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A couple more questions for the experts.....

gnel

gnel

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Location
Jalisco,Mexico
Let me start by saying these questions have come about since I had my IP rebuilt and I installed it. That was a couple of weeks ago.
Today I finally put some clear return lines on my sub. No bubbles from the IP to the hard return line but lots of bubbles from the passenger side return line:(. I must of done something to the rubber return lines? I am not seeing or smelling any diesel and the truck runs fine. Is this something I need to repair right away or ever? Can this damage anything?
My next problem is that since I installed this rebuilt IP I´m not getting the same boost #s I was before. I haven´t seen more than 4. My vacuum numbers are spot on but I can move the wastegate manually at idle. Its stiff but movable. Could the recalibrated IP not be comunicating correctly with the computer? Please bear with me as this is the first diesel truck I have owned with an electronic IP and a computer:???:. Thanks for any replys. Gus
 
Are you sure you didnt just crimp or break the boost gauge line somewhere?

You checked vacuum at the wastegate actuator itself? I would suspect a vacuum line could have been cracked.
 
Thanks for the replys.

I pulled the boost guage line off and it checked out. I have 25 from the vacuum pump and 15 at the actuator.
 
If you can monitor vacuum while driving you can see if its losing it at the actuator from a crack that opens under load.

You installed the IP yourself, did you make sure it is timed correctly with a scanner, or the KOKO method? Does it drive smoothly? Is there an SES light?
 
Put a mitey vac tester on the WG actuator itself see if it holds , I had a diapraghm in one of mine go bad once; the rest of the system was good but actuator was leaking and not allowing full vac to sustain the WG being closed at highway speed exhaust flow thus limiting boost.

Remeber it only thakes a little open of the WG flapper off it's seat to reduce the total boost that makes it to the engine.

You should not be able to move the WG arm on the turbo @ idle
 
buddy said:
If you can monitor vacuum while driving you can see if its losing it at the actuator from a crack that opens under load.

You installed the IP yourself, did you make sure it is timed correctly with a scanner, or the KOKO method? Does it drive smoothly? Is there an SES light?
Click to expand...

No I don´t have access to a scanner and am unfamiliar with the koko method. It drives smoothly with no ses lite. I´ll try and find someone with a scanner in Guadalajara but that won´t be soon as I live 5 hours away. If I can´t find someone I´ll have to wait until Xmas. Buddy I´ll be heading up to the bay area for xmas. Maybe you want to make a little xmas money?? Thanks for the replys. gus
 
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Turbine Doc said:
Put a mitey vac tester on the WG actuator itself see if it holds , I had a diapraghm in one of mine go bad once; the rest of the system was good but actuator was leaking and not allowing full vac to sustain the WG being closed at highway speed exhaust flow thus limiting boost.

Remeber it only thakes a little open of the WG flapper off it's seat to reduce the total boost that makes it to the engine.

You should not be able to move the WG arm on the turbo @ idle
Click to expand...

Sorry I don´t have a mitey vac tester. I changed out the vacuum lines and still have the same results. This morning I ran the line direct from the vacuum pump and could not move the waste gate arm. I then drove it and have boost galore. 5@2000rpm,7@normal accel,and around 14@ hard accel. To much me thinks.

So could the actuator function with 26 inches but not with 15? Or is there something else that could cause this? Thanks for the replys. gus
 
Oh, you have a 95, my bad, I was thinking it was a 96. The KOKO method is not available for you. So a Tech1, Tech2, or I use GMTDScanTech on my laptop, which doesnt cost a whole lot. there is even a free version you can try out, it wont allow you to set timing, but see how the program works and get you all the sensor data. You would just need to purchase a GM OBD1 ALDL cable to USB, and have a computer you can use.

TD could be right that the actuator could be leaking and not able to hold against the turbo drive pressure. Although with enough arm strength I imagine you could move it against 15" of vacuum on the actuator's diaphragm.

For now you could try hooking the vacuum pump straight to the actuator, see if losing the lines and solenoid resolve the issue. Or throw a screen door type spring on there to assist the vacuum system. CrankMe69 has a thread about that. Both would help determine if its actuator related or drive pressure related. Maybe timing is too retarded. Does it have good power, drive strong?
 
gnel said:
Sorry I don´t have a mitey vac tester. I changed out the vacuum lines and still have the same results. This morning I ran the line direct from the vacuum pump and could not move the waste gate arm. I then drove it and have boost galore. 5@2000rpm,7@normal accel,and around 14@ hard accel. To much me thinks.

So could the actuator function with 26 inches but not with 15? Or is there something else that could cause this? Thanks for the replys. gus
Click to expand...

Well you already accomplished one of the tests. Thats good, perhaps the solenoid has failed or you had the vac lines hooked up backwards.
 
bison said:
No.
If you have vacuum in the tank you could be sucking air trough a cracked injector return line anywhere along that bank.Or you could have a bad injector letting in air trough the nozzle under compression.[/QUOTE

I have no vacuum in the tank. I drilled a small hole in the locking cap to be sure. My injectors were just rebuilt (with german bosch nozzles ) about 5 mos. ago and I installed all new return lines. Any other ideas? Another thing is that when its cold it shows no bubbles but as it warms up it gets worse and worse. Thanks for repling. gus
Click to expand...
 
Well you already accomplished one of the tests. Thats good, perhaps the solenoid has failed or you had the vac lines hooked up backwards.[/QUOTE]

The solenoid is new (5 mos.) and I tested from the vacuum pump 26 and then from the solenoid to the acuator 15 wich I´m assuming means its correct. Heck I´ll go out and reverse them and test again. Thanks Buddy.
 
It could be that there is no air in the IP housing from the fuel inlet. But Bison may be able to comment if it is possible for air to enter when the plungers are filling before injection?

Or since you just changed an IP, but the injectors 5 months ago, have you used ether or any other strating fluid trying to revive the truck with the failing IP?
 
buddy said:
It could be that there is no air in the IP housing from the fuel inlet. But Bison may be able to comment if it is possible for air to enter when the plungers are filling before injection?

I thought air was the enemy.

Or since you just changed an IP, but the injectors 5 months ago, have you used ether or any other strating fluid trying to revive the truck with the failing IP?
Click to expand...

No ether was used since the new injectors were installed. The truck always started even while the IP was dying.The PO did use ether a couple of times. What would ether do to cause air?
 
gnel said:
Thanks ak. Thats a good idea. Got any tricks for getting at the lines under the turbo?
Click to expand...

I don't think you would have a problem doing this temporarily. Try bypassing the passenger side injector returns. Run tube from just after ip and to the return line going back to tank. Put a catch pan on the line from the injectors as they will still be returning fuel too. This would tell you if its the pump or one of the injectors or the hoses. This to me would be easier then if it clears up you can test like AK suggested to isolate the issue.
 
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gnel said:
No ether was used since the new injectors were installed. The truck always started even while the IP was dying.The PO did use ether a couple of times. What would ether do to cause air?
Click to expand...

ether could damage the injectors maybe help keep one staying open and have compression pushing air into it while its not squirting fuel out.
 
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