joeshaw123

Thanks for the info Adam. I tried adding and subtracting 5% then 10% of fuel and it made very little difference to running apart from the AFRs looking a bit off. It seemed to bog a little with +10% and felt a bit weak with -10%. I do mean to get a CAN lambda setup at some point but its analogue at the minute and staying that way, I'll probably go CAN lambda next year when I maybe look at e-throttle too. However - adusting the VVT cured it. I'm not sure I understand the mechanics of why cam advance improves torque and how you find the optimum values for a given rpm/tps%, but I went from 42 (do these max at 40 anyway?) down to 36 which massively improved it, then to 34 which stopped the issue altogether. I've not had the vvt tuned properly since fitting the 264s. Why would this happen, and why only in higher gear/higher load and not the lower gears? Is it just that you're spending longer in each load cell for the issue to show itself in the higher gears? Thanks again.

I seem to be having a weird misfire at high load pretty much WOT, low to mid rpm (2500ish), 4/5th gear only. 1-3rd pull fine from idle to the top end no issues. 4th OK when not loaded up but on an incline in 4th or any sort of road in 5th it seems to do this misfire/backfire almost full cut feeling thing. I'm trying to rule out any hardware issues before I take the car to be properly tuned, can anyone see anything untoward on my map? (only rough map I've been cruising around on to fault-find before mapping). If the map looks OKish, I'll have to look for issues with coils and wiring etc. I've changed plugs from BKR7E (0.9mm gap) to BKR8IEX 0.7mm gap, and the coils (VAG) are relatively new. No change at all. I've upped the dwell on vag coils from 1.8ms to 2.2-2.5ms with no change. I've attached the map i've been using while fault finding and most recent log with misfire like incidents at 1:04 and 1:16. Note i've not set knock gain levels at all so they read prettttty high across the board! Any thoughts at all appreciated, thanks. MARK II 2023-07-30.pclx PC Datalog - 2023-07-30 8;28;56 am.llgx Forgot to say it never did this before on the old hybrid setup but since then gone for 264 cams and G30-770 turbo. The turbo is on the smallest rear housing and I was worrying about compressor surge but don't think it would feel like this.

Thanks Adam. I was obviously misunderstanding the notes regarding the RS232 pinout in the manual but as far as I can tell, there is no pinout for the CAN 2 in the manual. Regarding setting this up for can lambda, is it as simple as connecting pins 2 and 3 to the correct pins on the CAN lambda; I don't need a terminating resistor or anything like that? And just change lambda 1 from whatever AN Volt I have it set to, to Link CAN? Cheers Joe

Hi I’m looking at getting a can lambda as my current analogue input is a bit weirdly temperamental (Stack gauge with 0-4v). I’ve been trying to get my head around the can wiring but for some reason I’m struggling. The JZX plugin manual refers to the Can comms as RS232-RX and -TX on pins 4 and 5, however the can connector CANJST seems to have the CAN on pins 2 and 3. In addition, I’ve been considering a Haltech Can lambda because of the considerable cost difference at least over here in the UK, among some anecdotal sensor life performance benefits, and they refer to it as Can-H and Can-L. Is the jzx link manual wrong or am I misinterpreting things - does CAN-H go to pin 2 and Can-L to pin 3 on the 5 pin JST? And the power and ground have to come from an external source on these 5 pin type ecus? Sorry for waffling on. Thanks in advance!

Hi, I personally run a G4X plugin but I'm trying to assist a friend in setting up his G4+ I'm trying to get the old manual to see pinouts and the like which I assume are largely the same but just want to be sure I'm using the correct information. The link on the website to the old G4+ manual just takes you to a G4X manual at a slightly different web address. Also I note that the G4+ doesn't have a JZXlink basemap - is this something that you have available? I've got one I found on an old post but suspect a couple of the analogue inputs are set up slightly wrong. Thanks.

Have you gone to coil on plug by any chance? Does your tacho work ok?

Thanks for the response Adam. I use one of the below sensors mounted in the charge pipe just pre throttlebody. Its a cast pipe so does have a bit more mass to it than a normal IC pipe, but shouldn't be too bad. However the mounting boss and pipe wall thickness mean the element/glass bulb bit don't protrude into the pipe very much at all so probably aren't reflecting the IAT very well when suffering from a bit of heat soak. It wasn't just lean on the restart but on a lot of low MAP, low throttle areas too. My fuel setup is bone stock minus an AEM 340 fuel pump + 730cc injectors so I don't think I'll have too much of an issue with fuel temps. Current IAT fuel trims look like the below: I've changed it to the below to pull less fuel out at low throttle. Also put smaller negatives for full throttle high IATs which hopefully I'll never see. Will hopefully be able to test it out soon but our weather has changed from 20deg ambient last weekend to 1deg and snowing today. Great. Thanks again.

Hi All, Took my car out on what was probably the first 20°C day of the year last weekend and had some issues with heat soak after a prolonged drive+parked up for half an hour then set off to go home. Idle was very lean, and low load/throttle situations were up at 16/17:1 AFR. As soon as it spluttered into positive pressure, AFRs quickly came down to a sensible number. Unfortunately didn't have my laptop to get any logs however I plugged it in when I got home and spied IATs close to 50°C despite ambient being around 16 at that point. I suspect a couple of issues: 1. My IAT sensor is a bit far out of the air flow; I'm inclined to get a longer, plastic bodied sensor so IATs are more realistic at low throttle situations. Thoughts? 2. My IAT Fuel correction table is only set up as 2D, with a linear ±2% fuel per 10°C of temperature difference. Why my mapper didn't add a load axis I don't know. So, I want to try a load axis so it doesn't pull fuel at low revs/part throttle but torn between TPS, MAP and RPM. Higher RPM, low throttle sitations aren't too bad, but trying to pootle around off boost results in a spluttery mess. Any input/advice greatly appreciated. Cheers.

Yes sorry I understand that. Regardless of which external pull-up I select, the temp doesn’t read correctly. It either reads full minimum (-10c) or full max (130c). I didn't change it during this run, but I have tried all of them with the engine running. I’ll do a log of a couple of different external pull-ups selected and see what happens. Can I possibly select an external pull-up that sees a reasonable range of voltages and map oil temp vs voltage instead of resistance, using the gauge as a guide? Or am I barking up the wrong tree here! I note that it sees pretty much the full 5v all the time. Does it calculate the voltage from resistance and external pull-up value, or resistance from the voltage and the external pull-up value? I did ask Stack for the value of the pull-up, and if it uses more than one pull-up throughout the range, but unfortunately they weren't able or were unwilling to provide the information. Thanks again.

I've attached the map and the log for a cold start and run for about 15 mins with a few blips of the throttle. Oil pressure is now working fine; I'd done the cal table wrong. Wideband isn't currently plugged in - I was hoping to resolve my oil temp issue before finishing the wiring. Any assisstance appreciated as usual! Thanks. Toyota Mark II.pclx PC Datalog - 2022-01-15 4;07;24 pm.zip

So I'm struggling a little to get the temp and pressure sensors working properly. I've wired them into ANTemp2 and ANVolt4. First, the temp - I've fed the signal into temp2 and it sees a voltage of course. I've used cal table 1 to plot resistance vs temp according to the values ive got (-10°C is around 64306ohms, log scale down to 309ohm at 130°C) but regardless of whichever external pullup I select, I can't get the value to read anything other than -10 or 130°. I've tried splicing the sensor ground into the ecu sensor ground but it made no difference. I don't actually know what the gauge's pullup is, or how to figure this out/measure it. I can't see any more than 2 decimal places on the AN volt value so its hard to know where to go from here really as I was thinking I could use V vs °C but no idea if that'd work. Pressure seems easy enough, and I've filled in the calibration table, but its a bit off according to the gauge (ecu reads low). I've not spliced the sensor ground in the gauge wiring into the ecu sensor ground - I wasn't sure whether this would be a good idea as I'll end up with the temp and pressure sensor grounds into the ecu sensor ground, then the wideband reference ground into the ecu sensor ground too. I figured I'd just use the analogue channels for the temp and pressure, and account for any voltage offset by changing the calibration for the temp/pressure sensors so they read approx what the gauge reads. I'd use both the 0-5v into anvolt5 and the reference ground from the wideband into the ecu sensor grounds, as the gauge has both of these and I thought AFR readings were pretty mission critical. Any input is greatly appreciated please!! Thanks. *sensor specs obtained from here: https://www.autometer.com/sensor_specs Temp sensor is 2252/P13125 Pressure sensor is 2246 (0-100PSI)

Couple of updates on this one for anyone reading in the future: Speedo on an aux output works fine, the VSS in the manual box goes straight to the white plug into the dash loom next to the ecu - you can chop it here and take the vss into the ecu on a DI pin, and send an aux out straight into the dash loom. Tacho works great on an aux out with a signal booster if you're not using the stock igniter, on VAG or R35 coils etc. I'll further update this with more info as I go.

It has a signal 0-5v and a signal ground so I'll make sure to use both. I think the AC has a large resistor on pin 16 to lower the high voltage tacho signal, according to this thread it does anyway: https://forums.linkecu.com/topic/11949-jzx100-g4x-plug-in-base-map/ So possibly if I use a signal booster straight out of the ECU, they'll both work (tacho and AC), or i'll have to modify both the clocks and AC control panel with something like a 1k resistor. Although I'm not rewiring the full bay, i've got most of the loom pulled back through into the cabin so I can get rid of lots of stuff I don't need; narrowband lambda, 3/5 maf wires, FPR VSV, diagnostic box and igniter, I'll just plumb it straight into the ecu! Thanks again.

Many thanks for the reply. I've got a couple of follow-ups if you can assist please I'd be very grateful. A pin which doesn't have a pullup? I thought I'd need to use one that does have a pullup for temp, and use one without a pullup for the pressure. I'm very much a novice when it comes to this so forgive me if im being stupid. Is AN Volt 4 suitable for a pressure sensor? I've double checked - the temp sensor is definitely a 2 wire so I assume this is a +5v feed then a signal return to the gauge, with no sensor ground. The pressure sensor has a feed, signal return and a sensor ground so I can try that grounded to the ecu sensor ground too. Noted, the gauge has its own built in wideband controller and provides a 0-5v output so that'll work ok. I suspect it may be similar to your MR2 (what year out of interest?) I don't really want to modify my clocks, I would rather use a signal booster of some kind. And from a quick look on this site and others it looks like I'll need to do so. From what I've read I probably also need to modify my HVAC unit so that it sees the rpm otherwise it won't let the AC clutch kick in. That's a bit down the line I guess! Finally - I assume I can just sort of reverse the way round it is wired; I believe currently the VSS goes straight to the clocks, then a feed comes into the ECU on DI7 from the clocks. I'm hopeful I can take the feed from the VSS and wire it straight into DI7, then an aux out back into where I cut the VSS feed. Probably. I'm certain I'll have more questions when it comes down to actually getting the thing running in a couple of weeks. Thanks.

I've seen a few threads asking similar questions and had half a mind to post in those, but thought I'd start my own - hope that's ok. My first query; I run Stack pro oil pressure, temp and wideband gauges so I already have sensors for those that have been working great for a year. I don't want to run more sensors than necessary so I wondered if I could splice off the returning signal from the temp sensor into AN Temp 2 and pressure to AN Volt 4 on expansion connector 1, and use cal tables to match what the gauges read. The sensors used are Autometer ST262252 fluid temp sensor (2 pin) and autometer ST262246 (3 pin, similar to Link's pressure sensor). Not sure if there's anything to do regarding sensor grounding - the sensors aren't grounded outside of the gauges. As for the wideband, that has a 0-5v output so I can just wire this into AN Volt 5... right? Second Q - I'm changing to a coil-on-plug setup using VAG/NGK U5002 coils. I'll likely stay wasted spark so I can use the ignition 4 and 5 aux outputs on the ecu for the speedo and tacho. Obviously the stock igniter will be in the bin and that usually runs the tacho. Is it as simple I take the green tacho wire that normally connects to the igniter and connect it straight to one of the aux outs on the ecu and set this as a tacho? Last Q - Can I take the gearbox VSS signal and route it into the ecu, and use an aux out to operate the speedo on the factory clocks? I assume this pinout is correct for JZX although wondered if it is digital input not another AN volt? Two reasons for this are my factory speedo is ridiculously incorrect, so I can , and rather pointlessly I want both the tacho and speedo to do a sweep on startup, because why not. Any and all advice greatly appreciated - thanks!