Won't start! HELP! - Pontiac GTO Forum
User Tag List

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 11 (permalink) Old 04-11-2014, 08:30 AM Thread Starter
 
Join Date: Apr 2014
Location: Yorktown, VA
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Won't start! HELP!

1968 GTO w/ 400. Eng and tranny have 9K miles. Last week after getting on the highway and having a little fun with her I stopped at a gas station. Came back out and nothing! A buddy jumped the car with no issues. The battery is brand new and reads ok. The car did fine for a week at normal driving conditions. I replaced the alternator just in case. Then yesterday after taking her on the highway and getting on her a little the same thing happened, but this time she won't even jump start! No sound at all with the key turn, WTH! Starter? Wiring harness? Short? I am a newbie, so go easy on me.
USCGBM is offline  
Sponsored Links
Advertisement
 
post #2 of 11 (permalink) Old 04-11-2014, 09:53 AM
 
jmt455's Avatar
 
Join Date: Mar 2012
Location: SE Michigan
Posts: 725
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Buy or borrow a remote starter switch, or jump the solenoid terminals with a screwdriver to see if it turns over. Make sure you are bridging the +12v "BAT" terminal to the "S" terminal on the solenoid. IIRC, the S terminal has the purple wire.

If it cranks with either of those methods, then you'll know the problem is in the ignition switch or starting circuit/harness. Could be a bad ignition switch, a flaky neutral safety switch or an open circuit in the starter solenoid circuit.

1968 Pontiac GTO
1983 Pontiac Bonneville (G) wagon
2008 Pontiac G8 base
jmt455 is offline  
post #3 of 11 (permalink) Old 04-11-2014, 05:28 PM
Ace
 
Ace's Avatar
 
Join Date: Mar 2014
Posts: 26
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Garage
Does it start okay after it sets and everything cools down? If so, it could be a "heat soak" issue with your starter. Just an idea.
Ace is offline  
 
post #4 of 11 (permalink) Old 04-12-2014, 06:57 AM
 
pjw1967's Avatar
 
Join Date: Mar 2014
Location: The Woodlands, TX
Posts: 440
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
My '67 did that. Eventually went to a high torque mini starter and Nbr 2 gauge cables. No hot start issues since.
pjw1967 is offline  
post #5 of 11 (permalink) Old 04-29-2014, 04:36 PM
 
jrdeleon1's Avatar
 
Join Date: Oct 2011
Location: Patterson, CA
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I had the same problem on my Custom S. I have headers coming down near the starter so it overheats it. Put a shield on the solenoid or the whole starter and it should keep it cool.
jrdeleon1 is offline  
post #6 of 11 (permalink) Old 04-29-2014, 05:08 PM
64-67 Expert
 
geeteeohguy's Avatar
 
Join Date: Feb 2008
Location: Fresno, California
Posts: 8,529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 112 Post(s)
9 times out of 10 it's high resistance in the purple 'S' wire from the ignition switch to the solenoid. If you can start it by jumping the S and Bat terminals on the solenoid, that's the problem for sure. I've run into this on MANY old Pontiacs. On my own '67, the "S" wire was bad right behind the ign. switch.
geeteeohguy is online now  
post #7 of 11 (permalink) Old 04-29-2014, 07:49 PM
 
PontiacJim's Avatar
 
Join Date: Dec 2012
Location: Gastonia, NC - Born & raised in Connecticut - 31 years
Posts: 3,632
Mentioned: 1 Post(s)
Tagged: 1 Thread(s)
Quoted: 384 Post(s)
Garage
Many good suggestion and most of which I have and would also try myself.

My experience with this seemed the solenoid on the starter would go bad. When younger, I didn't know what I know today about the heat shield that is available to protect the solenoid from the exhaust manifold heat. I ran my cars hard and the solenoid most likely got pretty hot at times and burned 'em up. I used to keep a spare solenoid in my trunk at all times, no matter what Pontiac I happen to have registered at the time. I got pretty good at dropping a starter in a parking lot, installing a new solenoid, bolting it back up, and going about my business in about 20-30 minutes.

If you turn your ignition key on, does the red generator light on the dash come on? It should. If not, then perhaps you are not getting power to the switch. If you get the "gen" light and no start, it could be the ignition switch, but don't decide quite yet before doing other checks.

Now it has been a while since I have done this, so somebody correct me if I am wrong, please. You could use a test light to make sure you have power at the starter solenoid at the 12V BAT terminal. Then put your test light on the "S" (purple wire) terminal. It should light up when you turn the ignition key all the way just as you would to start the engine. If test light lights up, but engine does not turn, my guess is it is the solenoid or the starter. If it does not light up, then it could be the contacts inside the ignition switch have gone bad (this happened on my Lemans -they do wear out), or the purple wire to the solenoid has issues.

Things that can pose a problem that can be checked, corroded battery cable, bad ground cable, solenoid, the starter itself, neutral safety switch on an automatic (try it in neutral & park and jiggle it to test -short of it gone flat bad), wires going to the solenoid as described, ignition switch gone bad. I am pretty familiar with jumping the solenoid terminals with a long screwdriver (could never afford a remote starter switch) as I had to do that a number of times as well. Was easy as I had no heat shield and stock manifolds.

Just do your checks step by step to eliminate/narrow down the problem. Get stumped, just post an update and let us know what you did or need to do.
PontiacJim is offline  
post #8 of 11 (permalink) Old 04-30-2014, 01:34 PM
64-67 Expert
 
geeteeohguy's Avatar
 
Join Date: Feb 2008
Location: Fresno, California
Posts: 8,529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 112 Post(s)
Jim, the problem with the test light is that it won't check for current...just voltage. Even if the resistance is very high in the S wire, the light will still illuminate, but nothing will happen at the solenoid because the current isn't available. I usually find that every time I replace the complete S wire from the switch to the solenoid, no heat shields, trick starters, or remote solenoids are needed for easy starting. It's simply a matter of 45-50 year old wiring building a lot of internal resistance and preventing current flow. That's why jumping the S and Bat terminals at the solenoid itself is a great way to determine if it's an S wire problem, battery wire or battery problem, or solenoid issue. I'm stating this because I've run into this a lot on these cars, and it always seems to be that pesky S wire.
geeteeohguy is online now  
post #9 of 11 (permalink) Old 04-30-2014, 04:52 PM
 
PontiacJim's Avatar
 
Join Date: Dec 2012
Location: Gastonia, NC - Born & raised in Connecticut - 31 years
Posts: 3,632
Mentioned: 1 Post(s)
Tagged: 1 Thread(s)
Quoted: 384 Post(s)
Garage
Quote:
Originally Posted by geeteeohguy View Post
Jim, the problem with the test light is that it won't check for current...just voltage. Even if the resistance is very high in the S wire, the light will still illuminate, but nothing will happen at the solenoid because the current isn't available. I usually find that every time I replace the complete S wire from the switch to the solenoid, no heat shields, trick starters, or remote solenoids are needed for easy starting. It's simply a matter of 45-50 year old wiring building a lot of internal resistance and preventing current flow. That's why jumping the S and Bat terminals at the solenoid itself is a great way to determine if it's an S wire problem, battery wire or battery problem, or solenoid issue. I'm stating this because I've run into this a lot on these cars, and it always seems to be that pesky S wire.

OK, I can agree with that. If corrosion or something of that nature affected the wire then there would be voltage flow, but not the needed current flow -there would be resistance. I have used an Ohm meter on occasion and again, been a while in using one, recall this would show the current flow (voltage) or drop in current flow? I hate electrical/wiring problems. HaHaHa.
PontiacJim is offline  
post #10 of 11 (permalink) Old 04-30-2014, 11:04 PM
 
chuckha62's Avatar
 
Join Date: Apr 2010
Location: NorCal
Posts: 711
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 18 Post(s)
Great suggestions on the wiring, but that's not the whole picture. Remember that inside the end cap of the solonoid is the copper post which contacts a copper disk. The contact point of these two items becomes a source of high resistance due to the repeated arcing over time. This can be remedied as a free fix by taking it apart and removing and rotating the post 180 degrees and flipping the copper disk over. This gives two new, clean contact surfaces.

I've done this numerous times and saved myself and other alot of aggravation and $$ over the years.

When the only tool in your toolbox is a hammer, you tend to see every problem as a nail.
chuckha62 is offline  
Sponsored Links
Advertisement
 
Reply

  Pontiac GTO Forum > The 1964-1974 Pontiac Tempest, Lemans & GTO > 1964-1974 Tempest, Lemans & GTO General Discussion

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Pontiac GTO Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Car won't start 11bravogoat Engine Discussions 4 01-09-2014 03:46 AM
my 350 2-barrel won't start now. poncho power 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 10 04-01-2013 09:45 AM
GTO won't start...not firing... offroadfury6 Engine Discussions 4 02-25-2013 05:16 AM
car won't start HELP! camarocasanova 1964-1974 Tempest, Lemans & GTO General Discussion 14 12-03-2008 09:27 AM
New Goat won't start BlackSheep 2004-2006 GTO General Discussion 14 12-14-2006 10:13 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome