low power

[d.h.]

I posted this question late last year just haven,t had time to do much.I have only 4lbs boost(max).I did a 200 mile trip on the weekend,climed a 8%grade empty egt900 deg and boost only 3lbs.I replaced wastgate solenoid,checked for leaks in line.i/c has no leaks all is tight.The truck runs like there is cork up the exaust.Has anyone ever had a wastegate seize.Just a thought as it feels like it,s being held back by something.The lever moves freely but thought it was worth asking.
I even removed cover on air cleaner and went up the road to see if it was a lack of air issue.

I pulled intake off turbo no signs of wear or abnormal play.My boost is usually 10-14 depending on how much you push the pedal and the grade.Any helpful tidbits appreciated Thanks

[rjschoolcraft]

Yes, a wastegate shaft can bind up, mine did on the way to the Rendezvous last year. However, you may want to check your catalytic converter. Your symptoms sound like it could be plugged.

[autocrosser]

If you suspect the catlytic converter being plugged just disconnect it at the cat/down pipe connection and it will tell you real quick if things improve. If it's plugged you should be making lots of black smoke on acceleration also.

[d.h.]

Good idea, but I have no catalytic converter as I have 4" with very open muffler.But egt,s are rising quick like there is a restriction of some kind.I would assume this would also affect boost? I removed the boost fooler that goes to the plenium(not sure I spelled right) and boost was slightly worse.Without boost fooler I used to get at least 6lbs.It won,t muster more than 3 right now. :(

[d.h.]

I checked my wastgate. When I move lever I hear a noticable differance in exaust sound,which would indicate it,s working.Idid however notice minimal suction on solenoid line. I just replaced solenoid and there are no leaks in line.I would sure like to solve this low boost as I,ve been doing a lot of 200 mile rounders lately as my father has been ill. I would really appreciate a remedy or some useful imformation to remedy this problem.I hate going to dealerships when you have add ons! Thanks again

[diesel65]

You mentioned that you are getting minimal vacuum, I would suspect that the vacuum pump is bad.
You should get a vacuum guage and measure it going into the solenoid, you should get over 20 inches of vacuum, then with the solenoid hooked up you should get about 15 inches at the wastegate.

[d.h.]

William, would this cause low boost and high egt,s? I wired wastegate open with no results.Truck just feels like something is holding it back.I,m mechanicly inclined just don,t have that much experiance with the technical stuff. Thank-you

[freddys]

You will need to wire the wastegate closed to make any boost.

[rjschoolcraft]

Check the vacuum pump by measuring vacuum before the wastegate solenoid. Do a search here and you'll turn up lots of information on the subject.

[eracers999]

Fuel filter. ???????

Kent

[Turbine Doc]

Ditto on fuel filter along with vac and WG sol checks, also check that lift pump is delivering fuel to the IP in requisite ammount

[d.h.]

Thanks for responces.I meant wired shut with regards to wastgate.Brain fart!!.The truck runs smooth.Just feels like there,s no turbo.Can,t see much black smoke when I lay into it.Just no boost.I will pick up vaccum guage tomarrow.With wastegate wired shut should this not improve boost? Is vaccum for brakes not supplied by same pump?I,m scraching my head on this one. I will also replace fuel filter just in case.The engine hasn,t missed a beat but sounds like its being held back

[d.h.]

Scartch that bit about vaccum for brakes :rolleyes: I should know as having spent so long under and over that engine.

[Scooby]

I wonder about fuel. With low boost and correct fuel, you should get lots of black smoke due to insufficient oxy to burn all the fuel.

[d.h.]

Well it appears it was vacuum pump after all.I wired waste gate up again and low and behold boost.I guess I didn,t drive far enough last time.Thanks for all the help