 On Topic: Missing above 3k rpm, under load only |
|
|
|
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. |
|
|
| djm914-6 |
  Apr 6 2004, 08:54 PM
Post
#1
|
|
Happiness is: Getting on the road  Group: Members Posts: 1,864 Joined: 6-February 03 From: Burlington MA Member No.: 248 Region Association: None  |
So, I'm cruising down the road and step on the gas to pass a few cars but the car doesn't go anywhere. Instead of the usual vrooom to red line, I gat a bunch of flat sounding sputters. When I let the car cruise, it runs fine. Of the line is good also untill I reach ~ 3200 RPM. No mater what I do, I can't go past 4k, even nursing it.
I'll see what happens tomorrow when I put the muffler caps back on, but I can't see how 3 exits would run worse than one exit. What should I be looking for? My boss thinks plug wires, but he's a Healey guy so of couse he'd guess electric faults. I'm looking for some real basic pointers here is you got 'em. I'd love to fix this one myself. Thanks All, (IMG:style_emoticons/default/pray.gif) |
   |
 
|
  |
Replies(1 - 11)
| campbellcj |
Apr 6 2004, 11:00 PM
Post
#2
|
|
I can't Re Member Group: Members Posts: 4,550 Joined: 26-December 02 From: Agoura, CA Member No.: 21 Region Association: Southern California 
|
My first guess(es) would be ignition related, just like your Harley friend (IMG:style_emoticons/default/smile.gif)
Timing, dwell/points and plug wires... check the simple stuff first! Assuming the car is carbed it might potentially be an issue with the idle-to-main transition i.e. clogged main jets or other carb farkups? |
|
|
|
| Curvie Roadlover |
Apr 7 2004, 04:06 AM
Post
#3
|
|
Two trunks are better than one! Group: Members Posts: 2,025 Joined: 29-December 02 From: Southeast Michigan Member No.: 42 |
Also could be the throttle position sensor
|
|
|
|
| ArtechnikA |
Apr 7 2004, 04:45 AM
Post
#4
|
|
rich herzog Group: Members Posts: 7,390 Joined: 4-April 03 From: Salted Roads, PA Member No.: 513 Region Association: None |
QUOTE(Curvie Roadlover @ Apr 7 2004, 02:06 AM) Also could be the throttle position sensor Dave's car has two throttle-position sensors, and they're both triple-throat Weber's :-) |
|
|
|
| Tom Perso |
Apr 7 2004, 06:24 AM
Post
#5
|
|
Crazy from the Cold... Group: Members Posts: 647 Joined: 8-August 03 From: Kalamazoo, MI Member No.: 1,003 |
I would thing ignition as well... Check the cap for misfiring (burn marks), wires, plugs, etc...
I would have a hard time believing that you lost all 6 transition circuits on your webers at the same time... Ignition... (IMG:style_emoticons/default/wink.gif) Later, Tom |
|
|
|
| jtf914 |
Apr 7 2004, 07:10 AM
Post
#6
|
|
Member Group: Members Posts: 428 Joined: 31-December 02 From: Burlington, CT Member No.: 58 Region Association: North East States |
(IMG:style_emoticons/default/agree.gif) Sounds like ignition.... Have you adjusted the timing lately??? Make sure you tightened the distributor back.....
|
|
|
|
| djm914-6 |
Apr 7 2004, 08:32 AM
Post
#7
|
|
Happiness is: Getting on the road Group: Members Posts: 1,864 Joined: 6-February 03 From: Burlington MA Member No.: 248 Region Association: None |
I reattached the caps over the middle two exhaust exits for a quite(er) ride this morning. What do you know... no problems! The car pulled strong to redline each and every time I tried it.
So, how does this effect the engine? Mixture? |
|
|
|
| ArtechnikA |
Apr 7 2004, 09:17 AM
Post
#8
|
|
rich herzog Group: Members Posts: 7,390 Joined: 4-April 03 From: Salted Roads, PA Member No.: 513 Region Association: None |
QUOTE(djm914-6 @ Apr 7 2004, 06:32 AM) So, how does this affect the engine? Mixture? yup - i always had to run bigger main jets with open exhaust. intake and exhaust has to be a balance. you could probably run bigger mains (or smaller air correction) if you wanted to keep the free-er flowing exhaust... |
|
|
|
| mskala |
Apr 7 2004, 09:43 AM
Post
#9
|
|
R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None
|
Distributor advance is stuck or can't get past a certain point.
Easy to check with timing light. |
 |
|
| cary |
Apr 7 2004, 06:07 PM
Post
#10
|
|
Advanced Member Group: Members Posts: 3,900 Joined: 26-January 04 From: Sherwood Oregon Member No.: 1,608 Region Association: Pacific Northwest
|
Ground strap on the distributor plate is broken. Once you get to a certain point in the curve it looses contact. And you go to ZERO .............no ignition.
|
|
|
|
| 94teener |
Apr 7 2004, 06:50 PM
Post
#11
|
|
Member Group: Members Posts: 209 Joined: 6-February 04 From: Jacksonville, FL Member No.: 1,636 |
Your engine may be suffering from fuel starvation under load (can't pump, can't get the pressure). Check main line fuel filter(s), especially the fuel screen in the fuel tank, actually the screen is attached to the fuel outlet fitting on the tank.
Phil |
|
|
|
| mskala |
Apr 7 2004, 07:09 PM
Post
#12
|
|
R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None
|
QUOTE(djm914-6 @ Apr 7 2004, 09:32 AM) I reattached the caps over the middle two exhaust exits for a quite(er) ride this morning. What do you know... no problems! The car pulled strong to redline each and every time I tried it. So, how does this effect the engine? Mixture? I don't think it's going to be such a huge difference as you were describing, just from a change in backpressure. I think you have an intermittent. |
|
|
|
|
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 17th June 2024 - 09:34 AM |
Invision Power Board
v9.1.4 © 2024 IPS, Inc.