The Neverending

[eresener]

Went out last night for a cool evening cruise...went great...about a 24 mile rt on a long hwy...was just wonderful. got back home last night and put the car to bed. Today I go out to fire it up ... no go. Plenty of cranking...but nada, nothing as far firing up. WTF...BTW last evening on my cruise I did notice the gas gauge bounce once or twice...this is the only culprit I noticed. Other than this no start...car is running great. Wiring issues have subsided (I hope) but who knows with this car.

[fast924S]

DME RELAY????? GROUNDS???

[SoCal Driver]

Go through the five minute quick test.

Check for power at the coil and at the injectors with the key on.

No power at the coil it's the ignition switch or related wiring.

No power at the injectors it's the DME relay.

Power at the coil and injectors points to a bad reference sensor. The connector may be corroded and/or not plugged in all the way or cracked and may have broken the wires inside.

Check if the sensor is working by pulling a plug wire, inserting a spare plug, grounding the plug to the intake and cranking the engine. If there is spark then the reference sensor is working.

Could be the second set of contacts in the DME relay. These are for the fuel pump. The fuel pump should run for a half second after you stop cranking. Have someone listen for it behind the passengerside wheel well. Check the fuse for the pump too.

On the early 944's you can use an alligator clip jumper between Aux fuse #2 and #3 to run the fuel pump directly. Count from the drivers door. Don't leave the clip on.

Come back with your findings.

[Porsche-O-Phile]

You can also jumper terminals 30 & 87b on the DME relay to run the fuel pump. If it doesn't run, that's your problem. On one of my project cars, the pump was just sticky (had been sitting for quite a while), so I tapped on it gently with a rubber mallet. It started running and has been fine since. Just another random thought. More likely it's the DME relay or something like that though.

[SoCal Driver]

Jeff, You ever owned an early 944 or worked on the relays of a 924S? The fuse-relay block is under the dash just above the drivers left knee. Easy to get too IF you take out the driver seat.

Now having the fuse block under the hood where you hardly bend over to get to it is sweet! Thus the importance of finding out what year it is.

[eresener]

Thanks Jeff but as you can see I have an 84...and I was wodering just where the 30 & 87b terminals were now hiding...but Hugh summed it nicely...TIA Hugh...I'm waiting untill it cools down this evening before I go out and see what I can find (it's about 90 out there with 75% humidity)...so I'll let you know what's up later...many thanks

Ed

[eresener]

I finally got an opportunity to go out and work on the car...and now it dosen't even crank...checked the battery and all is good...and I could even hear the fuel pump spin up...so now I know it's not the pump...but now nada again...after all this time with the car running/working somewhat well...I guess I should expect to pay the piper...

[SoCal Driver]

Might want to check the positive cable connection(s) on the battery. If the cable has been cut, stripped back and clamped to one of the after market terminals it just may have enough corrosion to cut the current going to the car. Charging path is from the alternator to the starter then through the large cable to the battery. Power to the cars electricals is through the three ten gauge wires. These corrode and cause mayhem with the electrical and the DME. Also check the ground from the battery to the chassis and from the chassis to the engine.

[AeroSS_87]

Yeah pretty much what SoCal said. The good side to this, is now you know almost for sure it's power source related. Unless you have a two-part problem like these cars seem to have... at least mine.

Considering you said the gauge kind of fluttered, I instantly was leaning to the power supply problem... like a loose connection.

When the car was cranking, did it feel like it was hard to crank? As in low voltage or something? More so, did you run it down enough to kill the battery overnight? Just a thought.

Good luck man! Btw-I know what you're saying about the temps here.. I had to take this black on black Porsche on a 120 mile trip today with no a/c... argh!!

[eresener]

Well I think I have found the culprits. Check out these pics at the following:

http://s53.photobucket.com/albums/g70/eresener/

The Original positive cable covering has cracked right behind the connector and the three 10 gauge connectors are pretty well messed up. The ground cable is the original...and it is corroded in places...time to replace all...and we'll see what happens next.

[SoCal Driver]

Thats not an original ground cable. At least not the battery connector. Get a proper ground cable that is swedged and solderd. Like the original positive cable. Also get proper copper lugs and crip and solder them to the ten gauge wires.

[AeroSS_87]

EDIT - noticed this was an early 944... ignore this post.

[eresener]

Thanks Hugh...
The ground cable is also the same style (twisted copper wire) from the firewall to the block....also can you tell what swedged means...
anybody have pics of where exactly the battery ground connector is grounded on the body...this one is attached to the cruise control mounting bracket on the front of the batterybox wall.

[SoCal Driver]

Swedged. Crimped. Crushed onto the wire. Like the end connector on the ground wire shown. The end with the bolt through it.

I use a brick shaped piece of steel and a hammer to crimp/swedge. Then a propane torch to heat the lug for flowing the solder.

[todwic]

another socal salvation. btw, I am fond of using a pos. jumper to the 9 pin connector by the brake booster. for running the fuel pump, that is.

[eresener]

Well guys, I got all the connectors redone...new pos battery connector, three new lugs on the 10 gauge wires, new ground wire/connectors for the battery...now engine cranks over...but still no start...this is a slow process... but I will track down the prob...and thanks for all help...next I am going under the dash... how do I remove drivers seat so that this old man can get under there?
TIA,

[bigbird944]

slide it all the way back and remove the two bolts on the sliders then move it all the way forward and remove the other two bolts. i believe thy're allen head bolts.

[SoCal Driver]

Did you do the no spark quick test? Voltage at the coil and at the injectors with the key on?

No voltage at the coil is the ignition switch.

Voltage at the coil but not at the injectors in the DME relay.

Voltage at both check the sensors.

If you have spark but no start then check the fuel pump fuse.

To bypass the DME relay with out removing it run a jumper from the battery to the coil and a jumper from aux fuse #2 to #3 to run the fuel pump. The coil jumper will power the DME too.

You can use a mirror to get to the DME relay. Has "DME" on the top of it. Check www.clarks-garage.com for it's location.

[Porsche-O-Phile]

Just re-read this - sorry but I didn't realize you had an early car. Yea, the fuse block is a bit of a pain to get to like Hugh said. . . One good thing about the later cars I suppose, although I much prefer the location of the DME itself in the early ones. . . Why they moved it I'll never understand.

Anyway best of luck with the diagnosis - sounds like you're in good hands and getting good guidance! Stick with it - it'll pay off!

[eresener]

Well back at it again today...I will try (with help from friend) to do the 5 minute check...in the meantime see link and tell me which is the dme relay...i can't find it on our hosts listed diagram for relays and fuses...

http://s53.photobucket.com/albums/g70/eresener/?sc=3

or is it the dme itself?

TIA