related that comes to mind during the week. It seems that almost everything in our factory ECUs are tied to something else. Thanks for your input Steve. Oh, and max throttle I've ever experienced according to the informeter is 85% I think. In the last couple of weeks it's been nothing over 80%. Again, it's so many other factors which determine what the ECU allows you to do. As for you other guys - you crack me up It doesn't take long to degrade into a free-for-all lol.

Thanks for your reply Scotty. I knew you would have at least thought of this before since I knew you'd tried with a cable throttle. So far every time there was an issue I lost throttle, ie no power, never the other way around. But it is a valid point & I was always careful with my testing done on, erm, the local test track in controlled conditions. I too think (now) a remap would be the best option if you desperately wanted the restriction removed, but I may do a bit more testing after my wideband arrives, just to satisfy myself - one way or another- that it can/can't be done this way. Even if I do get it working properly, I may still remove it because at the end of the day there's probably easier/safer ways to make those last few kW. It was a bit of a challenge & a sort of fun way to spend a weekend. I'll let others know what eventuates when I get time to have another play.

Sussing it out – The good, the bad, the ugly. Now it occurred to me that some of what was experienced could be attributed to the colder night air (12 deg C) & I’d also noted that the injector pulse width was mysteriously lower than expected for going so hard. Was the car running lean & that was producing the extra power? It makes sense when you think about it. The ECU thinks the throttle is only open (say) 60% when it is actually open (say) 80% and so only fuels the engine for that amount. Now I’ve never experienced firsthand how much gain can be seen by leaning off the AFR, but surely I had done more than inadvertently changed the mixtures? Mmm, my stuttering problem from before was probably fuel cut because of changes being too high. Lean out perhaps? I’m not sure. All this info was churning through my head overnight, but I decided that I had a win nonetheless. This morning, basking in the awesomeness of my success, I tidied up the wiring and mounted the interceptors either side on the ECU (double sided tape & Velcro) & did a few other things in preparation for upcoming mods. A short test drive this afternoon revealed the same problem as before. Temperature was now 10 deg warmer than last night. What to do? Lower the max voltage change & test again or reset all figures to zero. I decided I needed my wideband meter installed (on order) before playing anymore so I reset everything to zero before leaving to drive to Gold Coast airport (about 45 mins away). Now another problem had surfaced that wasn’t evident yesterday. Most noticeable at a steady cruise on the highway, I was getting slight variations in throttle openings, evident by slight “hesitations” as I drove along. Could this be because the interceptors were taking too long to route the signal through their electronics? I checked & it is <10ms from input to output so unlikely. Maybe more likely is because this morning I wired up ignition power from a source near the ECU that wasn’t as heavy gauge as the Acc power I used during previous testing. I must change this & test again. So when nearly at Tweed Heads, the car starts to drop the throttle altogether for a few seconds before giving it back. Crap! Then it throws up a MIL & I’m down to idle power, ie no accelerator at all. I pulled into an exit & removed the fuse to the interceptors so the inbuilt relay would pass the signal straight through. All back to standard & no more problems on the way home. The MIL even went out when I started the car . Where to from here? I’ll keep on reporting on what I find & if anyone is interested enough to offer suggestions I’ll do my best to try them out. For now my head hurts. Cheers, Leon.

Testing We started by adding/subtracting 20 units (not sure exactly how this corresponds to voltage) ramping gradually up from 1 – 20 from the load point representing 60% throttle opening & went for a drive. We also monitored the voltage at the throttle body before realising this won’t tell us much anymore. What I should have done (& will do soon) is measure the voltage on the wire that is used by the ECU to actually open the throttle. This will provide some critical information I’m sure. Anyway, at these settings there was no discernible difference. I did notice that when driving up a very steep hill it was impossible to get above 50% opening anyway. There are obviously other factors at play besides how far you put your foot down. All further testing was done on flatter roads after that. Next we tried adding/subtracting 60 units (maybe that equalled 0.6V which would put us close to maximum opening (total 4.6V instead of 4.0V) I thought. We also started ramping up the changes from the load point which corresponded to the 50% mark of the unmodified system. That should be easier to test. I stopped the changes at the load point where it maxed out in the setup phase. So how did this drive. Well, it went pretty hard but there was a couple of stutters and the figures in the hand controller where jumping around a lot. A head scratch later & maybe it was because the car had “dropped off” the edge of my ramped up/down settings. We then added figures up to 65 units of change & then continued the 65 figures all the way to the end of the range. So what we were trying was changing the voltages slowly (both up and down) from after 50% opening till about the old 80% opening and then holding that maximum change beyond that. What did it drive like? Absolute rubbish! The stuttering was really bad, even at low speed and moderate pedal depression. Obviously the car didn’t like that all. Still too high? Let’s leave the starting position at 50% (it drives as standard below that) and only ramp up/down to 55 units, continuing that right through to the end of the range. Still rubbish. Bugger. Beaten for now, we go home to forget about it for a few hours. Later last night I decided to give it another go. I dropped the max change to +/- 45 units, continuing the 45 settings all the way to the last load point on each interceptor. What did it drive like? Unbelievable! It was a whole new level of performance for my car.

Physical Setup It's not a very elegant approach, but I used two voltage modifier kits from Jaycar. I already had one kit & the hand controller made up since Christmas, so all I needed was another. I wasn't keen to spend heaps of coin on what was essentially a whim. These were installed in series with the two wires coming from the sensors (wires cut at ECU) so that the signal passed through them on the way to the ECU. I went for a few drives, with my son Jacob watching the hand controller & writing down the load points which corresponded with the 20%, 30% .... 70% & 80% throttle opening displayed on the Greddy unit. This was done for both sensors. When I graphed the results they looked exactly like the picture in the manual, funnily enough. By subtracting voltage from the red wire (rising voltage sensor) and adding voltage to the black wire (falling voltage sensor) I hoped the ECU would think that the throttle wasn't open as far as it should be and open it more.

Preliminary investigation. It started with me probing the most likely wire on the throttle body (red/white stripe/silver dashes) & found a voltage varying from low to high with more pedal depression. At warm idle it was about 0.65V and it increased by ~1V for each 20% throttle opening, as compared with my Greddy Informeter. The max I saw during testing was 4.04V which equated to 80% opening. So if you assumed that all I needed to do was intercept this signal & increase the voltage to open the throttle more (like I initially hoped), then you'd be wrong the same as me! I also probed a second wire (black / silver dashes) that had a voltage that varied from high to low. It was about 4.6V at idle going down to 1V at 80% throttle. Essentially these to signals are the inverse of each other. These two wires are the sensor wires that tell the ECU what's happening with the throttle. The Infiniti G35 has the same setup (although the voltages are slightly different) & this is the description from the manual. The throttle position sensor has the two sensors. These sensors are a kind of potentiometer which transform the throttle valve position into output voltage, and emit the voltage signal to the ECM. In addition, these sensors detect the opening and closing speed of the throttle valve and feed the voltage signals to the ECM. The ECM judges the current opening angle of the throttle valve from these signals and the ECM controls the throttle control motor to make the throttle valve opening angle properly in response to driving condition. I thought about modifying the signal from the ECU that actually opens the throttle, but the ECU would know straight away something was wrong via the feedback from these two sensor wires. So instead I decided to try to modifying the signal going to the ECU from the throttle position sensors.

I've been thinking about the M35 throttle restriction for the last few weeks & reckoned it would be worth some effort to see if I could bypass it in some way. I mean, how hard could it be? Last night I was convinced I had cracked it with a drive in a car that felt transformed . But as of this afternoon I'm not so sure . All sorts of gremlins have crept in to cause me a big headache so I've decided that rather than announce how I've found the Holy Grail, I'm going to turn it over to the community to see if we can solve it with a collaborative effort. That is if anyone is interested.... I need to do a lot more testing & gather more data to call this either worthy of pursuing or a total waste of time (don't stop investigating the G-Zone ECU flash quite yet) Please don't flame me. I am but a simple man having a 'bit of a go' to try to further the cause.

Yeah, that might prove to be a good idea. I'll get back to you if I need it. Thanks.

What EMU? It's more like a kangaroo lol. I think I've been misunderstood somewhere along the line. I've only got the stock ECU & no Emanage. In fact all my testing is done on a stock car except for a turbo back 3" exhaust. I was trying to beat the throttle restriction via a DIY "backyard" mod and I thought I had it beat last night after a cracking drive. But this afternoon when I took it out again I had gremlins in the system. So now I'm not convinced. As you may appreciate, I've been thinking, measuring, researching etc this for some time & so when I come to write up my findings it's taking me a while to type it out. Since I don't have a magic fix for everyone right now (like I thought i did last nite & this morning), I've decided to throw it open to others for their input & I'm happy to do more R & D and testing. I'll be starting a new thread a bit later (tonite I hope) with all relevant info & we will see how it progresses. Cheers.

Sorry for the delay guys. I've been really busy making the most of a weekend dedicated to modding & testing (missus is away so I can play ) I'll do a detailed write up tonight of what I've been up to over the last few weeks re the throttle restriction removal. I did a run last night that was just amazing. It was like a whole new level of performance. But like many things, there are some drawbacks with fooling the ECU. I'm going to restore mine to normal until I get my wideband sensor installed so I can monitor mixtures properly. You guys already running Emanage are going to love this! Cheers, Leon.

Been busy the last week or so doing stuff on the M35. This is the list of recent changes: Scotty's dump pipe Blitz NUR Touring cat back exhaust (quieter than original on the road, deeper not at idle. Very high WAF - impressed.) Custom 3 inch front pipe with high flow cat (made exhaust slightly louder across the rev & load range so now just louder than stock but still a high WAF). Will have to post the before and after vids. Removed throttle restriction Classed up the interior with some well placed LED lighting

Mine is called C1 (equivalent to your Cont1) but AFAIK they are both the same, regardless of what they're called. My relay is a big one (40A) so maybe it reacts a little slower than yours. I did have to be pretty quick on the gear lever though.

Sounds great. I hope it's not too far north... Was a decent drive last time. barring anything unforseen I'll be there. Cheers, Leon.

I see what you're saying. I never noticed because my default is with TV on. Just went & checked on my M35. With the screen on the trip meter screen, moving thru reverse puts earth on C1 and brings up camera as it should. Then when moving out of reverse it stays on the TV screen & plays live tv as you said. If I wanted the fuel consumption screen I would have to push a few buttons. I see your point. BUT, if I move the gear selection lever "briskly" past reverse the screen will stay where it was. That could be your answer.....?

Did you want a factory boost sensor Iain or did you get one from the wreck?

Thanks for that. Look forward to some (good?) news later.