I have a 1995 850 GLT non-turbo with 140,000 mi. When I purchased it, it was throwing a code for Egr problems, 1-5-4. I finally figured out that there was a sheared off vacuum line. I can't figure out where it's supposed to go.

There is a vacuum hub on the right front side of the engine. It has hard emissions tubing running to the throttle switch under the fuel rail. It has another running to the EGR controller above the fan shroud, which then runs to the EGR valve. The picture attached shows the new hub. The old hub had a regular vacuum line with a white/yellow stripe heading out of the left (engine) side. That was the line that was sheared off. Where did it go? Also the black hard emission tubing coming off the other side is capped off.

Does someone have a picture or some direction as far as where these are supposeed to go? The car was running ok, getting 22 mpg until it recently began to hesitate during idle, whether in park or at a stop light. Now it hesitates while driving and seemingly hesitates during acceleration as well as decelerates quickly and refuses to coast. These codes were collected the day it started to hesitate:
4-4-3, TWC eficiency
2-3-2, Long Term Fuel Trim Part Load
1-2-1, MAF sensor
2-4-1, EGR System Flow Malfunction

The timing belt was changed when it was purchased in February. The rear O2 sensor was replaced in March. I run 87 in it. 93 makes no apparent difference. I pulled the EGR valve after these codes were pulled. The EGR valve was totally full of carbon. It was cleaned and reinstalled.

Someone please give me some direction.

 

I suspect you have an EGR valve that is hanging open, and/or the vac lines for it, or its controller, are hooked up incorrectly. Unfortunately i gotta run; will ck back tomorrow... if you post more pics of these errant vac lines, i can look at mine; have same car.


Code 1-5-4 (EGR System Leakage)
1) Start and run engine at idle. If engine runs unevenly at
idle, go to next step. If engine runs smoothly at idle, fault is
intermittent. Go to step 5).
2) Operate engine at idle. Disconnect EGR connector. If
engine still runs unevenly, go to next step. If engine now runs
smoothly, check wiring between EGR controller connector terminal No. 1
and ECM terminal A40 for a short to ground.
3) Operate engine at idle. Carefully remove Yellow hose from
EGR controller. If engine still runs unevenly, go to next step. If
engine now runs smoothly, test system using new EGR controller.
4) Operate engine at idle. Carefully remove Yellow hose from
EGR valve. If engine still runs unevenly at idle, test system using a
new EGR valve. If engine now runs smooth at idle, check if Yellow hose
is blocked or kinked. Replace as necessary.
5) Check wiring between EGR controller connector terminal No.
2 and ECM connector terminal A40 for possible intermittent short
circuits to ground. Ensure EGR controller is operating. Ensure EGR
valve is not sticking.

 

I appreciate the EGR info and I'll check that shortly and report back. I did take a short video to show you what I'm working with. Here's the link.
http://www.youtube.com/watch?v=D_cc2k7xrzw.

 

So I think that I solved my own problems. Maybe you can confirm that I did this right. I bought a new flame trap and housing since there wasn't one in my car and the housing was busted. When I got the new one from Volvo it had a nipple on it. I suspect that is my missing vacuum connection. I hooked all of that back up, replaced the mass air flow sensor and have had no stutters, smooth idling, better shifting and more power. Problem solved? I'll report back if anything changes. If you have more suggestions please let me know.

 

Well it seems that all is not fixed. All of my systems have not registered yet but I already have one code. It's P0172. So the car is still running to rich. I plan on cleaning the front oxygen sensor tomorrow. The rear one was replaced about 2 months ago. Any suggestions.

 

Ck out this info for P0172:
OBD-II Trouble Code: P0172 System Too Rich (Bank 1)

Also, you said the rear O2 sensor is new; is it OEM? I (and others) have found you need to use OEM O2 sensors on these cars, and you may need to replace both together. Otherwise you may get codes that don't make sense.

And ck under your hood for a vacuum line map; use it to double ck your lines are hooked up correctly.