Found some of my vacuum issues.

[nutshot]

I got my Talon back from Idaho in May of this year. The mechanic working on it went over budget (slightly) and really knew very little about the car in general. After returning home, I had to park the car because of all the odd gremlins under the hood.

My car was stalling, idling rough, pulling to 4k rpm then making an odd vibration noise, and other assorted issues. I had tried fresh plugs and wires, all the free mods, CAS adjustment, and idle adjustment.

Now, I think I found one of the issues.

talon throttle body 1.jpg

talon throttle body 2.jpg

Sorry for the sloppy photo (camera phone), but that is the throttle body and intake manifold. The mechanic failed to install two of the bolts holding that mess together, creating a large vacuum leak.

My though is that anyone dealing with my symptoms may want to check for loose/missing bolts.

Hope this helps those as frustrated as me.

 

[RoasT BeeF]

Thats deff a huge vaccum and boost leak. You will notice a huge difference once you get that sealed off trust me.

 

[nutshot]

Thats deff a huge vaccum and boost leak. You will notice a huge difference once you get that sealed off trust me.

It's sealed. I re-sealed the gaskets on both sides of the TB, and I installed two 8mm bolts (13mm heads rated at 8.8). I still can't get the car to idle. I'm trying to find all the vacuum leaks. Is there a vacuum hose on the bottom of the cruise control body?

 

[steve]

Is there a vacuum hose on the bottom of the cruise control body?

Yes, but it's not connected to engine vacuum. There is a vacuum pump below the CC cable assembly to driver the CC actuator.

You might have better luck pressure testing your intake to find the leaks. Use soapy water and watch for bubbles.

Steve

 

[nutshot]

Yes, but it's not connected to engine vacuum. There is a vacuum pump below the CC cable assembly to driver the CC actuator.

You might have better luck pressure testing your intake to find the leaks. Use soapy water and watch for bubbles.

Steve

It idles now, before I tested. It jumps between 600-900 rpm, and when I turn it off then back on it might idle from 1000-1400 or not at all. Fun.

How do you suggest I pressure test?

Thanks, guys.

 

[steve]

How do you suggest I pressure test?

http://www.dsmtuners.com/forums/search.php?searchid=220803
http://www.vfaq.com/FAQlocator-intake.html

Steve

 

[nutshot]

http://www.dsmtuners.com/forums/search.php?searchid=220803

I can't find any pertinant info there. Thanks for trying, though.

http://www.vfaq.com/FAQlocator-intake.html

This is an intercooler pressure tester. I can't see how I would supply air to the intake manifold without it bleeding (rather quickly) through one of 16 valves.

I will try to connect with Pina Motorsports tomorrow. Thanks for trying, Steve.

 

[steve]

Sorry the search link no longer works. It was just a search to Intake Pressure Testing.

It doesn't matter if one set of valves is open. It only matters when both set of valves is open and that happens for a few degrees around TDC intake for each cyl. The odds are small that the engine stops at one of those points but you can make sure by turning the crank.

Yes that tester presurizes the entire intake from the turbo inlet back. Exactly what you need to make sure you don't have boost leaks and at the same time allow you to track down any vaccum leaks.

Steve

 

[nutshot]

Sorry the search link no longer works. It was just a search to Intake Pressure Testing.

It doesn't matter if one set of valves is open. It only matters when both set of valves is open and that happens for a few degrees around TDC intake for each cyl. The odds are small that the engine stops at one of those points but you can make sure by turning the crank.

Yes that tester presurizes the entire intake from the turbo inlet back. Exactly what you need to make sure you don't have boost leaks and at the same time allow you to track down any vaccum leaks.

Steve

Sweet! I apologize for the disbelief, you are most certainly the man.

 

[steve]

It jumps between 600-900 rpm, and when I turn it off then back on it might idle from 1000-1400 or not at all.

Did you make sure to flip over the brass strap attached to the TB so that the bolt runs through it and the screw on the other end attached to the top of the TB. It's there to ground the TB so the ECU sees the IPS close.

The other thing you want to check is your ISC http://www.stealth316.com/2-isc-iac.htm
(its the same one on DSM's) Then when your done reset the BISS as needed to set your
base idle speed http://www.vfaq.com/mods/BISS-1G.html

Steve

 

[nutshot]

Did you make sure to flip over the brass strap attached to the TB so that the bolt runs through it and the screw on the other end attached to the top of the TB. It's there to ground the TB so the ECU sees the IPS close.

The other thing you want to check is your ISC http://www.stealth316.com/2-isc-iac.htm
(its the same one on DSM's) Then when your done reset the BISS as needed to set your
base idle speed http://www.vfaq.com/mods/BISS-1G.html

Steve

No, I did not attach the brass strap to anything. It is screwed into the TB, and looks like it was meant to be attached to the bolt or stud that went threw the TB into the Intake Manifold. Cool, I will try grounding that. Thanks.

I will check the ISC and BISS settings too. You rock, man.