Only 5 psi

[1986_TURBO_Z]

I am only getting 5 psi right now on my 86 shelby charger (2.2 TI log/a525)
I have checked all the solenoids, and it has all new vacuum line everywhere, etc
The only code I am getting is a 17 (I don't think thats the problem)

what could I be missing?
I should at least get 9psi, the car has a mp computer that is calibrated to run 11psi....

The only thing I can think of is in the wiring diagram I noticed there is a "orifice" in the wastegate line, is that what I need??

also on the wastegate solenoid ,(on the passenger side of the enginie bay)the vacuum source plugs into the top of the solenoid, and the line that goes to the wastegate goes to the one kinda at the front of the solenoid correct?

thanks
steve

[tkelly27]

you NEED the oriface. The orifice makes the bleed have more of an impact on the wastegate, and without it it will be as if you are directly running the line to the wastegate, hence the 5psi. Not really sure how its all hooked up, mine works and thats all I know! : )

[1986_TURBO_Z]

hmm, what does it look like? I know its kind of like a vacuum T, except it is straight, but is there a certain size or colour? I ask colour because I might still have the old vacuum line kicking around which still has the orifice on it.....

[88jbody]

well on my car all of a sudden I lost boost and it turned out to be the hose going to the recirc/BOV was off, and I still was geting about 5psi

[speedyshelby16]

log car wouldn't have a bov. The orifice in my 85 SC was yellow and one end had a brass orifice and the other end was strainght open. Just put in line with the waste gate hose.

[1986_TURBO_Z]

Quote:

Originally Posted by speedyshelby16 log car wouldn't have a bov. The orifice in my 85 SC was yellow and one end had a brass orifice and the other end was strainght open. Just put in line with the waste gate hose.

thanks for the info, I was just planning to get a g-valve instead, it should fix the problem

[speedyshelby16]

You still need the orifice with a g valve. Where you tee it off the end the side that gets open to the outside needs the orifice. But you can't find one just go and get a wire feed welder tip that .030. That what I'm running on both my Td with the g valve.

[DartGTS340]

Sounds like other than the computer your car is set up as stock. No bleeds or other mods to the waste gate curcuit?

If that is the case then you should still be able to get to full boost. The orifice diameter controls the response time of the wastegate curcuit and boost spiking inversely. Too large of a diameter or not one at all, and the boost will come up slowly to max setting. Too small of one, and your boost will spike way up , and you'll hit overboost cutout. If it is just right, the boost will spike quickly without hitting cutout and settle into the level your ECU is set up for.

I'd be looking elsewhere to solve the problem before starting to play with bleeds. Do verify that you are connected to your wastegate solenoid correctly. And of course check that your turbo to manifold plumbing connections are tight.
Someone else might be able to jump in on this one, but if the coolant temperature sensor is not working correctly, could it keep you from getting into closed loop operation, and the computer is keeping you at 5 psi on purpose? My Shelby Z will not make full boost until it goes into closed loop operation.

[tkelly27]

Yes! go g-valve and don't look back! You don't actually need the oriface. I broke/lost mine while putting in the g-valve and instead I used a vacume cap with a small hole drilled in it. Oriface is just easier.

[1986_TURBO_Z]

Yeah there are no mods to the car at all, I checked today and it turns out that the yellow orifice is still there (when I redid the vacuum lines I used it as a connector to hook up my wastegate line anyway...lol) I plan to try the g-valve and see what happens. If not I'll have to look at the wastegate can itself, as maybe it isn't working like it should.

It can boost to 11 psi, but its kinda hit and miss when it happens, I usually have to get the car to 4k+ to get it to 11psi, but this only happens some of the time. Any other time it will only go to 5psi. I can tell this has been happening since I have bought the car, because when I finally got it to 11 psi that one time it felt like a whole new car

thanks

[leemel]

Hello all,
Just signed up today. I also have the 5psi boot problem. I have an 86 shelby glhs but I had to reassemble. When I purchased the car, the engine was removed so I proceeded to install a T2 crate motor and a A555 trans. No mater what I do I can only get 5psi it really sucks. If I plug the wastegate solenoid line and bring the car up to about 14psi, the engines cuts out just like it's supposed to so I know the computer is reading the pressure right. I don' t know what else to do. I have looked over the vacuum lines who knows how many times, no error codes on the computer, so i'm at a loss. Anybody have any other suggestions on what to check. I'm not into putting after market boost controllers and such in so recommendations like that are not an option.

Thanks
-Lee