ECMlink ISC diagnosis/ comprehension.

[miliman13]

So im looking for a bit of advice, direction maybe guidance.

finally have zero leaks at 30psi, and went back to smooth out my idle and i cant get link/isc to display anything besides zero once warmed up. (does show other values at start up> see log )

below is video of the isc.
Images of the resistance of the isc
and 2x logs at start up and warmed up displaying the isc


I have a solid diy biss screw, any time i adjust the butterfly or the biss the idle will fight me, it will drop then pick up...

And partly related once temp fans goes on the O2 seems to take a dump and my AFR's sink.

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My purpose? is my isc bad or not i cant tell ?
im trying to idle ..... at or below 850 with out surges....

 

[PlanZero]

The isc pintle should move in and out more than that. Replace it with a black IAC from a 98-99 DSM or any year 3kgt/stealth. The tan ones are known to fail.

 

[miliman13]

The isc pintle should move in and out more than that. Replace it with a black IAC from a 98-99 DSM or any year 3kgt/stealth. The tan ones are known to fail.

yeah that appears to be the common consensus.
if i could replace it now i would of, that's why i'm doing the thread for now.

 

[PlanZero]

In the meantime, try cleaning the pintle with some acetone and a brush.
Almost all of my tan ones acted squirrley

 

[miliman13]

Any reason why its always 0 on link ?

^ according to all my test this thing works, maybe not perfectly, but works according to all test.

Well looky-look at this.
https://www.amazon.com/Mitsubishi-P...m=1999:mitsubishi:eclipse&keywords=idle+valve

 

[pauleyman]

What is a DIY solid BISS?

 

[miliman13]

What is a diy solid biss?

http://www.dsmtuners.com/threads/red5.491289/page-5#post-153607897

This^ held 40psi

 

[pauleyman]

I don't think you know how a BISS screw works

 

[PlanZero]

Do not buy a $26 POS IAC. You are much better getting a new or used OEM. Standard and airtex/wells make decent aftermarket IAC for about $50. You can potentially damage the ecu using one of the thousands of junk parts on eBay or amazon.
Ive had several tan iacs "function" according to specs when I tested them but would still cause problems, hence the reason mitsu did away with them. Your pintle is technically working, but not to full extension/retraction. Look up some videos and you'll see the difference immediately.
Sorry, don't have link.

 

[miliman13]

I don't think you know how a BISS screw works

oh pauley, at it again i see.
How your responses resonate.....

 

[miliman13]

Do not buy a $26 POS IAC. You are much better getting a new or used OEM. Standard and airtex/wells make decent aftermarket IAC for about $50. You can potentially damage the ecu using one of the thousands of junk parts on eBay or amazon.
Ive had several tan iacs "function" according to specs when I tested them but would still cause problems, hence the reason mitsu did away with them. Your pintle is technically working, but not to full extension/retraction. Look up some videos and you'll see the difference immediately.
Sorry, don't have link.

I noticed the "properly working" one's have a vibration during rotation.
No link i get it, however im more curious as to the value on link on how to change it.
I've grounded any and all check boxes on link to assist in adjusting but no luck.

 

[PlanZero]

OK, I just replaced another one on a friends DSM and I wish I had the video. The old one acted like yours; the new one looked like a little dog pecker going in and out. Certain things you should upgrade on these cars for piece of mind anyway.

Wait- are you telling me you no longer have an adjustable BISS? If so, there may be one of the biggest problems. If you're just trying to fool the ecu into setting the base idle, that seems bizarre to me.
But what do I know, I don't have link, nor can I comprehend the concept of setting a tps via link.

Gotta go to bed; tooo many beers today.

 

[pauleyman]

oh pauley, at it again i see.
How your responses resonate.....

At what again? Don't like my answer? It wasn't sarcastic.

The BISS doesn't just close off that exterior hole. ISC wont adjust properly if you're feeding too much air across the BISS opening. ISC is probably doing its job.

 

[miliman13]

.......

Allow me to explain; since it appears to be necessary.
The nylon nut was modified; so its hollow
Why? so the bolt can be adjusted in or out through the nylon nut....

Look at it like this, instead of making threads for a bolt to fit in that location i placed a nut inside that with the bolt adjusted holds 40 psi.....

If you look at the pictures... you can see the bolt clearly in place (IF YOU ZOOM IN ) on the following response in my build thread..
Now that this has been cleared up for all. Let get past it.

 

[bling5tatus]

I'd get rid of that fuel filter in your valve cover venting system. Also, where on the BISS is a nylon nut? An oem biss with an oem o-ring and oem biss cap on it works great to not leak. Not sure why people freddy fuzzpucker their cars by doing stuff they read on the internet.

I've said it time and time again... most of us are not smarter than a TEAM of engineers on Mitsubishi's payroll.

 

[PlanZero]

^ miliman's fuel filter is a very common and useful mod to prevent oil blow by from entering the intake tract. It's a mini catch can. I like this kind, which I paint black but leave a sight line (this is on my gf's car):

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Although, miliman I do like the idea of using the umbaffled (eBay, I presume?) catch can as a reservior, I recommend replacing that line from the tstat housing. The nylon hoses that come with those cans are junk.

 

[miliman13]

^ miliman's fuel filter is a very common and useful mod to prevent oil blow by from entering the intake tract. It's a mini catch can. I like this kind, which I paint black but leave a sight line (this is on my gf's car):

You must be logged in to view this image or video.

Although, miliman I do like the idea of using the umbaffled (eBay, I presume?) catch can as a reservior, I recommend replacing that line from the tstat housing. The nylon hoses that come with those cans are junk.

Yeah it looks crappy too.
Cool pic by the way I like your filter....

It's unfortunate how easily people are distracted, it's a bit silly. If I use AutoCAD to design and build something for and used in a platform.... it becomes OEM, but wasn't it once an idea? People worship engineers, yet mock them.

Any way... I'm gonna asume this thread is only gonna further attract more
"red herring" comments.

 

[PlanZero]

Agreed. Thanks for clarifying the BISS. Once in a while you'll come across the no longer produced metal BISS in classifieds, which I am a big fan of. It's perplexing sometimes to look at the obvious small cost cutting downgrades between generations (BISS, BOV, etc)

Well here ya go, I ordered from these guys before and they stand by their used product. If it ever fails they'll replace it.
http://m.ebay.com/itm/Mitsubishi-30...lve-Stealth-MD628053-/152178894003?nav=SEARCH

 

[EGLTAWLN]

have you tried to adjust your biss screw with the engine running? when the isc goes to 0 with engine running can you spin the biss to get the isc to adjust?
when my isc goes to 0, typically my biss is set wrong...

 

[pauleyman]

have you tried to adjust your biss screw with the engine running? when the isc goes to 0 with engine running can you spin the biss to get the isc to adjust?
when my isc goes to 0, typically my biss is set wrong...

This was the point i was trying to make. Op you may have a home made biss but im still not sure it works similarly to the oem design. You should also check ecu. If i recall isc drivers are close to the typical leaking caps.

 

[miliman13]

No change on link when I adjust the biss screw.
But the engine will raise/lower rpms during adjustments.

My biss functions the same way, as an oem one. It blocks and opens the chamber that bypasses the butterfly.

Again I insist we remove the biss out of the equation.
I known you all mean well. But take my word for it, my screw is fine.

 

[pauleyman]

Then id say you have a bad isc or bad isc drivers in ecu

 

[EGLTAWLN]

I have had a bad ISC burn up a beautiful eprom ecu. Literal smoke coming off the board. If its not working, maybe unplug it so it doesnt hurt the ecu(if the ecu is still okay). Good luck.

 

[miliman13]

^ haven't checked ECU yet, it's not my daily...
Not yet, but of course that is what I'm working towards.


During my plethora of searchers, I read that another method of testing is to rotate the plunger if it moves it's bad, should be stiff.

Today I checked and it's loosie goosie"'
Waiting on a new motor.

 

[boost97gst]

Nice work. And thanks for the amazon "black" ISC. That's a gem. AND at a great price. Good one bro