Starting problem need some ideas
Race Car
Joined: May 2003
Posts: 4,240
Likes: 103
From: SoCal
"During cranking
Starter voltage - Starts off at 12.82 and then drops to 6.8 while it is cranking
Solenoid voltage - 3.5-4.5 (Voltage dropped)"
That's the problem! You have something wrong with the wiring.
Starter voltage - Starts off at 12.82 and then drops to 6.8 while it is cranking
Solenoid voltage - 3.5-4.5 (Voltage dropped)"
That's the problem! You have something wrong with the wiring.
Guru
Lifetime Rennlist
Member
Rennlist Small
Business Sponsor
Lifetime Rennlist
Member
Rennlist Small
Business Sponsor
Joined: Aug 2001
Posts: 15,751
Likes: 104
From: yorba linda, ca
Are you guys thinking its a voltage drop across the solenoid trigger wire? If so, rig up a momentary switch from the battery to the starter solenoid, directly. This may isolate some trouble.
Robin, in your case, the trick is to get the car to fail so you can troubleshoot. Really frustrating these problems are.
Robin, in your case, the trick is to get the car to fail so you can troubleshoot. Really frustrating these problems are.
Thread Starter
Rennlist
Lifetime Member
Lifetime Member
Joined: May 2001
Posts: 3,651
Likes: 8
From: Chino hills, CA
Chris,
Thanks for the idea. That's something I thought about too... But I am trying to play out the scenario in my head... So when if... I get the car not to start, hook up a wire to the startet solenoid connection on the starter and run another wire from the battery and then while at the same time I turn the ignition key make the jump connection? If the car starts disconnect the temporary connection right away?
Thanks for the idea. That's something I thought about too... But I am trying to play out the scenario in my head... So when if... I get the car not to start, hook up a wire to the startet solenoid connection on the starter and run another wire from the battery and then while at the same time I turn the ignition key make the jump connection? If the car starts disconnect the temporary connection right away?
Guru
Lifetime Rennlist
Member
Rennlist Small
Business Sponsor
Lifetime Rennlist
Member
Rennlist Small
Business Sponsor
Joined: Aug 2001
Posts: 15,751
Likes: 104
From: yorba linda, ca
Robin, actually simpler than that. Once you can get the car to -fail-, run a temporary wire from the solenoid trigger wire, to the battery. Just touch it to the battery positive side to see if the engine turns over. No need for the key to be in the ignition.
Hope this helps...
In the end, I seem to think your starter is suspect. I wish I had one laying around for you to try, since you are only a few minutes from me...
Hope this helps...
In the end, I seem to think your starter is suspect. I wish I had one laying around for you to try, since you are only a few minutes from me...
Race Car
Joined: Feb 2005
Posts: 4,681
Likes: 11
From: Johns Creek, GA
Robin,
Have you changed / cleaned your battery connectors? I was having a very similar problem a couple of weeks ago. I thought it was the battery so I went ahead and bought a new one.
If the car was cold, it would crank fine, once it was warmed up, it would take 2 tries to get it to start and it felt like my battery was weak, almost like there wasn't enough juice to turn the engine over.
I found out that the lead ends that connect to the battery posts had develop a waxy substance inside. I cleaned both connectors with mild acid and cleaned them with a wire brush until they were nice and shiny. So far so good....
Why would make a difference if the car was warm or cold, who knows, maybe the resistance is greater as the temperature raises???
Have you changed / cleaned your battery connectors? I was having a very similar problem a couple of weeks ago. I thought it was the battery so I went ahead and bought a new one.
If the car was cold, it would crank fine, once it was warmed up, it would take 2 tries to get it to start and it felt like my battery was weak, almost like there wasn't enough juice to turn the engine over.
I found out that the lead ends that connect to the battery posts had develop a waxy substance inside. I cleaned both connectors with mild acid and cleaned them with a wire brush until they were nice and shiny. So far so good....
Why would make a difference if the car was warm or cold, who knows, maybe the resistance is greater as the temperature raises???
Rennlist Stories
The Best Porsche Posts for Porsche Enthusiasts
9 Features and Characteristics That Only Porsche People Understand
Verdad Gallardo
I've Written 500 Rennlist Articles: Here's How Porsche Has Changed Along the Way
Joe Kucinski
10 Most Unnecessary Porsches Ever Built (And Why We Love Them)
Verdad Gallardo
Porsche 911 GT3 S/C vs 718 Spyder RS: 10 Categories, One Winner
Joe Kucinski
This Builder Is Turning Heads With Its Slantnose 911 Creation
Verdad Gallardo
Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture
Verdad Gallardo
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look
Verdad Gallardo
10 Porsche Colors That Have More Personality Than Most People
Verdad Gallardo
Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod
Verdad Gallardo
Rennlist Member
Joined: Apr 2002
Posts: 189
Likes: 0
From: Indiana USA
Robin: I think you have a bad battery. Chances are the new one you purchased is defective. Is it a gel battery? If not take the battery back to the seller. Ask them to perform a load test. I'll bet it's junk. Get a new gel battery and your troubles are over.
pph
pph
Racer
Joined: Feb 2006
Posts: 488
Likes: 1
From: Long Beach, CA
Robin: no Porsche-specific expertise on this but on my wife's Saab, a similar problem that was driving us crazy was not fixed by a new battery or a new starter cable. But when the Saab tech replaced the ignition switch (I was skeptical!) it totally cured the problem. (And the old switch still looked perfect). Has anyone on this board experienced ignition switch failure on the 993?
--chris
--chris
Thread Starter
Rennlist
Lifetime Member
Lifetime Member
Joined: May 2001
Posts: 3,651
Likes: 8
From: Chino hills, CA
Ok, any advise on how to take the ignition switch out? The switch is secure on with what looks like two anti tamper bolts... Are those the same as the DME bolts, needing a drill to take it out?
Rennlist Member
Joined: Apr 2002
Posts: 189
Likes: 0
From: Indiana USA
Originally Posted by Robin 993DX
Ok, any advise on how to take the ignition switch out? The switch is secure on with what looks like two anti tamper bolts... Are those the same as the DME bolts, needing a drill to take it out?
Drifting
Joined: Aug 2005
Posts: 2,031
Likes: 5
From: San Diego, CA
The chances of getting a starter from a junk yard that was bad/tired is very high......I actually replaced a starter in my last 911 with a brand new factory one and it was bad right out of the box.
It sucked to have to do the labor all over again but when I installed the second new one it worked perfect from then on.
I think you need an Optima gel battery and another starter........ZP44
It sucked to have to do the labor all over again but when I installed the second new one it worked perfect from then on.
I think you need an Optima gel battery and another starter........ZP44
Racer
Joined: Feb 2006
Posts: 488
Likes: 1
From: Long Beach, CA
Robin: I didn't know you have to drill out the switch. don't do that yet. Battery is the easiest thing to try and is the problem in 90 percent of these cases (although since you've switched it once.....) Can you temporarily swap in the battery from your 996, just to see if that is the problem?
--chris
--chris