Vac Pump Help!!

[JFerg65]

I'm packing the truck to make a 100 mile run for a quick vacation, I've been getting intermittant service engine soon light. I had a friend with a TECH II scan it and of course it through P0236. I ordered to have on hand a new wastegate solenoid, which has arrived and I through on just for good measure. ( thsi was the case with bot solenoids) I checked the vacuum at idle at the waste gate and.... nothing. I tried two gauges to make sure. The thing is, when the hose is put back on the wastegate it draws the waste gate closed, although it is slow.

I tried to pick up the vac reading where it comes into the solenoid, nothing.

I've checked for bad lines but every thing has been previously wrapped in loom and looks great.

I have no black smoke.
I have good power.
I have normal mileage.
The only thing that is odd, is that when I have about a half a tank of fuel the light does seem to go on more. I have gone and released the fuel cap and it is presurized... hissing. I have then gone and restarted the engine and the light is out. Is there any connection there? It worked on three seperate occassions.

Can the vac pump go slowly or is it something that stops suddenly? What happens if it goes enroute? Is this something I can limp home on? I am not towing anything.

Any suggestions??

The only thing I have not done as of yet is have somebody rever her up to see what I get with higher RPM.

Should I just bite the bullet and have a pump on hand?

This really is not making sense to me since I haven't had a code flash for several days and my driving has not changed.

ANY HELP / ADVICE WOULD BE GREATLY APPRECIATED.

[gmctd]

Vac at the pump - 26"HG at idle and 2000rpm

Vac at the WG - 15" at idle and 2000rpm

Plastic tubing deteriorates and crumbles

Rubberized end-nipples deteriorate and melt

[lfytsmith]

I am not replying as an expert, but my vac system is now in a box. If I had to replace anypart of it, I would go to a mechanical system i.e. Turbomaster from Heath Diesel. I took my vacuum system off and replaced it and am very happy. My boost went from max of 7psi to 14 psi. I can't see spending the money on a new pump.

[JFerg65]

Well... what all is involved in the change over? Do I need to worry about the tendency for it to "cause" any other gremlins to rear their heads? Any input on the installation and pros and cons would be appreciated.


In regard to the first post, thanks. I barely got 6 at 2000 rpm's. So I think I've got a problem, but why is the computer not kicking out codes continuously?

[DA BIG ONE]

Well... what all is involved in the change over? Do I need to worry about the tendency for it to "cause" any other gremlins to rear their heads? Any input on the installation and pros and cons would be appreciated.


In regard to the first post, thanks. I barely got 6 at 2000 rpm's. So I think I've got a problem, but why is the computer not kicking out codes continuously?

I dumped lots of $$$ into my vac boost control curcuit to try and fix it to no avail., "DUMP that VAC PUMP"!
Turbomaster (mechanical boost control) is an easy install, as for ugly heads of gremlins, too much boost will cause problems w/stock programming "fuel cutback", thinking 12psi is max, more boost to stock program keeps egt's down too. Aftermarket programs will allow slightly more boost w/o issues.

However, if you have egr solnoids (mine does not have egr) there may be an issue w/passing smog test, caution is best advise here.