So, I had a mechanic that I know look at an oil leak for me today, and he pointed out this unconnected vacuum line. (White circle)



The line with the yellow circle is just plugged. I looked in my haynes manual and decided that the unconnected line should be hooked up to my pressure sensor, which I discovered wasn't connected to anything! (that's the big hose in the picture.)

So, I connected them and my car immediately started running very roughly, with an erratic, low bouncing idle. I took it for a trip around the block to see if it would stabilize, but halfway around the block it died. (It was revved up to about 7k once in neutral right before it died.)

Now, the engine starts up easily enough but immediately dies. If I give it gas and keep it at 2k RPM or above it will run, but the moment it drops below around 1.5k RPM it dies. Also, it backfires after high revs now. It didn't backfire often before this happened. Any suggestions? This is my daily driver and I need it to drive to school tomorrow morning!



By the way, I unplugged the pressure sensor after this started and I still have this problem.

 

you didnt mess with the yellow circled one did you?

 

make sure you plugged your afm back in and you could try turning the flathead screw on top of the throttle body to rais the idle. it may have been adjusted to compensate for the leak to begin with.
if its niether of those id think you left a large vac hose off somewhere

 

I'll try raising the idle, i remember lowering it when i first bought the car, so you're right it was adjusted for the leak.

 

That wasn't it, i tightened it all the way down and it still wouldn't run, so I loosened it a lot and it still wouldn't run.

 

No, i didn't mess with the yellow circled one. Why?

 

Bump. About 5 hours before I go to bed, it'd be nice to have my car running in the morning :]

 

it sounds like a halfassed clusterfuck from a previous owner. Best way to do it is start from scratch. Pull the manifold and double check all the vacuum routing and gaskets. Check that all your sensors are plugged in and in spec, then set the idle according to the factory procedure using the initial set coupler.

 

ever check the afm plug? if you pulled off the intake snorkle you probably forgot to plug it back in. its the black plug that goes into the bottom of the silver box your intake air passes through directly after the air filter.

 

OKAY, I fixed this. A little background info on my car:

Sometime this last year, i had some troubles with the O2 sensor, the car is consistently running rich. Because of this, I think that if both of the vacuum tubes shown in the picture above are plugged, the engine runs too rich and tries to bog. If one is left plugged and the other bare, the engine runs fine. If both are left bare, the engine runs faster, possibly because it's becoming more lean. Anyways, this had absolutely nothing to do with my car not idling. Hah.


On the air intake tubing, after the AFM but before the intake funnel, there is an elbow coming off of the bottom of the tubing. This was connected to the BAC like it is supposed to. For some reason, there's also ANOTHER elbow coming from the same rubber port or whatever you want to call it that the first is in. This wasn't connected to anything, and as far as I know never has been. I don't know why it recently prevented idle. Anyways, as soon as I blocked that second elbow my smooth purring idle returned.

Now I have one vacuum tube (yellow circle) bare, the other (white circle) connected to my pressure sensor, one elbow off of the intake tube connected to my BAC, and the other elbow capped. Anyone know what that second elbow was? Is my tubing from a different model or what? My Haynes only shows one elbow.

 

Bump. Any thoughts?

 

I don't know what its for but on all the fcs I've seen that elbow is factory capped.

after you fixed that did you retry capping the circled nipple on the intake manifold?