Hey I own a '87 Trans Am 5.7L V8 350 Auto Tranny and I have had a wierd starting problem lately. my problem is this: occasionally when i go to start my car, turn key to run, hear fan and fuel pump prime, turn to crank and hear click (from starter?) and lights dim real low, fan spins real low, temp guage swings full, but no crank from starter. if i disconnect neg bat cable for 5-10 min power will come back to pump and fans but when i crank, same thing. after messing with things for awhile it will start cranking again. now i replaced alot of things related including starter, but i have narrowed it down to p/n safety switch or ignition switch. now one thing is that someone cut the purple wire going to starter "s" terminal and had a wire going from that term to yellow wire comming off ignition switch on steering column. it seems they did this to bypass the p/n switch. now down by the fuse block behind driver kick panel is a connector that has a purple and yellow wire. from the posts i read i can only think this to be for a manual trans setup for the clucth safety switch. i did a continuity test between the purple and yellow wires from that connector to the ones that go to p/n safety switch and they are connected. so if i hook that yellow wire from ignition switch to the yellow wire hooked to the connector(clutch safety switch) will this fix it? i already tried it and it worked for a few times, but then same problem. also with my Auto Xray scan tool it says Park/Neutral: not detected when it's in park and detected when it's in drive or reverse. hot swapped it with a new p/n safety switch and same thing. i just bought the ignition switch and am gonna get that in asap to see it's the problem. any ideas would be greatly appreciated.

 

Hello Strider681,
In regards to your problem I will include a schematic for your starter wiring. There is a purple wire going from the "S" post on the starter solenoid to pin "B4" of connector C100 (driver side firewall), from there it goes to pin "E" of the P/N switch. Before it gets to the P/N switch, it has a splice in it with a wire going to pin "A" of the clutch start switch (manual tranny) connector. There is a yellow wire coming off pin "S" of the ignition switch going to pin "F" of the P/N switch. Before it gets there, it also has a splice in it with a wire going to pin "B" of the clutch start switch (manual tranny). The pontiac's had wiring in place for both manual and automatic transmissions. Hope this helps you!!!!!!!!!

 

well I replaced the ignition switch and the problem went away for awhile. the starter turned over about 10 times since i replaced the switch. exceptfornow i just went out to my car after it had sat for 2 days and on the first time i tried to crank.. click! no power.. same problem... so i am going to take my starter to checker asap and get it tested.. i was wondering if a bad ( or going ) fusible link would do this?.. i'm thinking of cutting out all the fusible links and just replacing them with inline fuses. i know it's not as safe but i am really getting mad now and will try anything to have my car start everytime.

 

i was just out there messing with it for awhile and decided to disconnect p/n switch connector and jumper yellow and purple wires to rule it out. same problem so now i know it's either starter or fusible link. is it possible that a fusible link could work sometimes and not others? i disconnected the neg bat term like 20 times and it starting cranking 2 or 3 times then.. click, dead...

 

Don't replace the fusible links, they are there for a reason. The starter gets it's power straight from the positive battery cable, not the fusible link. Your problem is probably your battery cables or your battery, if it did it with the old starter and a new one. I would hook a voltmeter to the battery and see how much the voltage drops when it starts and when it doesn't (or take it to an auto parts store and have it load tested). WAG is something with the cables.

 

yeah the cables are pretty corroded.. and the battery measures 11.92 with my multimeter and 8-9 volts while cranking. it is interesting howerever that it has only done this since i replaced starter and fixed wiring as described in my original post. i plan on replacing the battery, cables, and starter tomorrow and see how that goes.. btw what is WAG??

 

Wild A**ed Guess!!!!!!!!!!!!!!!!!!!!

 

well i cleaned the battery and cables and area thoroughly today with baking soda water solution.. there was alot of corrosion built up in the neg terminal.. i have side mounts.. and i'll be damned the problem has gone away.. for now.. starter has engaged about 10 times no clicking... so hopefully this was my problem.. thanks for your guys help...