Anything special about our vacuum lines?

[4BY4ADV]

I installed a THOR cowl intake yesterday and due to locking my keys in the garage, I didn't get to fire it up until today.

Had to jump it(whole other topic), but once it was running, it wanted to idle around 3k. Throttle cable isn't stuck, it's got just the right amount of play, valve opens/closes easily.

So after reading a bunch, I see that the vacuum line running at the back of the firewall is a likely culprit. It is connected at both ends, but there was a near 90 degree bend in it and it is a much stiffer plastic than I was expecting. Tried to straighten it but it appears to like that bend. So I'm thinking I should replace it to rule that out, but i doubt I'll find that at a local Oreilly/Autozone/etc.

Anything else I should be looking at? I didn't mess with the anything electronic or near the throttle body. Only other thing I can think that might have an effect, I unplugged the harness at the back of the firewall to have access to cutting the firewall. In other vehicles I've had issues with old harnesses and too much movement breaking old brittle wires, but I don't have any codes and other than high idle, I was able to drive around to charge the battery with no issues.

Thanks!

 

[TJ4Jim]

You need to hands on trace each vacuum line and fitting from the intake manifold to each terminus. The rubber ells tend to perish over time and can look fine to the eye and the tube can crack. Most auto parts stores carry generic vacuum tube and fittings in the help section, even O'reilly's.

 

[Turdworlder]

Can you check vacuum accumulator? Its under battery, if its absent then its most likely they plug closed it with something(bolt,rubber) and its leaking.

 

[4BY4ADV]

I did that, using a diagram you posted in another high idle thread. In other vehicles I've worked on the vacuum hoses were always rubber, and finding that this one is more like a hard plastic hose I figured I'd ask.

See, I tried to do my homework.

 

[Turdworlder]

Also how is your brake booster?

 

[4BY4ADV]

Can you check vacuum accumulator? Its under battery, if its absent then its most likely they plug closed it with something(bolt,rubber) and its leaking.

I didn't see a vacuum hose going in that direction, so that's a good call. I guess that means it's time to install my blue top. haha

 

[TJ4Jim]

I did that, using a diagram you posted in another high idle thread. In other vehicles I've worked on the vacuum hoses were always rubber, and finding that this one is more like a hard plastic hose I figured I'd ask.

See, I tried to do my homework.

That's how it's done so have at it, can be frustrating at times.

Another simple testing option is to have it running and remove one line at a time from the manifold and plug the nipple with your finger to see if the idle comes down to normal.

 

[Turdworlder]

I had/ having same problem. My booster is leaky. It happens after cold nights and hot day change. The diaphragm is affected by temps, natural pressure i guess

 

[TJ4Jim]

I didn't see a vacuum hose going in that direction, so that's a good call. I guess that means it's time to install my blue top. haha

The reserve canister is under the battery and connects to the plastic line with a tee where it enters the cab next to the heater hoses.

 

[4BY4ADV]

Also how is your brake booster?

Didn't see any damage to the hose. Also didn't get near it during the intake install. Brakes were great when I went into the office a couple hours ago.

 

[4BY4ADV]

I have zero flippin clue at this point... Swapped batteries, the vacuum accumulator or whatever the under battery piece is called, it was there. Pushed the button in and out a few times and it wasn't stuck.

Put the blue top in and crossed my fingers as it's been sitting on a trickle charger (two blue tops in series used as an external battery for a UPS), started it up and it runs great. No clue what fixed it, but I at least no where to look if it happens again.

Jeep sounds MUCH better at normal idle. Now to see if my intake is still noisy as ****. Guessing with the THOR-CI it will still be loud. hahaha.

Thank you for all the help!

 

[TJ4Jim]

I have zero flippin clue at this point... Swapped batteries, the vacuum accumulator or whatever the under battery piece is called, it was there. Pushed the button in and out a few times and it wasn't stuck.

Put the blue top in and crossed my fingers as it's been sitting on a trickle charger (two blue tops in series used as an external battery for a UPS), started it up and it runs great. No clue what fixed it, but I at least no where to look if it happens again.

Jeep sounds MUCH better at normal idle. Now to see if my intake is still noisy as ****. Guessing with the THOR-CI it will still be loud. hahaha.

Thank you for all the help!

Pushed the button in ? Don't think your looking at the reserve canister, the canister is a black plastic container or box as shown as #8 in this diagram. #3 is the plastic vacuum line you located running across the firewall so look for tee #2 and follow that to the reserve canister

 

[williambmac]

unplug the IAC and see what happens. Also try doing a global reset. Disconnect both battery terminals and touch them together for about 30 seconds. This will drain the capacitors. Reconnect everything and see what happens. I'm not sure what killed your battery, but low battery voltage can cause wacky things to happen