Trigger points were probably the problem, Debris behind TP arm Options

[oakdalecurtis]

Stock 76 2.0, owned it a long time. Engine ran good sometimes, and then sometimes it would begin to miss intermittently upon hard acceleration. Checked tune, no vacuum leaks, changed spark plugs and wires and replaced throttle position sensor board. No help. I took it to my best 914 mechanic, he said fuel injectors were not firing correctly and recommended I replace the trigger points under the distributor. A member here sent me some slightly used TPs. I finally got around to installing them last weekend. I removed the dizzy (btw, if you only take off the 13 mm hold down bolt and carefully remove the distributor, it goes right back in without changing the timing), to make the TP change. Upon close inspection of the old trigger point plate, I noticed what looked like a small piece of phenolic like debris behind one of the trigger point arms. I don't know if this was the problem all along, but I do know that when I put in the replacement set of TP's and put it all back together, the engine has NEVER run so perfectly. The motor pulls hard from the get go, even when cold, and never misses a cylinder any more. Thank you Bruce914 for sending me the TP's, what a difference they made!

[Tom_T]

Glad you got it figured out Curtis.

Those TPs have a replacement schedule by miles, but then age is a factor too - especially with lower mile driven 914s like yours, where it's easy to loose track of when they were replaced last.

If you can locate a set of new or NOS ones for your parts stash, do so before they're NLA & all gone! I got some a couple of years ago from Porsche, but don't know their current availability.

Rich Bontempi at HPH (High Performance House) in Redwood City may have some, & can tell you the factory recco'd replacement schedule for them.

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Tom
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[pbanders]

FWIW, NOS trigger contact points are going for about $400 on eBay these days. You might want to consider cleaning yours, and buying Norbert's adjustment tool to adjust worn points back to proper operation.
http://www.914world.com/bbs2/index.php?sho...norbert+trigger

[oakdalecurtis]

Glad you got it figured out Curtis.

Those TPs have a replacement schedule by miles, but then age is a factor too - especially with lower mile driven 914s like yours, where it's easy to loose track of when they were replaced last.

If you can locate a set of new or NOS ones for your parts stash, do so before they're NLA & all gone! I got some a couple of years ago from Porsche, but don't know their current availability.

Rich Bontempi at HPH (High Performance House) in Redwood City may have some, & can tell you the factory recco'd replacement schedule for them.

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Tom
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Hi Tom, thanks, what's NOS?

[Frankvw]

NOS = New Old Stock
old but new. Laying around unused for many years.
Good your issue got sorted. Interesting to read.

[oakdalecurtis]

NOS = New Old Stock
old but new. Laying around unused for many years.
Good your issue got sorted. Interesting to read.

thanks! I will save my old TP's I removed, they may be actually be fine and it might have always just been the debris behind one of the arms causing all my intermittent misfire issues. I don't drive the car that much per year anyway, just local trips around town.
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