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Topic: Missing EGR vacuum line w/ pics (Read 922 times) previous topic - next topic

Missing EGR vacuum line w/ pics

I pulled KOER codes and got a 34 - EVP-EGR didn't respond and 22 - MAP out of range (even though the MAP held vacuum when tested yesterday).

There is a vacuum tube that was cut off by some backyard mechanic and closed off with a screw. I put it on the EGR and the car ran like pure . So.... where does it go?

I tried to test the vacuum on the EGR but the tubing I had to work with didn't fit right. There was a small leak between the black hose and the vacuum pump's hose and the vacuum slowly died out every time. It appeared that it may have held a vacuum with proper tubes.

Whatcha think?

Missing EGR vacuum line w/ pics

Reply #1 –
The vacuum to the EGR is controlled by the EEC with a solenoid controlled vacuum valve.
The vacuum hose on the EGR should go to the EGR control solenoid.

On the 3.8 it is under the coolent expansion tank. Not sure where they are on the 5.0.

Missing EGR vacuum line w/ pics

Reply #2 –
your egr may have been plugged do to a possible leak or a sticking valve.
Which in your case sounds like the problem,since when you hook up vaccum it runs like .
Under normal cirspoogestances your egr only opens under deleleration,but if it sticks or leaks it will cause the engine to run lean(vaccum leak) and it will run like  and possibly even stall.
Get a new egr or just leave it plugged.

Missing EGR vacuum line w/ pics

Reply #3 –
If you have a vacuum gauge, you should have full manifold vacuum at the MAP at all times.
At idle there should be no vacuum at the EGR.

Missing EGR vacuum line w/ pics

Reply #4 –
that must have been the problem. I hooked up a line with full vacuum all the time where I should have run a line from the manifold. I found a few vacuum diagrams but apparently there are multiple possible setups for my 85 5.0. I have almost narrowed it down, but there are some acronyms that i don't quite understand.

Missing EGR vacuum line w/ pics

Reply #5 –
Quote from: btwodu;132010
that must have been the problem. I hooked up a line with full vacuum all the time where I should have run a line from the manifold.


??? A line from the intake manifold will be full vacuum at all times.
The line to the EGR should come from a solenoid valve that is opened and closed by the EEC.

Quote
I found a few vacuum diagrams but apparently there are multiple possible setups for my 85 5.0. I have almost narrowed it down, but there are some acronyms that i don't quite understand.


What are the acronyms? I may be able to tell you what they mean.

Missing EGR vacuum line w/ pics

Reply #6 –
I think I even confused myself on that first statement. I meant the solenoid valve (not manifold). Anywho.

Here are the 2 sheets I think are most like my setup. There are a ton of broken and brittle hard lines that desperately need to be replaced.

What does HCV, CWM, VOTM, V CK V, and VCV. Thanks

Missing EGR vacuum line w/ pics

Reply #7 –
HCV- Exhaust Heat Control Valve
CWM-Cold Weather Modulator
VOTM-Vacuum Operated Throttle Modulator
V CK V- Vacuum Check Valve
VCV- Vacuum Control Valve (this is a guess)

Missing EGR vacuum line w/ pics

Reply #8 –
This may be closer to what you have. It is from the 84 Shop Manual.
You will notice the CWM is on the air cleaner and controls vacuum to the vacuum motor that operates the hot air/outside air door in the air cleaner snout.
I think this is what you have. But double check it with the decal on the fan shroud.

Missing EGR vacuum line w/ pics

Reply #9 –
This is from the 84 Shop Manual. I think it may be closer to what you have. Notice the CWM is on the air cleaner and controls the vacuum to the vacuum motor that operates the hotair/outside air door in the air cleaner snout. Double check the decal on the fan shroud.

 

Missing EGR vacuum line w/ pics

Reply #10 –
Low and behold...
 
After taking the fan shroud off I found the vacuum diagram under an inch of crud staring me right in the face. After a little scrub it s clear as day. SWEEEEEEEEET. Thanks guys. (I feel dumb now lol)