"full throttle" problems

[Silver Turbo]

When I floor the accelerator, after one or two seconds suddenly my 480 turbo sort of shakes (I don't really know how to describe what happens) or rather jolts. Is this normal (for example due to too high pressure in the turbo or something like that)? <p>Volvo for life, 480 for eternity.</p><i>Edited by: <A HREF=http://pub32.ezboard.com/bvolvo480.show ... rbo>Silver Turbo</A> at: 1/21/03 10:12:33 pm<br></i>

[David Thornber]

If the boost pressure has been modded, it could be an overboost limiter cutting in. If I remember rightly this cuts the ignition at a certain boost pressure (don't know what the pressure is) to protect the engine from damage. When the boost pressure drops, the ignition is enabled again. When I fiddled with mine I had the same symptoms when the boost gauge reached the top of the yellow section of the gauge.<br>What does your turbo gauge read under full throttle?<br> <p></p><i></i>

[dan]

I boost into the red with no problems (about 11 psi). I had a similar hesitation/jolt or misfire. Turned out to be a worn distributor cap/rotor arm not providing a sufficient spark under load. Replace it, and leads, sparkplugs if you haven't already. <p></p><i></i>

[Silver Turbo]

Yeah it must be that because it jolts towards top of yellow and I made no modifications whatsoever. <p><!--EZCODE ITALIC START--><em>Volvo for life, 480 for eternity.</em><!--EZCODE ITALIC END--></p><i></i>