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Discussion Starter #1
Hey guys-

So 2.5 weeks ago I posted that I replaced my TCV (kept it OEM) since my other failed. I then followed the ipd learn procedure thinking any TCV would benefit from it, and it has never felt quite right since.

I posted about how the car seems to surge off and on really subtly and quickly while under load at high speeds on the interstate. I'm wondering if the learn procedure made it too touchy/responsive.

Someone checked VIDA and apparently there is no learn procedure for the OEM TCV. I want to reset the ECU and just drive the car normally and see if it makes any difference.

So, how do I do that? Unplug the TCV? Disconnect the battery? Pull a certain fuse?

Thanks for your thoughts!
 

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Disconnect both battery cables (negative first) and touch them together for 3 minutes. Then reconnect them (positive first).


Just a thought...who replaced your TCV? Have you checked for kinks or holes in the vacuum lines?
 

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i have never reset my ECU.
 

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Discussion Starter #4
Disconnect both battery cables (negative first) and touch them together for 3 minutes. Then reconnect them (positive first).


Just a thought...who replaced your TCV? Have you checked for kinks or holes in the vacuum lines?
You touch them together for three minutes straight or you touch them together after three minutes?

I installed it myself (major pain in the arse!) I guess I will try to see if I can see anything, but all looked fine when I was done. The problem is I can't really see the lines all the way back to where they go, plus I'm not exactly sure where two of them ultimately end up.

It's weird because the car pulls strong from 0- , and I only notice this slight surging when at high speeds under load.
 

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You don't really need three full minutes, but it doesn't hurt. And, the ECU is constantly monitoring the TCV adaptation, so even without the reset it will happen. The reset just starts over from square one.

The most important thing to remember is to not call for full boost while it's adapting. You should accelerate steadily, not sharply, and not more than half-throttle. If the TCV swings over to full boost, that tells the adaptation to pull back sharply, which means it has bad data and starts all over again. Basically, drive it normally and it will happen more quickly and accurately. The IPD instructions are a good guide.

If it doesn't adapt, then look for hardware issues. Vacuum lines with leaks, or plumbed to the wrong port, are a common issue. And don't lose sight of the possibility it isn't the TCV at all. You never know.
 

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Discussion Starter #7
You don't really need three full minutes, but it doesn't hurt. And, the ECU is constantly monitoring the TCV adaptation, so even without the reset it will happen. The reset just starts over from square one.

The most important thing to remember is to not call for full boost while it's adapting. You should accelerate steadily, not sharply, and not more than half-throttle. If the TCV swings over to full boost, that tells the adaptation to pull back sharply, which means it has bad data and starts all over again. Basically, drive it normally and it will happen more quickly and accurately. The IPD instructions are a good guide.

If it doesn't adapt, then look for hardware issues. Vacuum lines with leaks, or plumbed to the wrong port, are a common issue. And don't lose sight of the possibility it isn't the TCV at all. You never know.
Great advice! I disconnected the battery like 7 hours ago since I started another project. I'll touch the leads together for a couple minutes and call it done.

I think when I was doing the ipd procedure I was closer to full throttle (no boost gauge here). I am in the process of checking my plugs for inaccurate gapping. They have nearly 40K on them. Then I'll check for vac line issues. I am certain that I placed the right hoses on the right ports.

Anyone know the OEM gap? .030 or .028? I'm finding conflicting evidence.
 

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I don't have a boost gauge and didn't have any trouble with the adaptation, so don't sweat it. Here is the key paragraph from the ipd instructions. Note the "half of maximum" bit.

http://www.ipdusa.com/files/product/419/PI%20396%20HDTCV%20P1%20INSTALL%20INSTRUCTIONS.PDF

IPD Instructions said:

After the installation of the ipd HD TCV drive the vehicle for 5 minutes without developing any boost
pressure to allow the engine to warm up. In a safe and appropriate place, accelerate the vehicle
to approx half of its maximum boost level and hold there for 5-7 seconds, then decelerate to below
30mph. Proper accelerator modulation will be necessary to control the boost level. Repeat this 4 times.
Turn the engine off and wait for 12 minutes. For optimum results the above procedure should be

performed twice.

 

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Discussion Starter #9
^^ That's exactly what I used, but I think I got a bit heavy on the throttle. I'm just going to drive normally, not crazy stomping of the gas. Thanks again for your help!
 

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When resetting ECU, what data is erased? Will it keep remap? Lost software updates?
 

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When resetting ECU, what data is erased? Will it keep remap? Lost software updates?
I disconnected my battery for over 7 hours, then touched the cables together for 2 minutes, and when I restarted the car, the only thing lost was the clock??? My stations were all stored, trip/mpg data etc...

Software updates shouldn't be lost.
 

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When you disconnect the battery presets and remap are not affected. What is reset is the adaptive driving system (and yes the clock as well). The system tries to adjust to your driving to optimize engine performances. When you remove your battery 10/15 minutes it resets itself to factory values I believe. All sensor data are cleaned as well so you might get a CEL for about a day until the system has relearned. I do that if I remove my tune for service.
 
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