More TPS & IACV Quirky Conditions

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husseinholland
Posts: 122
Joined: Wed Sep 12, 2018 2:44 am

More TPS & IACV Quirky Conditions

Post by husseinholland »

I'm using an '05 RSX (PND) ECU, JDM TSX harness, with the DBW TB (App Sensor) rewired for TPS & IACV, with the appropriate wires moved in the "A" connector for TPS power, signal and signal ground (A20 A29, A23), and IACV signal (A12). I have confirmed the wiring from the ECU to the connectors multiple times, the signals are all correct, just backwards (1 power & 3 ground) at the IACV connector.

What I meant by the title was that with the IACV re-wired according the diagrams - 1= (-) 2= (vBat) 3= (A12)

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....the system is not recognizing the throttle change and goes full lean off idle. I can see in the logging window that the TP % is not changing. I reversed the IACV 1 & 3 wires back to the way I had them previously, and got normal throttle response back, TP % sweeps when throttle depressed, engine responds.

It's just weird. I also realized today that based on the factory wiring diagrams, my TPS was also reversed 3 (A23) 2 (A29) 1 (A20) (L-R), but when I rewired it 1 (A20) 2 (A29) 3 (A23) as indicated in all the schematics,

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the throttle angle reads in reverse in K-Tuner, and I got P0122 error codes, so I put it back as it was. I see that in the diagnostic testing the K20Z1 uses the opposite wires (step 9, pg 11-125 RSX manual), so the TPS can clearly be wired either way, depending on application.

What I don't understand is how or why having the IACV wired correctly would cause the throttle angle to not be recognized.

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With it wired 3 2 1 it registers 0 closed throttle - 65% WOT (gas pedal pushed to the floor, I'm assuming that is another issue I will need to address). I could find any evidence of a setting where you can alter which way the TP signal goes. I don't understand why it would register backwards in K-Tuner when wired as per factory diagrams

Is there something I'm missing?

Bottom line is -

1) with IACV wired per diagrams, TP angle is not registered in K-Tuner & engine goes full lean off idle, cannot be driven.

2) With TPS wired as per diagrams, TP angle registers in reverse in K-Tuner layout window.

Thoughts or suggestions?
husseinholland
Posts: 122
Joined: Wed Sep 12, 2018 2:44 am

Re: More TPS & IACV Quirky Conditions

Post by husseinholland »

To wrap this up, I ordered & received a new Honda-packaged IACV today.

Plugged it in, and rechecked all the diagnostic values. This time, I got vBat between A12 & ground ("A" connector unplugged, key on).

Installed it, and ran the engine. Now it acts as one would expect, idle is elevated when cold, drops as energy heats up. Throttle response is as it should be.

So, bizarre as it is, the problems with back feeding, TPS response were all caused by defective IACV.

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Just have to tidy up the wiring

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KTuner
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Re: More TPS & IACV Quirky Conditions

Post by KTuner »

That is definitely an odd one. Glad you got it worked out!
husseinholland
Posts: 122
Joined: Wed Sep 12, 2018 2:44 am

Re: More TPS & IACV Quirky Conditions

Post by husseinholland »

To continue with this - The jerky throttle on tip-in or when cruising with little or no throttle came back. I have switched to a 72mm TB, and a new TPS intended for the RSX Type S (due Sun). I'm using K-Tuned parts, and boy, do they not like K-Tuner. Everytime I've called them with questions about setting up their products in K-Tuner, they make remarks about it. What the heck is that all about?

Anyway, the key issue here is the TPS base setting. I've set the previous 80mm TB & TPS to 0% in the software, however K-tuned has a note regarding stock & K-tuner installs on the web listing indicating that setting it to zero will result in fuel cut when driving in the conditions I describe above, so now I'm wondering if that has been part of my problem all along - setting it to zero instead of 1-2%?

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What is your opinion on the TPS base calibration & it's effect on drivability, considering the fuel cut condtion in question?
KTuner
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Re: More TPS & IACV Quirky Conditions

Post by KTuner »

We've outlined for many customers that they were selling a replacement TPS sensor that doesn't operate within factory spec for voltage outputs. Hopefully that's not the type you've gotten or they've finally fixed the range.

You have full control of fuel cut parameters to tailor when it occurs, so I'm not sure why they recommend that.
husseinholland
Posts: 122
Joined: Wed Sep 12, 2018 2:44 am

Re: More TPS & IACV Quirky Conditions

Post by husseinholland »

KTuner wrote:We've outlined for many customers that they were selling a replacement TPS sensor that doesn't operate within factory spec for voltage outputs. Hopefully that's not the type you've gotten or they've finally fixed the range.

You have full control of fuel cut parameters to tailor when it occurs, so I'm not sure why they recommend that.
Thanks for the reply. Can you direct me to the posts/thread regarding their TPS? I ordered one of the 'billet" TPS, primarily to make sure it is the correct RSX type S unit. They claim the internals are better quality to handle the vibrations on stiff mount swap setups

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KTuner
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Re: More TPS & IACV Quirky Conditions

Post by KTuner »

You can verify the voltages for closed and open. If they don't match factory spec and range then you have your answer.
husseinholland
Posts: 122
Joined: Wed Sep 12, 2018 2:44 am

Re: More TPS & IACV Quirky Conditions

Post by husseinholland »

KTuner wrote:You can verify the voltages for closed and open. If they don't match factory spec and range then you have your answer.
So, there is no way within K-Tuner to reference the angle % to a voltage value? I have to open the connector & check the values with a voltmeter?
KTuner
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Re: More TPS & IACV Quirky Conditions

Post by KTuner »

With a voltmeter.
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