So I was trying to clean up the area near the T valve and when I moved some wiring harness back I heard a snap and noticed that I broke the orange colored vac. line that comes from the vacuum pump to the wastegate solenoid.

I have a 96 GMC 3500 6.5 ewithout EGR. So it only goes to the wastegate solenoid and then from there it goes to the wastgate on the turbo as a black line.

I would have tried a splice but it broke clean off of what looks like a "rubber boot" that I assume is what is pushed onto the vac pump to make the connection.


I drove the truck into work yesterday and back (about 80 miles) with no problems and took it easy on the pedal and rpms. While driving in today I had my "service engine soon" light come on. I do not have a code reader but will stop by autozone on the way home and have them read the code for me.

With no vacum getting to the wastgate what exactly does that mean? (I am fairly new to diesels) Does it mean that the wastgate will not open if too much boost is made - or does it mean that it is open now and not making any boost?

Should I be driving the truck?

As for repair where can I find a new vacum line harness and while I am at it I will replace the wastegate solenoid - any ideas? The vac lines are so brittle that while checking the route of the line it broke in two more places.

Without having ever seen a vac pump removed from the engine how does the line connect to the vac pump? If I get a new harness does it have that piece that snapped on mine which looks like a spark plug boot with the vac. line being the 'wire' if you will? Does that just push down? (onto the vac pump?)

Any help is appreciated!

~GOD BLESS~

john

 

It means you will have no boost and any black smoke from the tailpipe means high EGT's.

You may want to try and remove the broken piece of plastic line from the boot and get a double hose barb that size along with a piece of rubber vacuum line long enough and the right diameter to replace the entire orange line.

 

Thank you Racer55! That explains why the truck was driving a bit on the slugish side. As they say round here " I aint' got no boost!"

When I got into the GMC to drive home yesterday the "service engine soon " light was not on anymore. And it did not come on. I stopped by Autozone and he checked for codes and it had one stored - code P0236 - Turbo/Boost sensor a circuit range performance. Probable cause: low boost pressure. So that explains the light.

I decided to not drive the truck until I can work on it this weekend. It runs and starts fine but I want to keep it that way if you know what I mean.

Good suggestion to remove what is sticking out of the ruber boot and then use another plastic fiting to get a vacum line on etc... when I was looking it over last night it looks like there is enough vac tube left I should be able to get ah hold of it with some good needle nose pliers. But when I was looking at the connection to the wastegate that black line broke after its rubber boot. Then the orange line broke off at the sensor. Same story I guess as been told here before that the line has become so brittle from age and heat that it all needs replacing.

Does anyone sell the harness? I called local dealer and they said it was discontiuned.

Any suggsetions on where to get the parts would be appreciated (vac harness and the wastegate solenoid).

Thank you!

~GOD BLESS~

john

 

I wouldn't change the wastegate solenoid till it gives you trouble-just get some rubber vac line the right diameter and replace all the plastic line.

 

OK. That sounds like a plan. I will wait until the weekend when I can have some good wrenching time. Got the ole' truck backed into the spot in the woods where I can get at it Saturday. Been in the old car until then.

Thank you for your help - I'll let everyone know how it turns out once done. I'll try to get some pics as well.

~GOD BLESS~

john

 

OK. Great advice and I am sure it would have saved me some change too - but I caved in and bought a new vac harness and a new wastegate solenoid. Figured I would replace it as it was OEM. I'll let everyone know how it goes. I'll keep some spare vac line in the service body tool boxes.

Thanks again for the help!

~GOD BLESS~

john