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2G PLEASE HELP I BROKE MY CAR

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Talon Cooke

Proven Member
32
4
Jan 27, 2020
Winnipeg, MB_Canada
first post here. completely new to the dsm world. Perhaps stupidly i bought a heavily modified 2g talon tsi. It has a huge list of parts that have been installed including bigger turbo, cams, forged internals, injectors to name a few. Long story short the car was idling high when i received it, did some research and came across the biss screw. I tried simply turning it counter clockwise to lower the idle ( it was pretty much all the way tightened when i started) it fixed the idle but then it started stalling after i would rev it/ drive. As the rpms would come back down it would stall out. So i tried closing it again, this is when the problem started. The screw became stripped and i could no longer close it back to where it was. So after trying forever i completely mangled the soft copper screw... So i tried tapping a flat head into it to get it to turn, this worked but i couldn't get it to stop stalling. I tapped the screw more to turn it again but by now the screw was right down to the rubber gromet thing and it is now almost in half but it is still seated in the threads and turning. I started the car once more and it barely started now.. also it would barely respond to me pressing the throttle. It would clunk around and make all sorts of horrible stalling clunking noises. I tried a few more times and it now sounds absolutely horrid when trying to start and keep it running. Im very scared as this car is now my daily driver and i need it to work! IM worried that from tapping the screw with the flat head that a piece of it broke off and went into the throttle body and got sucked in? would this cause the horrible clunking/stalling sound? please help im dumb and dont know what to do now.. the car wont even run anymore... all because of me turning this stupid screw that i should have just left alone.. please some one help me
 
Yeah dude. Not a great start.
ECMLink?

The high idle can be quite a number of things.
Use ECMLink to view parameters to assist you in your diagnostic processes.
Search for setting TPS, setting ISC with link, etc. This should make sure you’re in the ballpark with you ISC and BISS.
We’ll need to know quite a few things regarding the modifications.
Make a DSMProfile w/ as much information about the car as you can possibly provide. This will expedite the process when it comes to people helping you out.
 
At a minimum your going to have to recover what's left of the BISS screw and replace it. After that your going to have to do some of the basics so we can help you walk through it like Bleakley mentioned.
 
idek what ecm link is, ill look into it...

god i think i got in over my head with this car, It wont even start.. im so scared that a piece of that screw got sucked into the engine while i was adjusting it.. Does this sound like a possibility to you? the screw is now broken and im not sure if its even creating a good seal down there anymore.

As i was adjusting it before it died i noticed air suction coming from the biss screw hole

would the biss screw not being seated properly be enough to stop my car like that? and make all those bad sounding noises before it died? it wont even start at all now.

i feel like puking... boys, im so scared
 
Last edited by a moderator:
would the biss screw not being seated properly be enough to stop my car like that? and make all those bad sounding noises before it died? it wont even start at all now. i feel like puking... boys, im so scared

Do you have a wide band?
Where do you think this sound is coming from in the bay?
The biss has an O-Ring. If it’s sucking then you need to get it out and replace it.
 
yes i do have a wideband. i just went out and tried again, turned the screw down as much as i could and tried started it. It ran while sputtering for a while until it stalled out and then didnt start again.. the screw is definitely not creating a tight seal anymore.. i managed to actually grind the screw down past the o ring.. so its pretty much useless i guess.. i really hope the reason it wont run anymore is simply because the screw.
 
yes i do have a wideband. i just went out and tried again, turned the screw down as much as i could and tried started it. It ran while sputtering for a while until it stalled out and then didnt start again.. the screw is definitely not creating a tight seal anymore.. i managed to actually grind the screw down past the o ring.. so its pretty much useless i guess.. i really hope the reason it wont run anymore is simply because the screw.

What does your wideband read while at idle?
it’s leaning out if you’re sucking air through it. Probably causing the noises you hear too.

Do what @tk106 said.
Be sure to remove the throttle body to avoid shavings.
 
What’s likely happening here is you’ve closed the screw so much that the car won’t idle. You can effectively snuff the car out of air if it’s turned in fully. Turn the screw out about 2.5 turns and try again. It’s unlikely, but possible, that you broke something, under the top of the biss screw. It’s like an inch long. Go ahead and order another with a new o-ring. Idle issues are very easy yet complicated to fix . By that I mean there are 10 reasons why your idle is messed up. Each of the things are easy to do but nonetheless it’s 10 things to do. This website is your god if you have idle issues:
https://www.sixsigmatuning.com/dsm-idle-control
 
so the screw either popped out or got sucked in the engine... just went out and tried again, loosened the screw all the way. tried and it started and sputtered then died. Got out to look at the screw and it was gone... completely so it either fell into pieces and got sucked in while trying to run the car , or it popped out and fell somewhere in the engine bay / ground. I couldnt see it anywhere. Now im really scared
 
Biss get sucked in?
...not possible.
That screw is plastic. Doubt you did anything bad. Learn how the idle circuit works before you go messing with stuff. Get a new screw and bring.
okay this is good news. Never the less, the screw is now missing. Will the car not run or start without it? i find it hard to believe that its not starting anymore because of the screw missing,, i feel like it should still start and run
 
Does it run if you give it throttle input as your cranking it over? can you keep it running with your foot on the accelerator?
 
Jesus bud, please RELAX and take a deep breath, eh? Let's not rush to FUBAR conclusions just yet.

Firstly, to lower the RPMs at idle, you need to thread the BISS in (clockwise). This makes it go down the threads and close the gap so less air goes through the bypass channel. By turning it counterclockwise, you bring the BISS up the threads, making more air pass by, thus increasing your idle. Now, there is a controversy behind how to mess (or not mess) with the BISS in general, some saying that it could fry your ISC controllers and so on. Let's assume that hasn't happened yet.

Additionally, the OEM BISS is entirely made of hard plastic and a standard o-ring. Even in the case of a part breaking off and getting sucked into the combustion chambers, 99% of the time it will melt almost immediately and get flung out the exhaust ports. HOWEVER, it is impossible for the whole BISS to get "sucked in", simply because of the way the bypass channel is designed. It doesn't poke straight into the throttle body. Check this picture out that I edited with my amazing Paint skillz. You can see roughly how BISS sits in relation to the air bypass channel.

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Now, before we continue with anything, you'd need to go ahead and order an OEM BISS. Additionally, you may as well take the TB off, but that will require you to drain some coolant (not all of it) and also order two new TB gaskets. If you decide to take it off, you can try blasting the bypass channel with air to get any *potential* BISS bits stuck in there.

Next, I would advise you to do three very simple checks. Firstly, if your car has the stock MAF, check whether the MAF connector is properly plugged in. Afterwards, if your Talon is a '97-'98 model, check whether your CPS (camshaft position sensor) plug is properly plugged in on the top of the sensor (mounted at the end of the intake camshaft). Also, when you were trying to crank it, was the Check Engine Light coming on and off multiple times?

Lastly, in the picture, you can see a small philips head screw locked by a nut, just underneath where the throttle cable attaches to. That's the "SAS" Speed Adjustment Screw. It determines the default (set by the factory) throttle plate position when closed (pedal not pressed). Sometimes people mess with that screw when they shouldn't. To make sure it's set in the standard position, loosen the small 8mm lock nut, unscrew the bolt, then thread it in just until it touches the throttle cable mount. As soon as it touches it, screw it in 1 full turn, then another 1/4 turn. Lock the lock nut and double check whether your throttle plate slams shut against the the screw.

Please do these things first. And when you get your new BISS, thread it all the way in (clockwise), then back it off 2 full turns as a general rule of thumb. If NOTHING else is wrong with your car, it should start up and idle as usual. IF you keep getting issues, let us know and we'll keep troubleshooting.

Good luck!
 
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