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Link GTR

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try to log your TPS values (with a higher frequency) and accel enrichment. Maybe your inconsistency is coming from a fluctuating TPS signal and the ECU is constantly acceling and deceling.

Thank you KGPerformance , yeah I will be looking into it the next few days , just have some personal stuff to do . Wanted although to ask as I am watching the webinar 086/closed loop fuel control will it be possible to use this function and do the according adjustments in the set up section ? Would it be possible to use 1 wideband before the cat and send that signal ?

Disclaimer , I am not saying that I will not find the issue but if it was only an issue of 2 to 3% and not the figures that I see and all the components are ok , is this a way to get around a car that is pretty much ok but has a small percentage of fluctuation ?

Yes you can use closed loop fuel control to account for small changes in AFR. This is suitable if you're seeing fluctuations of 2% or thereabouts, however from what you're describing there is a more serious underlying issue that you need to look for.

So I did a few small tests again with the run values and data log and everything seem to be ok in terms of numbers that I am seeing being the same . I wanted to ask although the following cause I think its wiring issue . I unplugged the tps sensor and the black plug although can accept 3 pins (wires) but it only has 2 (1 5V and 1 signal) . On the tps it self it has another plug which also has 3 internal pins but it indeed has 3 wires going to it . Does that sound right ? Shouldn't the black plug also have 3 pins inside (like other vehicles) ?

Also I connected the mac boost solenoid directly to AUX 8 pin out according to the ECU and when I did a test the run times weren't showing me anything . It wasn't even going from off to on .

There are 2 different tps used by nissan at that time so the two plugs are for each type.

I'd you've wired on to AUX8 you can test it by switching it to 'test pwm' which will pulse the solenoid

If I remember correctly the 2 pin on the RB26 is just a throttle switch.

I cant remember what purpose it served but I left it out when I wired in my Link and used the wires to feed something else from the ECU.

The 3 wire connector is your 0-5v thottle position sensor.

Sorry guys for not getting back to you . I was running with some medical issues . So since health wise I am well again though to give an update to this headache of a car . So various wires weren't connected correctly having to fix part of the loom , the engine was out of timing ( my bad cause I did a compression test on the engine and it had the same reading on all 6 ) but trusted the owner that the previous technician did a proper job . Found as well some vacuum lines that weren't easily accessible no being connected and to be leaking and so on . I do accept most of the responsibility as I listened to the owner and didn't step my foot down insisting on doing what I ended up doing , regardless that I told him from starters I shouldn't had continued .

So I took the car on a quick road tune to verify that indeed I am ok now and I am very minimum changes which I will address through the closed loop control cause they are really minimum .

I wanted to ask although the only area that I am having an issue to have a good steady ratio is on idle . There are times that I pull aside and wait and my idle will go 0.8 with 49ms and then drop it to 47ms to go 0.95 and then after a few runs pull over and let the car idle the idle mixture is 1.050 and have to go to 49ms . I leave the car running and have that inconsistency . Any ideas ?

try logging your IAT compensations, the OE IAT sensor suffers badly from heat soak and could be causing this

Thank you Chris , quick question in the webinars it is stated that we usually set the same load axis on the ignition and the fuel tables but on this car due to the itb's we use fuel table the tps as load and on the ignition we map . Should the iat load axis also be with map or tps setting ?