Poor running SC. I cannot seem to figure this one out. - Page 3 - Dorkiphus.net
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  #21  
Old 09-08-2010, 02:04 PM
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While hauling Dr. K around teaching him a new line I got a miss. Then another and another. It was the end of the second run and I planned an early exit anyway so I put it on the dolly and came home. When I tried to start to off load from the dolly the car would not fire. Opened the trunk, pulled the electric panel cover and found the red fuel relay had eased itself away from the socket some. Re set it and everything fine now.

Steve, replace the relay. You can use a black one if that is all you have and if that fixes it order a new red one. While you are doing that check the socket and see if one of the pins is discolored. If so, you have found your problem.

ARF
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  #22  
Old 09-08-2010, 02:58 PM
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Steve,
If that's it, I've got TWO of those red relays (brand new) and you're welcome to one of them.
Peter
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  #23  
Old 09-08-2010, 06:21 PM
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Quote:
Originally Posted by arob View Post
(Tracking this thread) - I encountered similar problem this past weekend at VIR. Warm up lap of the last session on Sunday, coming up the esses, my car just started running like shit, eventually cutting itself off at South Bend. I was able to coast down the hill, and park it next to the Oak Tree flag station.

When I got towed back into the paddock, I started it long enough to get it onto the trailer. Sounded like shit, RPMs jumping all over the place, and eventually cutting off. Riley took a listen to it for about 15 seconds, and thinks it's a vacuum leak.

Monday morning, I pulled the air box off and noticed that the pop-off valve had cracked off at one end of the spring hinge (non-fixable). Will be ordering a new one.

Fairfax Jim came over and we tested spark and fuel pump, which turned out fine. Started it back up again, and after about 10 seconds of smoke, it started running fine again. Took it around the block, and all seemed well.

I'm still not sure what went wrong (besides pop-off valve), and am not totally sure it fixed itself.

I've got 3 more events until the end of the season, and I'm hoping that it'll survive.
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  #24  
Old 09-08-2010, 08:51 PM
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Originally Posted by tdatk View Post
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Not too soon, Timmy.

Started it up again after work, and it's idling better, but now the tack is ALL OVER the place. Leaving for the Outer Banks on Friday, so I'll address all over again when I get back.
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  #25  
Old 09-08-2010, 09:49 PM
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Originally Posted by arob View Post
Not too soon, Timmy.

Started it up again after work, and it's idling better, but now the tack is ALL OVER the place. Leaving for the Outer Banks on Friday, so I'll address all over again when I get back.
Call when you get back. I deal with disappointing results every day, it's my thankless job, someones got to do it.
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  #26  
Old 09-16-2010, 08:25 PM
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Quote:
Originally Posted by Vicegrip View Post
+1 I don't understand the confusion here. You have a group of issues that can all stem from the MSD. You need to swap it out with a known good one. A malfunctioning MSD can cause spark timing shifts in addition to dropped spark pulses.

Got the unit back from MSD/Autotronics this evening. They found the unit defective and have a whole bunch of test areas. Tach output was the area that failed as well as rev limiters, but I suspect they checked fail instead of n/a, due to some other writing on the test sheet.

For the EEs in the house (can you translate), the repair work said:
Replaced 2.2 uF TANT unstable capacitor
Update SPP70N10L transistor.
RN330K ohm resistor unstable
Checked with tachmeter


So I'm pleased that they found something wrong. Now I need to hook it all up again and report back.
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  #27  
Old 09-17-2010, 09:06 AM
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Whats there to translate? Replaced capacitor, mosfet, resistor. Tested.
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  #28  
Old 09-19-2010, 07:02 PM
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Hooked it all up to the car and did a 40 miles test loop. All systems seem to be green. What a long drawn out PITA this was.
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  #29  
Old 09-19-2010, 08:01 PM
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Hooked it all up to the car and did a 40 miles test loop. All systems seem to be green. What a long drawn out PITA this was.
That's great news.
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