Austin87

Long story but have to go step by step. I have an 87 924S - purchased in September from a forum member Robert Hughes of Orlando who is now moved to Iowa. The car was his wife's DD for 7 years and he did tell me he was a Porsche Technician and always meticulously maintained the car for her.

Problem I have is since I have the car, there has been a problem with the car cranking but not starting about once a week. When running the car always ran very smoothly. I remembered Robert the PO telling me something about if the car gives me a problem no starting to clean the grounds or just wiggle the Ref sensor wires around and the car will start up. He said that eventually it will probably be a good idea to install new ref sensor wires.

This went on for the first 3 months or so and I figure soon I have to replace the 2 reference sensors. Then in about December of month 4, this would happen more frequently to about 3 times per week. And maybe have to give more than 1 wiggle of the wires to get it to start. But still after 2 or 3 tries of wiggling the ref sensor wire the car would start up.

When driving the 924S I put on about 5,000 miles and the car when it is running always ran very well. Idling - accelerating - shutting off and coming back on . Unless this issue would come up but it always ran smoothly.

Then about 4 weeks ago one night after starting up and driving like 50 yards the car actually stalled out on me for the first time, and didn't start back up. I eventually got it to start up after like 10 minutes of waiting , but it stalled out quickly. I put in the new DME relay I had just for good measure but it didn't fix the problem. I eventually drove it home like 2 hours later about 3 blocks on it's own power.

Since then I had the 924S towed to Mike Goeke at German Performance Inc. in Ft Lauderdale who I was referred to by a member here or on Pelican. Mike Goeke tells me he is a 45 year Porsche factory trained technician and he has a garage full of Porsche's which seem to back up he knows his way around them very well. On the first try with the car Mike tells me he can diagnose the problem only if the car is not starting & he did have that chance after I had AAA tow it to him, about 4 weeks ago. I told him I think maybe I need to clean or change the reference sensors but he said this is not possible to be the problem. I am not an auto mechanic but he is so I let that go even though it is against what I was told could likely be needed by Robert Hughes.

What Mike did was swap out my air flow meter for one he had in his garage and told me the problem is fixed. It "started up 20 times for him, plus it now ran smoother and sounded alot better". Then the night I was going to pick it up he had a guy move it out and it didn't start. They now cleaned the ref sensor cable grounds and switched them around and it was now starting w/o stalling out.

* He also tightened my loose Water pump belt and installed a low radiator sensor switch which he found I needed because the car was running hot and the radiator was cool so my pump wasn't turning . I was very grateful he found this out. So I picked it up . ( $500.) Drove it home 30 miles highway and street with no problem. Then I went out to start it 10 mins later and it did not start up again. Tried the same things with the wires and no luck.

Last Friday afternoon AAA Towed it back to German Performance this time with 2 new reference sensor wires for him to install. Today I picked it up . It started for him fine he said and for me 2 times so I drove it home ( again). Back to move the car 30 minutes later and same problem again. Car won't start. Wait a few minutes and it starts and stalls out. Wont start - called Mike Goeke and the call did not go well. He said he needs the car when it is not stating in order to diagnose the problem correctly not after a new air flow meter and new sensors. I tried telling him that is where we started out but he was not happy to hear that. A minute later on my 3rd try to explain this point , he hung up on me. Here is where I am now.

Anyone have any suggestions on what this could be or where to go with it. To me it seems like it would be a lack of getting fuel issue. I have had it with the car and being an automatic even though I put time and $$ into this and it is alot of fun to drive I want it fixed and gone. First fixed .

Thanks, Austin ( West Boca Raton , Fl )

Arominus

First off, the guy you went to sounds like someone I would not do business with. He is being rather ****ty with you and he is the reason you want to get rid of the car.

Next, Does the tach bounce when you try to start it? if not then the Ref sensors are it. If it does you need to check for fuel pressure and for spark from the coil wire when its in a no start mode. Go to clarks and go down the No start check list. Look to make sure the shop actually installed your reference wiring you gave them. If you can't do these things then FIND ANOTHER SHOP.

edit. "* He also tightened my loose Water pump belt and installed a low radiator sensor switch which he found I needed because the car was running hot and the radiator was cool so my pump wasn't turning . I was very grateful he found this out. So I picked it up . ( $500.) Drove it home 30 miles highway and street with no problem. Then I went out to start it 10 mins later and it did not start up again. Tried the same things with the wires and no luck."

This is an extremely suspect statement. Your water pump belt is the timing belt, it always spins no matter what. The Temp switch on the rad controls the fans but the pump always runs. The 924S is an auto tension motor so it shouldn't really require any work to do its thing, after the initial belt install it needs to be retensioned after 1500 miles and then its good to go for the life of the belt. Retensioning is a 15 minute job (pop the front timing cover and loosen the tensioner, spin the motor twice, retighten tensioner and replace the cover)

konakat

Sounds like throttle position sensor or reference sensor issues. Clean the TPS connector contacts and test it using Clark's guide. If you still have issues, you can try cleaning the reference sensor connectors. After that you have to start suspecting the reference sensor wires going back to the DME. If you have access to an oscilloscope it would be much easier to know for sure if the reference sensors are the issue, but that is not something most people have sitting around. Oh, and the first guy you went to is a crook.

Austin87

When not starting the tach moves very slightly only. It is a hair above not moving. So yes it bounces but almost as little as possible and still moving up & down...

.....................

Austin87

Hi.. I do not have an ocilloscope ( nor can I spell it ) but I willl try checking the TPS contacts tomorrow morning. Sounds like a possible suspect & thank you ...will advise back tomorrow....

Austin

Austin87

I do not see any "no start check list ". Would anyone be able to port that link ?

[/QUOTE] Look to make sure the shop actually installed your reference wiring you gave them. If you can't do these things [/QUOTE]

Yes they are installed and the old ones are in the boxes on my front seat, so the car does have new ref cable installed. ...

Thank you. AA

...

Arominus

Sorry, called it the wrong thing. Here you go. http://www.clarks-garage.com/shop-manual/ts-01.htm

Austin87

Throttle position sensor or throttle position switch please..? I removed the TP sensor plug; sanded the contacts; blew them out with air; and reconnected the sensor plug.....

...

konakat

Switch. My bad

Austin87

OK... so on my 87 924s this is under the throttle body. Clarks garage shows "Throttle Position Switch Information, Troubleshooting, Replacement, and Adjustment" .... and directs to check at the DME control unit. But the TPS is still the same part that I just cleaned contacts under my Throttle body.

Correct..?

..

odurandina

the 80s ignition circuits have lasted much longer than they should have....

but no less than what you'd expect with your average 20 year old laptop,

oops, you're cars with their ancient wiring are pushing past 30....

exposed to heat cycling, salt, frost, dirt, corrosives, grease, etc.....

my dear friends; your 924s/944s are fried.

don't stray too far from the house......


here's a reality check....


why not just take your car to the dealer and say,

"here's my 944. it runs like ****. please fix it, and call me when it's ready."

as in, Jesus, they're the ******** who built it.

konakat

Crawl back in your hole, troll. You add nothing to the conversation.

Austin87

Anyway I tried to upload a picture of the throttle body & switch under throttle that I removed and cleaned the contacts.

Also have a picture of another possible suspect which is the wire that my Speed Reference Sensor ( The one that connect towards the front of the engine vs closer to the firewall ) . The insulation of this wire (not the new Sensor wire) is partially open, showing exposed silver wire. Mike at German Performance said that this silver wire is just an insulation wire and that the connection is OK. I did take a good size magnifying glass to the open area of the wire and could not find any breaks in any wiring . I covered it with some Gorilla Tape for good measure.

odurandina

try not to get all in a pissy and intimidate the bloggers....

it should be obvious that, the part of my post you quoted wasn't the key point....

despite that it's completely true.

I can show you hundreds of failed ignition threads that clearly demonstrates this fact.

some of the problems appear to be related to the alarms..... and the ******** who represent the people who built the cars either can't do it for less than about the cost of a decent Boxster... or won't take on these jobs in the first place.

I got a problem with that... and it's not a low-production car either.

I can take an '81 Subaru GL to the Subaru dealer and have whatever I need done.

and it'll get done.

is the point of this forum, to do the absolute wrenching, all the whole wrenching, and nothing but the whole all, wrenching? sure.....

but Porsche won't fix it,

and I surmise the reason is, they know nearly the entire electrical systems are shot.

and while it's not my goal to demonize an automobile company,

I believe I have the right to make light of this while at the same time giving Porsche endless **** for it.

Porsche's version of reality is too often not called to light.....

and not being able to easily swap out a dog wiring harness in just an hour or two for a reasonable price (even relative to Porsche), is bull**** in my opinion.


so, let's review.

1. the ignition circuit's/wiring harnesses are fried. no, really, they are.

2. can't drive the cars very far with peace of mind in that regime.

3. the ignition circuit/ecm isn't easy to replace, and in no small part, do to the half dead, shorted alarms on the cars not being easy to bypass.... but after a problem, people should consider doing just that.

after 30 years, it's time.

4. if you can't fix it, Porsche maybe can't fix it either...... or, if they can,
it might not be for less than the cost of a good used Boxster.

5. in some instances, Porsche support sucks so bad; it's reached the point where
you might consider moving on altogether from Porsche in the engine bay.


.

Austin87

OK well starting up the 924S after cleaning things a bit , my idle is hovering for a few minutes from 800 to 900 rpm - and after a couple of minutes maybe 790 rpm up to 870 rpm.

.....

second try 30 minutes later & the car is back to not starting up. just cranking.....