looking foe vacume hose location help

[stinkydogfilms]

Hi,
Can someone tell me what the two ports at the top, on the backside of the intake manifold connect to? My car is running very rich as in black smoke and a rough idle. As soon as I drive, it clears up until the higher rpms just before the shift point and wants to sputter unless I give it more gas.

Is there a vacum hose schematic online anywhere?




Thank you,
Mike
sorry cannot change the title spelling foe should be FOR

[gadget73]

Those are coolant lines if you're referring to the two right behind the throttle body. Thats your EGR spacer, and it flows coolant through it either to cool it or warm it up, depending who you ask. Or its there to have a small gasket fail and force you and most other people to believe you've blown a head gasket.

The two red ones, one goes to the fuel pressure regulator, one goes over to the smog control solenoids on either the fender or next to the throttle body, depending what year you have.

There is a fatter line from the back center of the upper manifold to a vacuum tree on the firewall

there is a mid size line from the back center of the upper manifold to the MAP sensor, which should live slightly to the passenger side of center on the firewall, roughly the size of a deck of cards.

there is a larger line from front center of the manifold, probably looped through a Tee fitting on the lower rear corner of the manifold to the PCV valve

the other line on the front center of the manifold goes over to the battery tray area through a solenoid. This is the "suck the fumes out of the gas tank" system, aka evap purge

Check all of them, particularly the one to the MAP sensor. If the MAP line is broken or unhooked, it runs horribly rich. Also, a failed MAP will make it run like this. The only halfass reliable test I've seen for a MAP is to unhook the vacuum line. If it runs better with it unhooked, its probably bad.

[zoomie]

when the last time your timing chain was replaced?

[stinkydogfilms]

Not sure when the timing chain was replaced. The car motor was running great with no misses, sputter or hesitation until I replaced the fuel pressure regulator this past Sunday. I unbolted the intake and laid it aside so I could get to the fuel pressure regulator.

I did notice the FPR did not have a hose connected at the top of the FPR.. When I put the intake back on a couple of vac hoses were disconnected. I tried to hook them up. Some were connected with a rubber connector. I did not use sealant on the intake or gasket, I just bolted it back down. Would the intake possibly leak without sealent?
The motor was swapped in last October so the intake gasket was blue and looked good. There are no fluid leaks showing. Maybe an intake manifold leak? I did not use a torque wrench and did not want to overtighten the intake.

Which hose if any should connect to the top of the fuel pressure regulator?

I am taking off work on Friday to try and track the issue down.
My thanks again guys.

[stinkydogfilms]

Hey Gadget73

You hit it right on the money. I took care of a couple of the red plastic hoses that had been spliced and came apart. I started it up each time I connected a loose hose, with no results.
I am lucky to live literally 30 seconds from Auto Zone and 10 seconds more is NAPA. I bought some vac hose to replace the splicing then slowly got around to the MAP sensor which was.........................................
....................
..............................
............
.......................
.....UNPLUGGED.

THAT DID IT!

This time it fired up back to an almost normal idle without missing. It does idle a little fast which I will adjust tomorrow.

I am forever grateful to you and the forum for all of the help. I am sure I'll be back again.

I THANK YOU, THANK YOU, THANK YOU! quote GOMER PYLE USMC!

[gadget73]

Cool. When I swapped the intake on my car, it ran like yours was and I had a moment of panic. Everything ws hooked up, etc. Finally I pulled the hose off the MAP and it had no vacuum. the port on the intake was plugged up with crap from some insect, I assume while it sat around in the junkyard. After I reamed out the port to get rid of mr bug nest, it worked fine.

Most 86+ engines do not need a timing chain replacement before about the 250k mile point. Unless you got unlucky, in which case it will hop over about 120k and lunch the engine. Once in a while an 86+ motor shows up with that shitty early timing chain, and it seems totally random. HO engines can lose a timing chain with stock cams, and no real harm is done. The non-HO engines will bend valves because they don't have reliefs in the pistons.