Oh dear-here we go again!, Running rich |
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Oh dear-here we go again!, Running rich |
porschefile2010 |
May 26 2016, 07:49 PM
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#1
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Member Group: Members Posts: 228 Joined: 26-May 11 From: Whangaparaoa, New Zealand Member No.: 13,118 Region Association: Australia and New Zealand |
I needed your help before and now we have a new issue. I have just about had it with the ongoing problems.
Mine is a 75, 2.0 with original FI. I dropped a valve seat and gave it to my garage to repair the head and replace all the valves. It all went back together and fired and ran but only for a very short time as all the cylinders ran rich and fouled the plugs. So my take on this is that it can't be the injectors as they are not all likely to fail at the same time. Perhaps it is something in the system that makes the injectors fire continuously? So could that be trigger points? If you could give me any ideas as to why all the plugs might foul I will start looking at each one until I nail it. Thanks Guys. Richard (IMG:style_emoticons/default/pray.gif) (IMG:style_emoticons/default/pray.gif) |
catsltd |
May 26 2016, 08:31 PM
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#2
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Member Group: Members Posts: 181 Joined: 7-June 15 From: Calgary Alberta Member No.: 18,814 Region Association: None |
I needed your help before and now we have a new issue. I have just about had it with the ongoing problems. Mine is a 75, 2.0 with original FI. I dropped a valve seat and gave it to my garage to repair the head and replace all the valves. It all went back together and fired and ran but only for a very short time as all the cylinders ran rich and fouled the plugs. So my take on this is that it can't be the injectors as they are not all likely to fail at the same time. Perhaps it is something in the system that makes the injectors fire continuously? So could that be trigger points? If you could give me any ideas as to why all the plugs might foul I will start looking at each one until I nail it. Thanks Guys. Richard (IMG:style_emoticons/default/pray.gif) (IMG:style_emoticons/default/pray.gif) My guess its a vacum leak. Head gasket maybe.but for sure something is leaking,or not sealed right. My FI had same problem with fouling plugs,but forgot what caused it. I just got my 1.8L working like a new car,and clutch blew apart. These cars take more patience than anything I have ever done. |
r_towle |
May 26 2016, 08:32 PM
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#3
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Custom Member Group: Members Posts: 24,579 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Sounds like when your valve seat dropped it may have blown too much back pressure through the intake and took out the MPS.
See if the MPS holds a vacuum.... |
porschefile2010 |
May 26 2016, 08:34 PM
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#4
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Member Group: Members Posts: 228 Joined: 26-May 11 From: Whangaparaoa, New Zealand Member No.: 13,118 Region Association: Australia and New Zealand |
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76-914 |
May 27 2016, 08:03 AM
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#5
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Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,505 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California |
Agree with Rich or the MPS is unplugged.
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TheCabinetmaker |
May 27 2016, 08:34 AM
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#6
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Plus one on the mps
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Tbrown4x4 |
May 27 2016, 08:59 AM
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#7
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Senior Member Group: Members Posts: 704 Joined: 13-May 14 From: Port Orchard, WA Member No.: 17,338 Region Association: None |
Sounds like when your valve seat dropped it may have blown too much back pressure through the intake and took out the MPS. See if the MPS holds a vacuum.... Hmmm. There's a thought. I have a spare MPS so I could change that out and see what happens. Thanks Just put a hose on it and see if it holds vacuum. If the diaphragm is blown, the ECM thinks the engine is under full load and goes rich. |
Tom_T |
May 27 2016, 12:42 PM
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#8
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TMI.... Group: Members Posts: 8,318 Joined: 19-March 09 From: Orange, CA Member No.: 10,181 Region Association: Southern California |
Hi Richard,
I just sent you an email on this & the other info. you wanted before. Again for those reading on here, if you've got a shop doing your work for pay who cannot diagnose & fix these issues, then you need a different shop more familiar with 914/411/412/Bus with the 2.0s IMHO! (IMG:style_emoticons/default/dry.gif) I mention the MPS noted above + FPR & ECU + bad rebuilt injectors possibilities, as well as possible problems if that D-jet was used & modified on your prior 2.4 that came on the car. Tom /////// |
Dave_Darling |
May 27 2016, 02:52 PM
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#9
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914 Idiot Group: Members Posts: 14,990 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
MPS would be the first thing I would check, along with its hose.
Fuel pressure would be the second thing. ....Actually, in my car it'd be the other way around, because I have a fuel pressure gauge permanently mounted in the engine bay... (IMG:style_emoticons/default/wink.gif) After that, I'd be looking at the ignition system. --DD |
porschefile2010 |
May 27 2016, 04:19 PM
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#10
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Member Group: Members Posts: 228 Joined: 26-May 11 From: Whangaparaoa, New Zealand Member No.: 13,118 Region Association: Australia and New Zealand |
Thanks to everyone. That'll keep me busy for the weekend. Appreciate all your advice.
R (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/bye1.gif) |
Samuelrocky |
May 27 2016, 11:29 PM
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#11
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Newbie Group: Members Posts: 4 Joined: 22-October 13 From: Coeur d'Alene, ID Member No.: 16,546 Region Association: Pacific Northwest |
The cold start valve malfunctioned on my 73 2.0 which caused extreme rich fuel mixture. Unplugged it and the car ran normally.
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