The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Fuel Injector Clinic
Please Support Fuel Injector Clinic

2G Idle increase after FP intake, FP exhaust manifold

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Sjd6795

Proven Member
614
121
May 14, 2014
Wilsonville, Oregon
Since my idle increased after installing these I'm almost certain this was the reason LOL. Fully warmed up my idle is around 1500, prior to install my idle was probably around 800. Could this also be due to my blown turbo though? I'm thinking about leaving the FP exhaust manifold on but changing the FP intake back to stock.
 
I'm guessing a throttle cable thats too tight or a gasket leak on the intake somewhere, what did you do about your egr valve? did you plug it?
 
I'm guessing a throttle cable thats too tight or a gasket leak on the intake somewhere, what did you do about your egr valve? did you plug it?
Intake manifold is stock. The intake I'm talking about is the turbo intake pipe. Throttle cables havent been touched. Only thing was intake pipe and exhaust manifold and the idle changed.
 
Intake manifold is stock. The intake I'm talking about is the turbo intake pipe. Throttle cables havent been touched. Only thing was intake pipe and exhaust manifold and the idle changed.
Ahh, ok. well then I'm not entirely sure what is going on.
 
More air is getting into the engine than should. It's as simple as that.

Are AFR and fuel trim still reasonable at idle? If yes, you have air leaking past the throttle body. You can try adjusting the idle set screw to see if that has any impact but short of a stuck throttle cable or dead ISC valve, that means it's time for a TB rebuild. If trims are adding fuel because it's running lean, you have a vacuum leak after the throttle body. Checking vacuum at idle isn't an appropriate way to diagnose leaks. If you have a boost leak tester, use it. If not, there are other ways but building and using a BLT is both easier and cheaper. And cleaner and safer.
 
Last edited:
Placed my stock intake back on the car and started the car to let it idle just to see if I notice anything. I could hear a little air noise near the throttle body so I started feeling around with my finger and noticed the air noise stopped when I put my finger over the gap between this black thingy and the throttle body.

I have some black silicone coming that's rated for engine gasket up to 500 degrees, would this be ok to use to seal around the leak?
 

Attachments

  • 20200314_132828.jpg
    20200314_132828.jpg
    1.2 MB · Views: 106
No. That's the throttle position sensor and needs to stay adjustable. There is a small seal underneath it that you need to replace. I understand that it's one more thing that no one wants to do, but parts are like $10 and it takes 30 minutes to do. One seal on either side of the valve shaft and some rubber gaskets for ISV and FIAV. It's also the perfect opportunity to disable the FIAV if you have ever had problems with that.

The TPS sensor is not sealed internally, so using RTV to seal it to the throttle body won't solve your problem. It will just make things messy.
 
No. That's the throttle position sensor and needs to stay adjustable. There is a small seal underneath it that you need to replace. I understand that it's one more thing that no one wants to do, but parts are like $10 and it takes 30 minutes to do. One seal on either side of the valve shaft and some rubber gaskets for ISV and FIAV. It's also the perfect opportunity to disable the FIAV if you have ever had problems with that.

The TPS sensor is not sealed internally, so using RTV to seal it to the throttle body won't solve your problem. It will just make things messy.
Can't find the TPS seal for the life of me.. I'm only finding throttle body gaskets when searching. Also how do I go about deleting the FIAV? As far as I know I don't have any issues with it but if I can prevent one why not.
 
Can't find the TPS seal for the life of me.. I'm only finding throttle body gaskets when searching. Also how do I go about deleting the FIAV? As far as I know I don't have any issues with it but if I can prevent one why not.

There is no TPS seal, only the shaft seal that you already found. If you aren't deleting the FIAV or ISC then you don't necessarily need to get the gaskets for those if they're not leaking. I had to do it because I was swapping valves, but it's up to you.

This post describes how to disable the FIAV without disassembling the TB or buying a blockoff plate. There isn't any benefit to doing this unless you're having idle surge issues but on the other hand I've never experienced or heard of anyone south of Canada having any problems once doing this, so if you want to you could do it as a preventative. https://www.dsmtuners.com/threads/free-fiav-block.391977/

If you're not familiar, the FIAV is designed to be open when the engine is cold to raise the idle even higher until coolant temp is enough to expand a spring and close the valve. Over time the spring gets weak and doesn't close all the way, hence idle surge. With it disabled or blocked off, the engine gets less air on cold starts. Could be a problem if it's particularly cold but it's not an issue for most of us.
 
Last edited:
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top