Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
> Sputter/cut out at high RPM, is it the distributor?
Groosh
post Nov 23 2017, 12:03 PM
Post #1


Member
**

Group: Members
Posts: 50
Joined: 21-October 11
From: Dexter, MI
Member No.: 13,702
Region Association: Upper MidWest



Happy Thanksgiving!

I'm getting a cut out at higher RPMs but it pulls well. I currently run Hot Spark on the original dizzy and the fuel pressure is solid.

I have oiled the distributor with some results but before I go buy a new one, I wondered if there is something else I might try.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rhodyguy
post Nov 23 2017, 12:06 PM
Post #2


Chimp Sanctuary NW. Check it out.
***************

Group: Members
Posts: 22,042
Joined: 2-March 03
From: Orion's Bell. The BELL!
Member No.: 378
Region Association: Galt's Gulch



Is there a rev-limiting rotor in the distributor?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Groosh
post Nov 23 2017, 12:08 PM
Post #3


Member
**

Group: Members
Posts: 50
Joined: 21-October 11
From: Dexter, MI
Member No.: 13,702
Region Association: Upper MidWest



QUOTE(rhodyguy @ Nov 23 2017, 10:06 AM) *

Is there a rev-limiting rotor in the distributor?


No, it is the standard one.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
mgphoto
post Nov 23 2017, 01:40 PM
Post #4


"If there is a mistake it will find me"
***

Group: Members
Posts: 1,330
Joined: 1-April 09
From: Los Angeles, CA
Member No.: 10,225
Region Association: Southern California



Oil could be a problem.
Best to use Bosch high temp dizzy grease.
FI points are low voltage, they don't burn impurities off, causes the engine to stutter.
The Bosch stuff stays put when hot.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Groosh
post Nov 23 2017, 01:44 PM
Post #5


Member
**

Group: Members
Posts: 50
Joined: 21-October 11
From: Dexter, MI
Member No.: 13,702
Region Association: Upper MidWest



QUOTE(mgphoto @ Nov 23 2017, 11:40 AM) *

Oil could be a problem.
Best to use Bosch high temp dizzy grease.
FI points are low voltage, they don't burn impurities off, causes the engine to stutter.
The Bosch stuff stays put when hot.

I'll clean it up but would this still be a problem with the Hot Spark electronic ignition?

User is offlineProfile CardPM
Go to the top of the page
+Quote Post
timothy_nd28
post Nov 23 2017, 03:41 PM
Post #6


Advanced Member
****

Group: Members
Posts: 2,298
Joined: 25-September 07
From: IN
Member No.: 8,154
Region Association: Upper MidWest



Clark had a similar issue. I texted him instructions that's not in this thread but look at post 6 for his conclusion
http://www.914world.com/bbs2/index.php?sho...=317471&hl=
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
oakdalecurtis
post Nov 23 2017, 06:45 PM
Post #7


Oakdalecurtis
***

Group: Members
Posts: 1,310
Joined: 5-June 15
From: Oakdale, Ca
Member No.: 18,802
Region Association: Central California



If it’s fuel injected, check the trigger points in the dizzy.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
Groosh
post Nov 23 2017, 07:13 PM
Post #8


Member
**

Group: Members
Posts: 50
Joined: 21-October 11
From: Dexter, MI
Member No.: 13,702
Region Association: Upper MidWest



QUOTE(timothy_nd28 @ Nov 23 2017, 01:41 PM) *

Clark had a similar issue. I texted him instructions that's not in this thread but look at post 6 for his conclusion
http://www.914world.com/bbs2/index.php?sho...=317471&hl=


Thanks Tim! It looks like heat may be my problem. I did feel like the car didn't skip as much early on in this colder weather. I'll try the arctic silver between the plates. There are probably no more than 50 miles on the Hot Spark.

Do you think the coil and ballast resistor are also needed?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
timothy_nd28
post Nov 23 2017, 09:19 PM
Post #9


Advanced Member
****

Group: Members
Posts: 2,298
Joined: 25-September 07
From: IN
Member No.: 8,154
Region Association: Upper MidWest



He has a pointless module installed inside the distributor, also this injection system doesn't use trigger points. (IMG:style_emoticons/default/beerchug.gif)

Clark had a similar issue where his hot spark would start whacking out above 3000 rpm. I had him use a timing light attached to a random plug wire, and had him stare at this timing light as he manipulated the throttle cable. I had him repeat this test for every plug wire. I do believe his hotspark did fail due to a heak soak issues, either way it failed. If you repeat the test and see the same thing, your hotspark module has failed too.

I've become a believer with this group buy 123 distributor. It is a investment, but I think it is money well spent vs buying another hotspark module.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
malcolm2
post Nov 23 2017, 09:29 PM
Post #10


Advanced Member
****

Group: Members
Posts: 2,729
Joined: 31-May 11
From: Nashville
Member No.: 13,139
Region Association: South East States



Yes Tim_ND helped me. The timing light showed the cut out. I put it on each spark plug wire and all 4 cut out.

Go to the hot spark web site. They have documents and tests. It seems to be voltage that got me. Guess it is heat from voltage. I bought their coil and their ballast resistor. I still got over 14 volts. They want under 13.7. I got a 5 ohm br at napa. Slightly better voltage readings at high rpm, but not idle. Still 14. Put their br and the napa in series and still have too high voltage at 950 rpm.

I have just left it with the new coil, new hot spark and the napa BR. And a spare hot spark in my trunk. The 1st hs module made it 38000 miles. during that time i did replace the voltage regulator. Did not know i should check the HS voltage. The HS comes with a pack of the cool goo stuff. Did you install it under the HS?

Iam not much help. Good luck.

Clark
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
timothy_nd28
post Nov 23 2017, 09:47 PM
Post #11


Advanced Member
****

Group: Members
Posts: 2,298
Joined: 25-September 07
From: IN
Member No.: 8,154
Region Association: Upper MidWest



Your input does help, it opened my eyes to a shitty design flaw with the hotspark module. I know it's a cheap knock off to the better pertronix module, but why would they design it for max voltage of 13.7v? (IMG:style_emoticons/default/screwy.gif)

I've been having a intermittent issue with my own 914, I haven't had much time in diagnosing it yet but I think it is ignition related. It's acting very similar to what you and Clark experienced. This is why I think it may be time to jump ship and abort the Chinese hotspark module and switch to the 123 dizzy. There are some very good reviews, and I like the option of tweaking the timing curve through my phone. This could be useful for different octane fuels or modern fuels riddled with ethanol.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Groosh
post Nov 24 2017, 08:16 AM
Post #12


Member
**

Group: Members
Posts: 50
Joined: 21-October 11
From: Dexter, MI
Member No.: 13,702
Region Association: Upper MidWest



Thanks everyone!
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
malcolm2
post Nov 25 2017, 06:36 AM
Post #13


Advanced Member
****

Group: Members
Posts: 2,729
Joined: 31-May 11
From: Nashville
Member No.: 13,139
Region Association: South East States



Since i have a fresh module installed and a spare in the trunk, i'll put the new disty on the wish list and see how long i can make it in this set up. If 30000 + per module is my number, I'd say I might have 5 years to save up for one. And i can test the voltage often to see if it increases.

I like the idea of a new disty too. I just replaced the coil packs on my boar. It runs and starts like a dream.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 29th March 2024 - 09:51 AM