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View Full Version : Car Sputters Under Boost!!

JordanButter
October 12th, 2006, 11:20 PM
Recently my 98 GSX has started sputtering under boost I first noticed it happening on 50% throttle between 3k-5k rpms. Now it seems to be all the time, the turbo has maybe 10k miles on it and my boost gauge shows normal boost. I have tried putting my AFC back to +/- 0 and still nothing. Is there a chance it heavy shaft play, and how can I check/repair this? Thanks. Also I have been told that it is the plugs and wires. Well they are new plugs and fairly new wires that I checked and to make sure they're ok.
rlarsen
October 13th, 2006, 01:18 AM
Check coil pack and plug gap. New wires != good wires.
Zeppelin
October 13th, 2006, 06:36 AM
Also try a boost leak test.
JordanButter
October 14th, 2006, 07:13 PM
Ok I did a leak test and I can hear a leak up front but I can't find it. It seems like the LICP gasket, EX Mani gasket, or the EX Mani it self. Is there anyway to tell where a leak is other than the sound it self? Also how can I get the exhaust manifold off cause the bolts are really stuck not to mention I don't know esacally which ones to undo?
yokotabrat
October 14th, 2006, 07:41 PM
Ok I did a leak test and I can hear a leak up front but I can't find it. It seems like the LICP gasket, EX Mani gasket, or the EX Mani it self. Is there anyway to tell where a leak is other than the sound it self? Also how can I get the exhaust manifold off cause the bolts are really stuck not to mention I don't know esacally which ones to undo?

You can get a spray bottle and put some water and soap in it. Spray the area that you suspect is leaking, and if it is, it'll bubble.

Exhaust mani is held on by 9, I think, nuts to the cylinder head and 4 large bolts that bolt to the turbine housing of the turbo. You might need a decently sized rachet to get the turbo/manifold bolts off as they usually stick themselves in fairly well. You'll also probably need to remove the power steering pump to get access to one of the nuts in the bottom right. You really shouldn't have a leak that shows up here with a standard boost leak test, however.

Hope this helps.
XakEp
October 14th, 2006, 09:37 PM
Got a MAF-T?
JordanButter
October 14th, 2006, 11:29 PM
No I don't have a MAF-T I have the stock MAFS.
Wazzelby
October 17th, 2006, 03:08 PM
I'm leaning toward plugs and/or wires as well. if even 1 plug or wire is bad, it can reak havok on your cars driveability.