Jeep Engine question

[AndyN]

there is a tube coming from somthing located under the throttle control all i know about it is that it pulls in air and it looks like it is supposed to be connected to somthing and the engine stalls when you stop the air from coming in. its obviously some kind of air intake but shoulnt it be connected to some kind of filter?? someone please help ie been looking for answers to this for some while now....:drummer:

[neZZr]

Sounds like the vacuum line to the brake booster. You'll probably notice problems getting your vents to change to anything but the defrost position, and your cruise doesn't work... not to mention the lack of power assist for your brakes!

There are a few other vacuum hoses, but usually they're not large enough to cause stalling problems. If it is your booster hose, get it fixed ASAP!

[over's tj]

Ok, I'll be the first one to play

year make and model? post up a pic.

sounds like a breather line disconnected from air intake tube


or just put in a Ford small block

[AndyN]

its a 97 Wrangler i cant get a pic right now but i will put one up soon the tube it sits right under the air intake but i dont see anything to hook it up to it dosnt give me any problems atleast that i have noticed...

[yellow_X]

4 or 6 cyl?

[neZZr]

Here's the one I was talking about. Your's might connect in a different place on the intake depending on the year, but it should be the same on the booster.

http://dailydriventj.com/images/seafoam/2.jpg

[AndyN]

yes i just looked that up in the repair manual i have but m pretty sure thats not it because my brakes work fine

[AndyN]

it is a 4cyl

[AndyN]

i believe it is a vaccume hose, maybe a leak detection pump?? i have no idea is that a personal pic very clean hah

[neZZr]

i believe it is a vaccume hose, maybe a leak detection pump?? i have no idea is that a personal pic very clean hah

Leak detection pump is part of the evaporative emission system, it has nothing to do with engine vacuum. You'd have a check engine light on and it wouldn't affect how the engine runs at all.

What you have is definitely a vacuum hose, the question is where does it go? What is the diameter of the hose? Smaller than the pic I posted? That wasn't my pic BTW... just found it with a google image search.

Right now you're running with a constant vacuum leak, so 1st thing I'd say plug the hose. It might stall it initially when you plug it, but that is because you're engine is compensating by closing the IAC, and it can't handle such a sudden change. Just fold over the end and clamp it with a couple of zip ties, or put a screw in the end.

That's just temporary though, until you find where it goes repair it.

[AndyN]

it is a small plastic tube and it is insulated?

[AndyN]

yes smaller than the one id say a quarter inch diameter

[AndyN]

and not to get off subject but would you know anything about liquids dripping out the exhaust?

[over's tj]

Does it look like the engine bay is all stock/factory? did you do any mods?

anyone with a 4 cyl TJ that could look under the hood to help this guy?

maybe you could look at a similer one at a used car lot or dealer if you can find a four cyl.

or try looking chiltons or hayns repair manual at auto parts store, they may have them in plastic these days

[neZZr]

Are you having trouble with any of the other things I mentioned? Cruise control? Heater duct selection?

Water dripping is normal, though it will be dirty. If you're getting coolant (smells sweet) then you might have a larger engine problem. All bets are off until you fix that vacuum leak though.

[over's tj]

and not to get off subject but would you know anything about liquids dripping out the exhaust?

water/condensation is normal out the tailpipe and the weap hole in some mufflers (the colder the more water an engine will produce

if it oily you have more serious problems

[neZZr]

Could it be your crankcase vent hose? The picture below shows the 6cyl, but it's the same diagram for both engines in the FSM. The hose at the bottom of the picture that is shown connecting near the side of the valve cover is for the 4cyl.

[AndyN]

its a 97 should it have cruise control?? because it dosnt have it to my knowledge and it dosnt have anything in the haynes repair manual

[dirtbuggy]

I have an 04 tj four banger will look at it in the morning and report back hope this helps.

[neZZr]

its a 97 should it have cruise control?? because it dosnt have it to my knowledge and it dosnt have anything in the haynes repair manual

It probably isn't standard on 4cyl models, but it was an available option... both factory installed and as a dealer add-on.

[AndyN]

now that i think about it the heat does come out of the top one when its set to the bottom would the vaccume hose effect that?

[AndyN]

water/condensation is normal out the tailpipe and the weap hole in some mufflers (the colder the more water an engine will produce

if it oily you have more serious problems

what happens i the water is oily?

[AndyN]

the crankcase vent hose is probablly it im looking at the picture in the haynes book and it shows it insulated where is that supposed to be attached to?

[over's tj]

what happens i the water is oily?

dirty but water like is ok, for example, if it drips on the concrete floor, an hour later it should be dry but a dirty dark spot, if it has oil mixed in, it will not dry up and will feel like oil in between your fingers

if oil, and your engine has alot of miles it could be valve seals leeking, bad rings or other cylinder head problems, but if you have a major vacume leak, that has been unchecked for a while it may of caused some type of pressure/vacume imballance in crank case that caused it

[over's tj]

the crankcase vent hose is probablly it im looking at the picture in the haynes book and it shows it insulated where is that supposed to be attached to?

I think it should go to the top of the valve/rocker cover, is there a open hole up there? if not look over that engine compartment carefully to find a place it would likley go

I have a '97 4.0 since new and cruise was not a factory option till I think 98 or 99

[AndyN]

dirty but water like is ok, for example, if it drips on the concrete floor, an hour later it should be dry but a dirty dark spot, if it has oil mixed in, it will not dry up and will feel like oil in between your fingers

if oil, and your engine has alot of miles it could be valve seals leeking, bad rings or other cylinder head problems, but if you have a major vacume leak, that has been unchecked for a while it may of caused some type of pressure/vacume imballance in crank case that caused it

im not sure if it is oily i will have to check tomorrow, do you know where the hose would be attached to? and would this effect noise of the engine at all? just out of curiosity?

[over's tj]

im not sure if it is oily i will have to check tomorrow, do you know where the hose would be attached to? and would this effect noise of the engine at all? just out of curiosity?

you are talking about out the tailpipe right? also, rub your finger inside the tailpipe tomorow before you start it, if it is wet/oily then there may be more problems, if it dry but gray/black soot like, that should be ok

on where does the hose go? if it is the crankcase breather, then one end is usualy connected to the intake manifold (the aluminum part that the throttle body is mounted) and the other end to the valve cover (black metal cover on top of engine) directly with a plastic/rubber connector or sometimes with a PCV valve

on noise question? it would sound like a vacume leak or a air leak under hood and while driving

[TanTJJim]

now that i think about it the heat does come out of the top one when its set to the bottom would the vaccume hose effect that?

Just in case someone missed this. I'm sure someone can take it from here.

And FYI, condensation from the exhaust is normal. There is actually probably a little hole in your muffler specifically for draining water.

[neZZr]

On the 4cyl the crankcase vent hose will connect to a check valve on the valve cover, looking at the picture I posted above, it should be near the front of the engine, probably on the side of the cover.