fuel status 1 issue

Hany
Posts: 28
Joined: Sat Oct 07, 2017 2:56 am

fuel status 1 issue

Post by Hany »

08 TSX AT ECU, forced induction speed density base map (only changed injector size) , when in open loop under heavy load (70%+ TPS ,8psi) and above 3500 rpm it's switching rapidly between fuel status 4 and 1 as shown in log screen shot.

when it switches to fuel stat 1 it reduces duty cycle and increases timing.

I replaced the primary O2 with another OEM one with no change, ECT, TPS, MAP and everything else remains consistent.

what could be causing this?
Hany
Posts: 28
Joined: Sat Oct 07, 2017 2:56 am

Re: fuel status 1 issue

Post by Hany »

my attachment is not showing up for some reason
KTuner
Site Admin
Posts: 3744
Joined: Mon Jul 22, 2013 8:13 pm

Re: fuel status 1 issue

Post by KTuner »

I don't have any suggestions, as we don't change anything related to fuel status code, but that base map is a starting point not meant to be under heavy load.
Hany
Posts: 28
Joined: Sat Oct 07, 2017 2:56 am

Re: fuel status 1 issue

Post by Hany »

I understand that base map is only a strating point, I do have a tuned map that runs much better and it was doing the same thing, I went back to base map to rule out any tuning mistakes/issues or flashing errors..

I can't seem to attach my log or at least a screenshot.

I appreciate your input on this as I have never seen such behavior before , I only ever see fuel stat 1 for a few seconds after a cold start which is normal.
KTuner
Site Admin
Posts: 3744
Joined: Mon Jul 22, 2013 8:13 pm

Re: fuel status 1 issue

Post by KTuner »

Try to see if it does the same at a lower pressure.
Hany
Posts: 28
Joined: Sat Oct 07, 2017 2:56 am

Re: fuel status 1 issue

Post by Hany »

Lowered the boost to 7 PSI and that seems to cure it but need to do a few more pulls to confirm, looking back at older logs the issue starts as soon as I go over 8 PSI (max boost was 8.4)
any idea what's causing this?
KTuner
Site Admin
Posts: 3744
Joined: Mon Jul 22, 2013 8:13 pm

Re: fuel status 1 issue

Post by KTuner »

I don't have any suggestions, as we don't change anything related to fuel status code.
Hany
Posts: 28
Joined: Sat Oct 07, 2017 2:56 am

Re: fuel status 1 issue

Post by Hany »

The fuel status switching has mostly stopped (stays in open loop) but the issue still continues with cutting duty cycle in half and I get a rapid zigzag duty cycle pattern and the only trigger is the ECU seeing MAP above 8PSI

Here are the 2 tests I did to figure out if there are other variables involved other than MAP reading going over 8PSI and triggering this issue.

I used a AEM FIC piggyback to manipulate only the MAP sensor signal

first test I increased MAP sensor signal using an AEM FIC piggyback by 15%, so when the ECU sees 8PSI in reality it's only 7PSI ( confirmed by both AEM built in MAP sensor and my boost gauge) the issue starts immediately and the ECU cuts fuel pulse to half , and I get a zigzag duty cycle!

In the second test I do the exact opposite and clamp the MAP signal so it never exceeds 7.6PSI while in reality I'm running closer to 9.5 PSI but the issue never happens and the engine keeps pulling to red line.

I'm trying to attached screen shots of the log but I keep getting the "Sorry, the board attachment quota has been reached" error
KTuner
Site Admin
Posts: 3744
Joined: Mon Jul 22, 2013 8:13 pm

Re: fuel status 1 issue

Post by KTuner »

That's good info and is starting to make sense. You are exceeding the MAP upper voltage error limit set by Honda which is bringing it to a default MAP error value you'll likely see in datalogging during this event.
Hany
Posts: 28
Joined: Sat Oct 07, 2017 2:56 am

Re: fuel status 1 issue

Post by Hany »

Is there any way to change that limit to at least make full use of the stock MAP sensor 10 PSI range? I expected a limit like this would be removed by Ktuner

I noticed in data logs that MAP value kept increasing so the ECU has no issue reading more than 8 PSI , it only disrupts the commanded duty cycle and timing

wouldn't that cause a CEL?
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