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  #16  
Old 11-09-2005, 02:43 PM
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Manarius Manarius is offline
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Quote:
Originally Posted by rufus
Mine surges too. Always has. I think it's the anti-matter pulse drive kicking in.
Sure? I always thought it was the Ion engine
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  #17  
Old 11-09-2005, 03:11 PM
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A dirty or faulty TPS will also cause slight surging. People usually don't notice until they use the cruise because no one keeps the pedal steady enough to notice it.

Doug
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  #18  
Old 11-09-2005, 03:35 PM
oab_au oab_au is offline
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More to do with the gearing.

This surging has more to do with the gearing that the car has. Mine has standard gearing, but if it is in third, it will surge.

The way it works is, the Cruise vacuum motor pumps vacuum to the throttle diaphragm to open the throttle, the engine speed increases, the Cruise Comp. looks at the road speed to check if it is at the specified range, if ok, it holds it. If not it will adjust the vacuum to achive the specified range.

All this is timebased, the set and checking intervials is fixed, to suit the 'rate of change' that the car will respond to the vacuum change, hence the gearing the car has. If the gearing is lower, the 'rate of change' will be quicker, than the timebase setting, so the speed rises faster than the vacuum setting, the Cruise sees this, so it reduces the vacuum, which drops faster, so it goes back and forwards, causing the surging.

The fix for this is to reduce the engines reaction speed, so that it is more in line with the timebased setting, by restricting the vacuum line to the diaphragm. The type of clamp used on air lines used on fish tanks, or medical line equipment, can be used on the vacuum line, to adjust the flow to remove the surging.

Harvey.
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  #19  
Old 11-12-2005, 05:20 AM
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Quote:
Originally Posted by oab_au

The fix for this is to reduce the engines reaction speed, so that it is more in line with the timebased setting, by restricting the vacuum line to the diaphragm. The type of clamp used on air lines used on fish tanks, or medical line equipment, can be used on the vacuum line, to adjust the flow to remove the surging.

Harvey.

LOL, now that's a technical fix...I love it. Off to the pet store I go!

Thanks mate.

Ali
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  #20  
Old 12-01-2005, 10:21 PM
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I fixed about 95% of the surging during cruise control. Turns out that at some point during maintenance to my car, the cruise control cable and the throttle cable got switched on the throttle body. The cam on the throttle body for the cruise control system is larger and this appears to be affecting how the cruise control works. Could be that the larger cam causes less change in the throttle position, or maybe the cruise control system is sensitive to the pulling force required to open the throttle with the larger cam. Anyhow, its nice to have a non-surging cruise control again.
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