I took a trip to hell and back here recently. Illinois to California and back pulling a stock trailer. All in the middle of blizzards and horrible luck with my truck and now I wanna get down to fixin it, but I need some suggestions as to what the fixes may be.

I knew I was low on power but think I found the problem with that, being the cracked wide open exhaust manifold. Even with the new one I still don't think I am getting the full affect of the turbo. Boost numbers still seem low. I have to really hammer it to hold 20psi for any time at all. Typically it climbs to 12-15 and then starts to fall. I run the Comp on 2X2 setting for daily driving.

I also had an oil pressure problem. I was running hard on the way home and the truck hadn't been shut off for over 22 hours when I noticed oil pressure was dropping when I would let off the go pedal. When I shut the truck off to check it I was 1 1/2qt's low. This truck has never used oil. Leaks like hell, but it's like magic, never been a drop low. I stopped and had the oil changed and poured in a qt of seal conditioner/stop leak stuff and since then it has not lost a drop. Have put on 3000-4000 miles since.

I knew my Vaccuum Pump has been leaking bad for a long time so I planned on re-building it, but now it has stopped leaking and the truck is holding pressure just fine. My biggest question is, would the leaking Vac pump affect my pressure like this or should I be looing for another problem?

 

Still lookin for any un-educated guess.

 

Well, the first thing that comes to mind is a boost leak. Have you thoroughly inspected all the boots? Pay real close attention to the lower one on the passengers' side since there is a known problem with the inner fender cutting a slit in it. It may look like fine when you look at it, but it can swell some and really get bad. You may also want to pull the intake off your turbo and build a leak tester to assist you in finding the leaks. You will probably find multiple leaks that way, just about if not all trucks have some small leaks.
Far as the oil pressure problem, 1 1/2 quarts low didn't have any affect on the pressure. Chances are the oil pressure sending unit is beginning to fail. They are another known problem. You need to find the right one, since the "upgraded" one from a dealer will require a reflash turning your gauge into nothing more than a fancy idiot light. I will do some looking and see if I can find the part number you want. You will also need an extra deep 1 1/16" SIX point socket. I had to purchase a deep well socket and cut the drive end off in order to weld another socket on to make it deep enough.
Tom

 

Sorry I didn't include it in the original message but ya I have tested for boost leaks several times. Even used the soapy water on all the joints and connections and couldn't find anything other than the boost fooler elbow for the Comp, leaking off slowly.

 

So have you tried to adjust the boost elbow? I am wondering if your waste gate is opening so you can't build boost.

 

I put a new elbow on and it still does the same thing, when I called Comp they said that the elbow was supposed to leak off pressure like that. Don't know anything about how to adjust it. I don't pretend to know anything about the turbo or waste gate to know how to adjust that stuff. I check the blades and look for excess play when I do an oil change but that's the extent of my knowledge there.

 

You definatly have a leak somewere. I can push 24PSI all day with just an EZ and nothing done to the turbo. I would try clamping off the waste gate and see what happens.

Andy

 

I'm game, now somebody tell me how to do it.

No fancy words here, were talkin diesels for dummies, with pictures if you got'em. The turbo and the insides of the motor are the last places of this truck I haven't ventured an rebuilt yet.

 

HERE is an article authored by our own Diesel Minded!! This should give you a better idea for the wastegate, Dennis.

 

just take a small pair of vise grips and clap the hose, and take it for a ride ,t his will tell you quick if it is the problem. It doesnt have to be tight just enought o pinch the hose together.