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#1
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I was wondering if anyone has any insight or suggestions. I went to go start up my car to make sure everything was in order. Engine cranks, nothing. Tach isnt bouncing at all. This leads me to believe the reference sensors are bad, but they were recently replaced earlier this year. The connectors were all taped up, so I peeld back the tape to make sure everything was connected, and it looks like the PO cut off the harness end of the connector to do something and then attaced spade terminals to plugh the wires in to the sensor. Anyways, its all hooked up correctly as far as I can tell and the terminals are making a good connection. I need to fix this ASAP. My cars new owner is supposed to pick the car up next week, and Id rather not have to tell him that its not running. ANy help would be appreciated!
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Jason 88 924S "SE" |
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#2
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Have you done the normal checks -- fuel, spark, timing?
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#3
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Check connections at the distributer cap; remove and replace the wires.
Also check the DME relay; a common issue. Sometimes removing and replacing will get it functioning again.
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- Tony P. Currently - 1984 944 SP2 racer - 1977 911 KM Special vintage racer - 2000 Boxster S (now mine) - 1995 993 (garage queen) - 2007 Cayman S (wife's track beast) - 2017 F350 (tow monster) - 2018 Jeep Wrangler - 1982 911 Targa (resurrection in process) Gone but not forgotten - 1989 944S2 - 1979 RX7 - 1986 944 - 1991 944S2 (in car heaven...) - 2001 Chevy Suburban 2500 (FIL's beast now) - 2012 Cayman R |
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#4
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Does it start if you roll-start it? If so, chech flywheel sensor gap (at least this holds for a 911 engine).
Peter
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Peter (not "Pete") K. 2026 Lucid Gravity Grand Touring (EV Tow Vehicle) 1997 Spec Boxster #671 2016 Cayman S 2016 Toyota Highlander--wife's DD 2017 VW GTI SE (DD) Gone and missed: 2003 Miata ("SM") race car 1992 Miata ("SSM") race car 2009 911 C2S Coupe 2004 Toyota Prius - sold to son's girlfriend 2006 Dodge Durango 2003 Acura MDX 86 Black 911 Coupe race car 86 Gold 911 Targa 82 WineRedMetallic 911 Targa |
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#5
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Take the connector off the DME and test the continuity of the speed and reference sensor from there. The 944 manuals that DR links to in his signature have all the diagrams and pin outs your need. By ohming out from the DME connector, you'll know if the wiring is the issue or not.
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Chris M 1985 911 Carrera with a couple cosmetic only mods 2006 E90 330i 1999 E46 328i |
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#6
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I removed the distributeer cap and wire and reinstalled everything. The car was running the other day so I'm convinced fuel and spark are ok. I took the reference sensor connectors out and other than being hacked up they look ok. Fuel pump relay is new but I swapped for my spare and no dice. Still nothing.
How do I check for continuity? I'm not so good with electrical stuff...
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Jason 88 924S "SE" |
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#7
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LOL
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#8
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Let me rephrase.... The car was running the other day so I think that the fueling is ok. Since the tach is not moving when trying to get the car started, that means that the DME isnt getting a signal from the reference sensor which means that it wont send a signal to fire the coil. It could either be because of a bad sensor not sending the signal, or bad wiring causing the signal to not make it to the DME.
So Im assuming to test continuity between the sensor and the DME Im going to pull the plug off the sensor, and check for voltage while cranking the car there. Then check for the same voltage at the DME? I apologize if this is basic stuff, but like I said electrical stuff isnt something Ive ever really had to do before.
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Jason 88 924S "SE" |
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#9
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You need a volt meter or DVM (digital volt meter).Does volts, ohms, etc... for continuity.
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#10
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Hey Jason,
It figures that your car gives up the ghost as soon as you are ready to sell it... I have a bunch of spare parts for my 924S including a good DME if you need it. Checking the continuity between the DME and ref sensor would be a good place to start. There are a lot of invisible problems that can develop in 20+ year old wiring. My multi-meter has become my best friend.... I figured out my throttle position sensor and MAF problem that way. Next stop would be fuel supply - check pressure. A bad fuel pump or pressure regulator could be the problem. www.clarks-garage.com might have some good advice for you. Hope this helps, Brad
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Brad Somewhere west of I-81 1987 Porsche 924S - track toy 1986 Mercedes 190E-16v - autocross 1994 Volvo 850 race-wagon - Lemons/Chumpcar 2001 BMW 325xi - daily drover 2007 F-150 Lariat Supercrew - tow beast |
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