Why won't it stay running?, 1973 2.0 |
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Why won't it stay running?, 1973 2.0 |
nomedulla |
Nov 18 2013, 07:34 PM
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#1
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
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r_towle |
Nov 18 2013, 07:43 PM
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#2
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Valve are now to tight.
It happens, sorry, but do it again. My 911 was the same way when I bought it. It's important that you actually hear the tappets, it means they are set correctly. Valves too tight will make the car run as you explained. |
nomedulla |
Nov 18 2013, 08:03 PM
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#3
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
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76-914 |
Nov 18 2013, 08:22 PM
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#4
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Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,613 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California |
Do it before you drive it again. Better too loose than tight. Too loose won't harm anything but your ego. Too tight makes your check book open.
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gothspeed |
Nov 18 2013, 08:41 PM
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#5
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
Do it before you drive it again. Better too loose than tight. Too loose won't harm anything but your ego. Too tight makes your check book open. +1 .... (IMG:style_emoticons/default/smash.gif) |
nomedulla |
Nov 19 2013, 04:17 PM
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#6
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
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boxsterfan |
Nov 19 2013, 04:59 PM
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#7
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
Do it before you drive it again. Better too loose than tight. Too loose won't harm anything but your ego. Too tight makes your check book open. +1 .... (IMG:style_emoticons/default/smash.gif) OK, I have readjusted the rocker arms again, checked the timing, etc., and it still will not idle without "butterflying" the throttle. What next? I have pulled the plugs, they are clean and gapped. Checked all the hoses and connections, again. Should I test the AAR/Throttlebody readings? Is there anything else that would affect the air/fuel/idle ratio? It runs well when accelerated, but will not stay consistent after a few moments at higher RPM. I have a Petronix unit. I pulled the distributor and checked the gap from the pickup to the magnet...it is at .003, as the manufacturer recommends. I am not Mr Goodwrench, but I have been tinkering with VW/Porsche 914s since my teenage years... 69VW being my first car, 74 2.0 my second. Is this when engine is cold? Could be stuck closed AAR. My AAR had the exact opposite at cold start....idles up around 1800 until then warmed up and then goes to 3000 RPM because the AAR doesn't close (stuck open). I've got a new refurb one to install, but my short term workaround every morning has been to get out and plug the input to the aair vac line (after which idle immiediately drops to 950). Voila!! |
nomedulla |
Nov 19 2013, 05:43 PM
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#8
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
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Jeffs9146 |
Nov 19 2013, 05:46 PM
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#9
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Ski Bum Group: Members Posts: 4,062 Joined: 10-January 03 From: Discovery Bay, Ca Member No.: 128 |
Are you adjusting the valves when the motor is cold or warm?
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nomedulla |
Nov 19 2013, 06:05 PM
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#10
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
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Cap'n Krusty |
Nov 19 2013, 07:25 PM
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#11
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
Have you read my tutorial in the classic threads?
The Cap'n |
Jeffs9146 |
Nov 19 2013, 08:12 PM
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#12
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Ski Bum Group: Members Posts: 4,062 Joined: 10-January 03 From: Discovery Bay, Ca Member No.: 128 |
Are you adjusting the valves when the motor is cold or warm? ...without question when they are cold. (IMG:style_emoticons/default/beerchug.gif) Just throwing it out there!! |
nomedulla |
Nov 19 2013, 08:33 PM
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#13
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
Have you read my tutorial in the classic threads? The Cap'n Yes Sir... Will be reference material (IMG:style_emoticons/default/smilie_pokal.gif) |
nomedulla |
Nov 19 2013, 08:35 PM
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#14
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
Are you adjusting the valves when the motor is cold or warm? ...without question when they are cold. (IMG:style_emoticons/default/beerchug.gif) Just throwing it out there!! No worries, I know sometimes the most obvious is something that may be overlooked. Thanks for taking time to review my thread and offer input. (IMG:style_emoticons/default/beerchug.gif) |
turk22 |
Nov 19 2013, 08:45 PM
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#15
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Treetop Flyer Group: Members Posts: 735 Joined: 27-July 12 From: Cincinnati OH Member No.: 14,725 Region Association: Upper MidWest |
did you do anything else in conjunction with the valve adjustment? like new plugs, oil change etc. ?
It may be something that came loose while you were in the engine compartment. |
r_towle |
Nov 19 2013, 08:50 PM
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#16
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Do you have the knob on top of the ECU to adjust your idle mixture?
This happens only when cold? Check your CHT wiring, make sure it tight and you did not damage it while doing the valves etc....it happens. Umm, Plugs, all of the FI plugs, pull them and reset them. Can you affect the idle by setting the idle air bypass screw? Does the do anything? If not, there are other things to look at. If that works, it's most likely AAR... |
nomedulla |
Nov 20 2013, 07:20 AM
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#17
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
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nomedulla |
Nov 20 2013, 07:23 AM
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#18
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NOMEDULLA Group: Members Posts: 32 Joined: 22-March 06 From: SWFLA Member No.: 5,759 Region Association: South East States |
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r_towle |
Nov 20 2013, 08:11 AM
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#19
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
well, the sudden change in morning/ overnight temps may have affected what you are dealing with.
Pull the AAR out. Ground it at the body. Add power to the red lead. Does it open all the way? Does it close all the way? Even before that... Two fuses on the engine compartment relay...still good? I dont recall the wiring diagram with respect to the Temp Sensor and the AAR, but they are right next to each other in the wiring loom.... Did you jostle that AAR connection in some way? Rich |
r_towle |
Nov 20 2013, 08:15 AM
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#20
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
I always do these type of triage things with a few assumptions.
I did something wrong.,.. The simplest thing is typically the issue. So, what did you touch, back track. If you pulled out the spade to solder...what else did you disturb in the process. Its not like there is plenty of slack in that harness. You would have disturbed (possibly) all the Injector grounds (passenger side, under the plenum, top case bolt near rear) AAR Distributor EFI trigger points Coil wiring I think that is all that is over there....but you may want to just follow the wiring loom for the EFI and check every connection, reseat all of them, etc. |
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