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scarface8087
11-08-2004, 02:28 PM
well my first mistake was letting my wife use my 87 turbo t to commute
to work! one day i got in it & went for a quick spin,after my wife has been
driving it for a couple weeks ,i found boost would only get up to approx 3-4
psi ;engine seems to be running fine ,just a total loss of boost power.
powertrain is stock;no dtc's set;all vaccum lines appear to be connected
& free of damage(besides looking a little aged);i am a gm/truck mechanic,
i dont have too much exp w/ these vehicles or their turbo operation;
i haven't gotten to far on diagnosing the problem ,due to lack of resources.
does anybody hav any ideas on where to go w/ this?turbo & wastegate
operation on these vehicles?testing?etc... i tried opening the wastgate
while eng in park,2500-3000 rpm, i could not hear turbo spooling & found 0 boost on guage??? also where can i find a good book on testing these vehicles
..alldata & mitchell have no info on these turbo systems..another thing i thought was wierd, i when i first bought this vehicle about a year ago ,i found the vaccum line to the wastegate sol disconnected,however boost seemed ok w/ or witout this line connected.this was long before the problem i have now, however i thought it was strange.......does anyone know exh back
pressure spec,& where the best place is to take the reading?could a small
crack on one of the intercooler hoses near the clamp ,cause a problem this big?
...very frustrated & lost please help... :banghead:

FlyinGN
11-08-2004, 10:41 PM
you cannot make boost in neutral.. has to have a load on the engine to make boost.. I would checl that the wastegate rod is still attached.. Sounds like it may have fell off??

Keller
11-08-2004, 11:19 PM
Any hole in the IC hoses can bleed off all boost.

The wastegate solenoid only bleeds off boost to control it. With that hose off, it would act as if the solenoid was open and limit boost.

I would start by inspecting all three IC hoses for leaks. Then, check the wastegate control hose set and the hoses and lines that go out from the top of the throttle body. Any of these might be the problem.

Maybe your wife was just enjoying the car and its aging hoses couldn't keep up! :crackup:

There is a lot of data on this website. Dig in and read!

scarface8087
11-09-2004, 12:25 AM
well, i replaced the ic hses; wastegate rod is connected & vaccum lines
to wastegate sol are connected; problem still exist...why wont the turbo boost in park wot,w/ wastegate opened? :confused:

Keller
11-09-2004, 12:45 AM
First, wastegate must be closed to generate boost.

Second, engine must have load to generate boost. i.e. Be in gear. Don't try this while you are under the hood.

Do not run the car without the wastegate being under control or you will overboost and blow headgaskets. A very expensive way to learn about how the inside of your motor looks.