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Car running badly after power fc

Old Mar 15, 2013 | 11:59 AM
  #26  
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Originally Posted by GoodfellaFD3S
The PFC doesn't read vacuum in inches of mercury

What are the VTA1 and VTA2 voltage readings at idle? If they're jumping by a tenth of a volt, that doesn't seem right.

Have you tweaked the screw in the front of the TB with the 8mm jam nut on it? Takes a flatblade screwdriver. Try adjusting the idle with that..... you may have to reclock your TPS however. If memory serves, at idle VTA1 should be between 0.1 and 0.7 and VTA2 between 0.75 and 1.25. Or vice versa
Yeah I converted it so I know what I should be seeing on the Power FC. The way it reads boost however sucks.

I have the Power FC out at the moment. VTA is for TPS? because that was just adjusted into spec a week ago. I couldn't say anything about ISC though. I just don't understand how the Power FC was running my car perfectly for the first day then all of a sudden goes bad. I was having a ton of backfire over every little throttle change. I still get some on stock ECU but their hardly noticeable.
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Old Mar 16, 2013 | 03:12 PM
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What would be the best way for me to setup the power fc to run my car correctly? Since I had a negative experience the first time. If only we had tuners in the Bay Area.
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Old Mar 16, 2013 | 04:39 PM
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initialize it and see if it runs correctly. also try disconnecting the commander as i mentioned to see if it helps, it's caused problems in the past. second hand units can be sketchy but i have never seen a PFC fail so far, not to say that they won't if it was previously installed on a car with a wiring issue that backfed through the PFC.
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Old Mar 16, 2013 | 06:26 PM
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The commander is a possibility. I certainly can't hurt to try.

You might also try disconnecting the power break booster at the manifold and plugging the port. I'm wondering if running without a check valve has damaged it. A broken booster can pass a lot of air. I've never seen this on a 7 but have on other cars.
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Old Mar 16, 2013 | 06:28 PM
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Take a picture of the voltage screen.

thewird
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Old Mar 16, 2013 | 08:51 PM
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I'll try those out. Good thing I hardly drive the 7 lol. Would it also help if I deleted some idle controls? Less things to cause issues and I believe the power fc doesn't need all of them to run the car?
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Old Mar 16, 2013 | 09:24 PM
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if you delete the idle controls then it will be more difficult to pass emissions, the car will want to stall at idle when cold and only idle below 1k when warm.
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Old Mar 16, 2013 | 09:31 PM
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Originally Posted by jayscoobs
I'll try those out. Good thing I hardly drive the 7 lol. Would it also help if I deleted some idle controls? Less things to cause issues and I believe the power fc doesn't need all of them to run the car?
I wouldnt I'd try reinitializing it if you havent before . and give it another go .
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Old Mar 18, 2013 | 01:32 PM
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Haven't had time to install power fc but I drove it to work today. Now while driving my idle is 1100 but if I shut her down and start her again idle is at like 600.
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Old Mar 18, 2013 | 01:46 PM
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Could be that your IAC is dirty or bad but I think that there's either a vacuum leak, the idle screw under the elbow needs adjusting per the fsm or both.
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Old Mar 18, 2013 | 01:48 PM
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I know ... Lots of opinions / ideas ... Just start eliminating things one by one.
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Old Mar 18, 2013 | 01:50 PM
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What a headache. I'll be working on it tomorrow. It's just so weird how the car idle completely fine before I installed the power fc. Everything was in spec.
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Old Mar 18, 2013 | 02:04 PM
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The PFC is out to get you it knows that the Adaptronic is taking over!

Couldn't resist that.

It felt like I was dealing with a hunting idle forever until I replaced my clutch switch. There are so many possibilities it can be a serious headache.
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Old Mar 18, 2013 | 03:55 PM
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Seriously lol. The adaptronic movement is getting too advanced. It's taking over power fc!

Yeah it's a major pain. Can I see the clutch switch on sensor check? Maybe it'll help me see if mines bad.
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Old Mar 18, 2013 | 07:20 PM
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Clutch switch should definitely be on the commander.


Could also test it with a $5 Harbor Freight meter.
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Old Mar 19, 2013 | 05:58 PM
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Looks like ill be removing the mechanical dashpot because of this thread.

https://www.rx7club.com/3rd-generati...talled-853278/

Then after initializing ill take a pic of my sensor voltages.
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Old Mar 20, 2013 | 03:48 PM
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Does the ECU need to be grounded through the bracket? My car is missing it and I just thought the ground on the harness is enough to ground the ECU. Maybe thats partly my problem and I hope it didnt kill the ECU. Although my stock one has been working like that.
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Old Mar 20, 2013 | 03:58 PM
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The PFC? No, not to my Knowledge. It was always held in by a bracket from my stock ecu. The bracket was held on by double sided tape so there was no ground there.
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Old Mar 20, 2013 | 04:03 PM
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Originally Posted by James Paventi
The PFC? No, not to my Knowledge. It was always held in by a bracket from my stock ecu. The bracket was held on by double sided tape so there was no ground there.
The only thing im thinking is with the ECU touching the bracket and the bracket bolted to the car it is grounding.
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Old Mar 20, 2013 | 04:08 PM
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the ecu does not require grounding through its chassis.
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Old Mar 20, 2013 | 05:18 PM
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This is at full warmed up Idle during Idle learn process. Idleing 850.

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Old Mar 20, 2013 | 09:45 PM
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So I went to drive around after idle learn. Wow super heat soaked idling for 30 mins. Was just at 3k and saw knock skyrocket. Scared me a bit.
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Old Mar 21, 2013 | 06:58 PM
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Although
Originally Posted by RotaryEvolution
the ecu does not require grounding through its chassis
the ecu bracket does need to be grounded. A few months ago I observed first hand just how "possessed" an FD ran without the ecu grounded. https://www.rx7club.com/3rd-generati...ttent-1021661/

Last edited by beckrx; Mar 21, 2013 at 06:59 PM. Reason: grammar correction
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Old Mar 21, 2013 | 08:43 PM
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Guess ill run a ground wire to the case as a extra.
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Old Mar 22, 2013 | 01:07 PM
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Originally Posted by jayscoobs
Guess ill run a ground wire to the case as a extra.
the harness should have a local ground that you bolt onto the car and connect near the ECU . with that wire grounded it should be enough , the case itself does not need grounding just that wire .

after reinitializing it how is the car running?

As for heatsoak make one of your things to view your intake air temp . I know my car never likes intake air temps above 45.

Last edited by Tem120; Mar 22, 2013 at 01:13 PM.
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