Been working on a Volvo 240dl (1987) and ran into emissions problems come test time. Results are as follows-

HydroCarbons (HC) in Grams/Mile: 5.47
Applicable Standard: 1.60

Carbon Monoxide (CO) in Grams/Mile: 14.43
Applicable Standard: 15.00

Oxides of Nitrogen (NOX) in Grams/Mile 2.78
Applicable Standard: 2.50

Wondering if anyone has suggestions for the first and last test levels.

*Not sure if this is related* but I noticed a melted vacuum line that looks like it connects to the computer behind the passenger headlight. Does anyone know what this is and where it connects to/controls? Would this affect emissions?

This is the first car I've gotten into mechanically and appreciate any help the VolvoForum community throws my way.

 

that computer is the ignition controller, and that vacuum is used to calculate timing, its quite important. those 85-88 240's had chrysler ignition controllers, with bosch LH 2.2 fuel injection. the electrical connector to the ICU can be a cause of problems. in 1989, they switched to lh2.4 and ezk116, where the ICU is above the drivers footwell. the ECU is next to the passenger door on all of these..

 

Is there a right way to repair/replace these? Or is a trip to the local pick-n-pull in my near future?

 

Our 1987 240 is out of state with my daughter, so I don't remember the routing of that vacuum line, but its mostly thin hard tubing, with rubber tube splices. one end plugs into the nipple on the bellow on the bottom of the ICU, the other end plugs into the main vacuum tree by the throttle body somewhere, but I forget exactly where. be gentle with the electrical connector on the ICU, do NOT rock it if you unplug it, it has to be pulled straight out or the pins will be loosened

 

Unless it has been painted over, every 240 I have owned has a vacuum routing diagram under the hood. Usually right at the front by the radiator.

The stiff black plastic tubing can be purchased at any parts store. I picked some up at Autozone.

 

Didn't even think to check the diagrams under the hood. I knew there was a few there but haven't taken a second look at what they really are.

tubing I pulled was a tan, very small (in diameter) tubing- Is that along the same lines of the black plastic tubing you are thinking of? Color might have been due to age. PO's took very poor car of the vehicle.

 

it was probably white when it was new, yellows to a sort of tan with age. the black stuff is pretty much interchangable. as I said, my 240 isn't even in this state anymores, daughter has it up in Oregon, but IIRC< there's a right angle rubber elbow right at the vacuum tree on the throttle body, and maybe 2 lengths of the thin hard stuff connected with another rubber tube, plus a rubber tube on the end that goes into the ICU. I'm trying to remember if it goes up-and-over the valve cover, or goes around the lower front of the engine. obviously, keep it secured well clear of the belts!

 

Will have to look at the engine bay when I'm with my car again. Thanks for the help thus far guys!

 

the parts catalog for a 1987 shows it as a 1550mm tube, with a rubber elbow at the throttle body, and a different rubber right angle 'connector' at the ICU. it doesn't give the diameter of the tube, however. pictures in some of the service docs show the tube goes around behind the ICU, so this would suggest it ends up going over the top of the valve cover, but thats just guessing.