Runs with AFM unplugged.

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Dustin792
 

Posts: 19
Joined: Sat Dec 30, 2017 8:27 am

Runs with AFM unplugged.

Post by Dustin792 »

thanks for any help in advance.

In the beginning stages of getting my new build running. i am using a fairly base map, only changes that have been made are to injector size and the type of MAF sensor installed. Basically I am able to get the engine running with the MAF unplugged. Usually this is a sign the MAF is bad? but could it be the case I don't have something else done properly or is this just a bad MAF sensor? MAF was changed to Z32 VG30DETT 500hp in nistune.

Current setup
CA18DET
800cc Deatschwerks low impedence
Z32 MAF
3 Inch downpipe
high flow catalytic converter
Attachments
S13 CA18DET pete adams Z32 800.bin
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Matt
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Re: Runs with AFM unplugged.

Post by Matt »

Need the log file to see the MAF voltage

Plugged in should be about 0.4V and around 1.0-1.2V at idle

Most problems I see with MAFs are people wiring them wrong, or purchasing a counterfeit (fake) MAF from places like Ebay or getting one second hand in unknown condition.

Check with a multi meter that your MAF voltages increases when you blow through this (or blow through and get someone to watch the MAF voltage guage in Nistune)
Dustin792
 

Posts: 19
Joined: Sat Dec 30, 2017 8:27 am

Re: Runs with AFM unplugged.

Post by Dustin792 »

I did take a look at information regarding whether my MAF could be fake or not... I want to say i should be in the clear on that considering the actually metering portion inside the MAF has orange on it and the outside has the Nissan logo and serial number. Also the voltage was 0.450-0.460 and blowing into the sensor the volts did increase, so i guess its safe to say its a working sensor? I did get a [12] DTC AFM (starts=0) but i think that was because i had the MAF unplugged just to get it running. If that's the case the problem is still present and I'm still a bit lost. My current K constant is 172, Preignition time is 880.(reading into the math involved with Resizing the injectors and changing the MAF, with my vehicle and the upgrades i have shouldn't the load multiplier be much higher? This is a ROM with similar mods that was given to me BTW) I want to say my next move is playing with the load multiplier(k constant)? does raising it lower or raise the AFR?
gauges2.png
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Matt
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Re: Runs with AFM unplugged.

Post by Matt »

Good, you have done some homework on it. However if you took a similar tune and it doesn't work then there is another problem

I would suggest adjusting TIM until you get 14.7:1 (stoich) AFR on cruise @ 2000rpm (assuming you have feature pack [FP], otherwise adjust K constant)

Afterwards if you have FP then adjust K constant until load cursor stays within factory load scales and again adjust TIM for stoich cruise mixtures

Then see how the mixtures go from 14.7:1 to going on boost
Dustin792
 

Posts: 19
Joined: Sat Dec 30, 2017 8:27 am

Re: Runs with AFM unplugged.

Post by Dustin792 »

Thanks much for your help.

i am learning little by little here. so i have been able to get the vehicle to idle with the MAF plugged in without any codes using a similiar tune. Main differences i noticed with this tune is the K constant was higher (from 172 to 383) (not using the feature pack BTW) , also the crank enrichment tables were slightly different. Had it running for over 40 mins hoping the idle would subside but stayed at a hung around 1600 rpm, attempted to play with the idle control adjustment screw lowered it maybe 100 rpm. Although the idle is high its not rough and giving it some gas the powerband is fairly smoooth. AFR at 1600rpm bounced around at 13.8 to 16 but mainly in the mid 14's. Am i looking for 14.7 AFR at 2000 rpm cruise under load or not under load? If someone could take a look at my log file for some indicators as to why it may be idleing high or anything else you may see it would be much appreciated, in the meantime i will be trying to learn more about process itself, thanks again for any help.
NIStune_2018-02-01_1643_06.csv
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Matt
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Re: Runs with AFM unplugged.

Post by Matt »

Try and keep logs short and where the problem is. I don't have time to go through 40 minutes of log file

What I see anyway is that the TPS idle indicator is not going on. Check your TPS variable input sensor and TPS idle switches are working. Explains the high idle. Even when you rev the engine at 11:14.672 in the log, the TPS does not change. Fix this before proceeding
Dustin792
 

Posts: 19
Joined: Sat Dec 30, 2017 8:27 am

Re: Runs with AFM unplugged.

Post by Dustin792 »

great point! I'm seeing it now. I did set the TPS to around 0.48v prior to starting the car and I made sure when I opened the throttle the volts increased but I'm not sure of the exact WOT volts. I did some research and found some people tend to think you should have a TPS that coincides with your ECU model(is that even a thing? which TPS model works with these if I need to replace it?). Anyhow I will double check all the TPS readings. Also can you expand on which portion is the TPS variable input sensor and TPS idle switches(IAC and AAC or is this on the TPS switch itself)? Also is the TPS idle icon in nistune's consult gauges supposed to turn red or not? You have been very helpful, thanks again.
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Re: Runs with AFM unplugged.

Post by Matt »

I am not familiar with CA18DET TPS or wiring (I can assist with tuning but not your wiring/mechanical issues)

What I can tell you is there there is a signal line (normally shielded - ECU pin 38) and GND (sensor GND ECU pin 30) and 5V (ECU pin 48) lines. The TPS will swing signal input to 5V when throttle is pressed. I'm not seeing this in the log. You need to resolve so pin 38 goes to about 4V when you press the throttle

TPS switch : idle lines are pin 54 and WOT is pin 57. Yes TPS idle should light up red when throttle is released
Dustin792
 

Posts: 19
Joined: Sat Dec 30, 2017 8:27 am

Re: Runs with AFM unplugged.

Post by Dustin792 »

So I opened Nistune and used the consult gauge to check the TPS parameters, with the engine off and ignition switched to on I am getting the red light for "TPS idle" and when I use throttle it goes away. Also the TPS is 0.46 (closed) and 4.26 (WOT). With my current understanding I would say the TPS should be working fine, but that doesn't explain why it isn't populating data when throttle is open. weird. Wonder if the IAC or AAC could be the cause or maybe all three sensors need to be in sync somehow. Thinking i should just replace the TPS to at least rule out the possibility of it being intermittent or faulty. appreciate the help I will continue to research it further. thanks again
Dustin792
 

Posts: 19
Joined: Sat Dec 30, 2017 8:27 am

Re: Runs with AFM unplugged.

Post by Dustin792 »

Did a continuity test on my current TPS idle switch and found it was intermittent with throttle closed and no continuity WOT. Did the same thing on another used one I had laying around, this time I found continuity was constant with closed throttle and went away WOT. So this may explain the high idle hopefully. Just before I was about to test it the USB leads wires going to the ECU decided to unsolder themselves... Leaving for a while anyways so won't be able to test it out for three weeks.

I know this probably shouldn't be in this thread but since i will be gone for a while thinking about sending the ECU in for the feature pack upgrade. Is the 36F05 board capable of being upgraded?
Noticed it said 36F0F under ca18det type 1 on the nistune website. Would be sending from the United states via UPS or Fedex.
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Re: Runs with AFM unplugged.

Post by Matt »

yes it is. Answered via email
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