Question about Porsche 944
Please read through once and then perhaps go back again and take a couple notes.I believe you would get more out of it as I had a couple of different options to respond about as you will see. I believe the fuse is not likely the cause because when you crossed the ground and the hot on the starter,which is a direct line from the fuse and it turned over,but you bypassed the start relay.You do mention the ignition relay so I am not sure if it is just a misunderstanding of the component name?When you turn the key,you should hear a clicking noise,usually under the hood,although I have never worked on a Porsche,that is where it normally is.If you really are talking about the ignition relay and not the starter relay,call a dealer and they will tell you where the start relay is free normally.However,the start relay and the ignition switch are a direct input to the PCM(basically a start system computer known as Powertrain Control Module)but the start relay has to be good to enable the solenoid,which if either of those 2 were not working properly,would directly result in the whole fuel system being disabled.That is a very basic control system for just about all cars.If you are 100% sure the fuel pump is working,that means everything I mentioned into the PCM is good and activates the fuel pump relay to send fuel from the pump.Even though the fuel pump is making noise,it could be doing just that,just making noise.There is also 1 relay left before you go trying to test the fuel pump.It is called an auto-shutdown relay.It gets power from the fuel pump relay and an input from the PCM.If it is bad,it controls the fuel injectors so it also would not deliver fuel.To sum it up,if your fuel pump is working and delivering fuel for sure,then the starter solenoid,starter,ignition,and brake pedal sensor(forgot to mention this one,also required for start) are good.PCM should be good leaving the fuel pump,fuel relay,and auto-shutdown relay.Obviously,the 2 relays will be easier to check.If you have questions or need clarification,please reply here and I will get an autolink to your post.Can you read a schematic?
Good luck! Greg
Posted on Sep 27, 2010
Your car has a clutch switch if it's a standard and a park neutral switch if it's a automatic. The automatic it's in the console with a rod connected to the shifter, Knock the shifter to the side too hard, ( jump in the car and push the shifter sideways) and the rod can pop out. With the cover off just pop it back in. On the standard shift the switch is on the clutch pedal and you can break the wire or the plug or the switch it's self with your big feet. The carpet can bulg up under the pedal not letting you pust it down all the way. It in doubt about either switch there's just the two wires cross them and it'll start no matter ( just be careful as the reson for the switch is to keep you out of a wreak) Lets say your still out to passture and the switch is good Turn to start and the test light lights at both sides of the switch the wire at the starter ( the one small wire) comes hot in the startt position and you add power at this wire and theirs still no reaction, with this wire hot ( jumper wire , someone holding the key to start) rap on the starter with a hammer, I didn't say nail it) still no good and the big wire from the battery is hot ( battery cable going to the starter is clean and good, then the starter is bad. Have the parts store test it before you buy the new one as if it's good you missed somewher in the story I just told. 10 volts or more at the starter with the key heald at start and it'll start if it's going to/
Posted on Sep 27, 2010
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
Jan 24, 2016 | Porsche Cars & Trucks
Apr 12, 2014 | Cars & Trucks
Feb 14, 2011 | 1987 Porsche 944
Dec 16, 2010 | 1985 Porsche 944
Aug 16, 2010 | 1991 Porsche 944
Apr 17, 2010 | 1984 Porsche 944
Apr 12, 2010 | 1986 Porsche 944
Jan 17, 2010 | 1984 Porsche 944
Jun 04, 2009 | 1987 Porsche 944
Sep 10, 2008 | 1987 Porsche 944
Aug 06, 2017 | Porsche Cars & Trucks
135 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: