Author Topic: No Boost  (Read 2634 times)

October 29, 2007, 06:18:53 am

pfai

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No Boost
« on: October 29, 2007, 06:18:53 am »
I have an Air Research Turbo on a 1983 Quantum engine-1.6 TD - not boosting at all .  Fresh engine rebuild, just did Gov mod, pump timing is set @ 1.05 mm, did timing advance mod.   Shows slight vac on boost guage till let off accelerator then gets small pressure surge.  I tightened manifold bolts but were still fairly tight. Turbo has the internal waste gate setup,if ya wana call it that.
  Any help on this would be appreciated.   Thanks,Paul
1986 Samurai 1.6 VW Turbo Diesel

Reply #1October 29, 2007, 12:21:50 pm

pfai

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make that, very late boost
« Reply #1 on: October 29, 2007, 12:21:50 pm »
finally got it out on the road, will boost but not until rpm's are pretty high-no tach-can't be specific      Paul
1986 Samurai 1.6 VW Turbo Diesel

Reply #2October 29, 2007, 03:23:36 pm

subsonic

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No Boost
« Reply #2 on: October 29, 2007, 03:23:36 pm »
Any chance the waste gate may be stuck open?
2009 Jetta TDI Loyal edition, 6-spd. 16V 2.0CR


1985 VW Golf 5-spd, 4-door, 1.6NA  Bought from orig. owner in Savannah with 42,000 miles.
"Making the jump NA to TD" slow but sure.

1980 VW Rabbit LS 5-spd, 4-door 1.6NA almost 450,000miles  RIP

Reply #3October 29, 2007, 03:40:33 pm

Black Smokin' Diesel

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No Boost
« Reply #3 on: October 29, 2007, 03:40:33 pm »
How big is that turbo? Could be turbo lag. I got a k24 and I have next to no boost when there's no load (revving in neutral gets me 3 psi and I can get 20 psi on the road).
91 Passat syncro 1.8T swapped.

Reply #4October 29, 2007, 04:28:22 pm

g-spec

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No Boost
« Reply #4 on: October 29, 2007, 04:28:22 pm »
I have a 1.9TD with a T3 and i cant get the guage to show boost standing in neutral. on the road I hit 9lbs (stock for now) It start building boost just after 2k rpm!!!!

Reply #5October 29, 2007, 04:32:50 pm

Vincent Waldon

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No Boost
« Reply #5 on: October 29, 2007, 04:32:50 pm »
The bigger stock turbos (Garrett T3 and KKK K24) generally don't start to deliver significant boost until the engine is in the 3000 RPM range... depending on the trim of your turbo this may be what you are seeing.

My boost gauge on my T3 start to rise a bit under full load at about 2500 RPM (I've done nothing to the fuel) and I get no boost at all without load.

Can you borrow a tach from someone ??  Gonna be difficult to tell if your turbo is just too big for the engine without some numbers in this area...


Vince
Vince

Edmonton, Alberta, Canada
2001 silver TDI Jetta Malone Stage 1.5 , 2001 blue TDI Jetta SBIII 216s Malone Stage 3, 1970 Bay Window bus

Gone but not forgotten: 1969/1971 Beetles, 1969/1974 Westies, 1979 Rabbit, 1986 TD Jetta, 1992 gas Jetta, 1994 TD Jetta

Reply #6October 29, 2007, 08:03:22 pm

subsonic

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No Boost
« Reply #6 on: October 29, 2007, 08:03:22 pm »
What is the turbo off of?  Do you have the number off the tag?
2009 Jetta TDI Loyal edition, 6-spd. 16V 2.0CR


1985 VW Golf 5-spd, 4-door, 1.6NA  Bought from orig. owner in Savannah with 42,000 miles.
"Making the jump NA to TD" slow but sure.

1980 VW Rabbit LS 5-spd, 4-door 1.6NA almost 450,000miles  RIP