Bad Wastegate Solenoid???

[TClassic]

OK, I have a LOW BOOST Problem, goes right to 11-12 lbs and Stays there!
Now the Obvious First think that comes to mind, on a Totally Stock car is Bad Wastegate Solenoid, but in 15 years of playing with these cars I've NEVER seen a WG Solenoid go bad, so my thinking is that it's the Hoses, there was a Bad batch of Turbo hoses from GM back around '98/'99 era so I thought that
maybe I was the lucky reciepient of one from the previous owner, so I bought a new Wye hose set, but first I bypassed the WG Soleniod and ran Tuner Style to Confirm and Sure enough I got Plenty of Boost.......So install the new hoses and BAM 11-12 Lbs again!! Theres no way to test a WG Solenoid either, so I guess I have to do a Search for one since thier DisContinued, Great?????

 

[Lee_Burough]

Vacuum hoses reversed after the "Y" ?

GN "Y" (has a different size aperature than TTA "Y") ?

 

[TClassic]

Lee,

Yea that was my first thought and I bought a NEW GM Hose set and put it on, but NO....... still low boost, and since it's fine when I tryed it Tuner style it must be the Solenoid, go figure....


In my 6 different Buicks over the years I've NEVER Seen a bad solenoid, but it looks like I must have one!! It's funny as everything else is so mint with this car..oh well...

 

[Lee_Burough]

Study This and see if it makes a difference....

 

[Lee_Burough]

From Salerno's website:

Low boost pressure
If your TTA is exhibiting low boost, the culprit is likely the plastic "Y", especially if the wastegate control hose assembly was recently changed. In the "Y", there is a metal restrictor which regulates the amount of boost pressure applied to the wastegate actuator. The size of the restrictor orifice is critical to proper wastegate operation. Originally, from the factory, this orifice was 0.040" in diameter.

The problem is the newer "Y"s have a larger (0.050") opening in the restrictor, which allows more pressure to reach the wastegate actuator. This in turn causes the wastegate to open sooner, which results in low boost pressure.The solution is to re-use the original "Y" with the new hoses.

Low boost will also result if the "Y" is connected backwards. Finally, if the "Y" was mistakenly replaced with a generic part there will be no restrictor at all, which results in very low boost of about 10 lbs.

 

[TClassic]

Lee,

I'm INTIMATELY Familiar with the WYE assembly problems and the Restrictor sizes, as I said earlier I removed what Turned out to be the STOCK FACTORY hose assembly and WYE, and it DID have the Correct size Orifice (to Reinterate it turns out that it was the FACTORY hose assembly)!!!!

So the ONLY other item it could be is the Solenoid, remember I said it Boosted as high as I wanted with the BLEEDER valve attached!!!

So like I asked, has ANYONE ever seen a BAD WG Solenoid, in FIFTEEN Years I haven't!!!!!!!

 

[TClassic]

Well it turned out to be the Solenoid...Go Figure....

 

[83ttypecooled]

I had the same boost situation when I bought my car, hoses were reversed.Still had low boost(10-12 psi), replaced the wastegate solenoid, boost went up to spec(16 psi or so). I just think the old solenoids get obstructed or sticky or something. Watch out for wrong map sensors, hard to tell a 3 bar from a 2 bar. By the way, wastegate solenoids are still available; my first AC Delco part even has the foam filter on it(put it on the Regal). The second one came without filter, TTA got that one.What a difference 4.5 psi makes!
Dale