1987 C4 Security Problem
Thread Starter
Intermediate
Joined: Nov 2007
Posts: 28
Likes: 0
From: Las Vegas Nevada
1987 C4 Security Problem
Ok, My key has failed to turn off the security since i bought the car a few months ago. Car ran ok though. Found it was gettin way too much fuel due to the bad fuel regulator-maybe thats why it ran? Anyway, the car stopped running so i replaced the fuel pump-but it doesnt seem to be working properly. Any one know how to permanently disable or bypass the security system? Also-----wheres te damn fuse panel???Think I might have a bad fuel pump relay, because the fuel pump is only priming for a second or 2 when ignition first comes on"sometimes". HELP?
Race Director
Joined: Jun 2005
Posts: 17,640
Likes: 1
From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Fuses are in the passenger side door jam
Is the security light blinking or on (can not remember which) when trying to start?
The fuel pump will only energize for ~two seconds when the key is turned to acc.
To disable the security you need to know your VATS code and install the bypass or buy a resistor of that value and install at the base of the steering column.
It might also help if you purchase the service manual.
Is the security light blinking or on (can not remember which) when trying to start?
The fuel pump will only energize for ~two seconds when the key is turned to acc.
To disable the security you need to know your VATS code and install the bypass or buy a resistor of that value and install at the base of the steering column.
It might also help if you purchase the service manual.
Thread Starter
Intermediate
Joined: Nov 2007
Posts: 28
Likes: 0
From: Las Vegas Nevada
I know I know---service manual. Im just not loaded enough yet-lol. I have a 73 Charger that I am trying to fix as my daily driver, so every lil dollar is important right now. I found the problem with the pump-the damn manual had me hook it up WRONG. It was pumping backwards-lol! The car runs great now-ther than some heavy white "lean" smelling smoke on warm up-not teary eyed-it smells like its burning good. Damn electronic cars are a pain in the ***. I bought this car for my son to sport in High School. I learned on old school carbs man, these sensors and computers are killin me! I had to disconnect the horns because the security system was actually going off, but the car will drive....???
Race Director
Joined: Jun 2005
Posts: 17,640
Likes: 1
From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Glad you got it fixed.
Yeah I know all about the electronics and sensors, just multiply by a zillion for my C5. Check your doors out that was causing the alarm to trigger on my 86. I had problems with the key cylinder as well as the switch that arms the alarm when locked.
Yeah I know all about the electronics and sensors, just multiply by a zillion for my C5. Check your doors out that was causing the alarm to trigger on my 86. I had problems with the key cylinder as well as the switch that arms the alarm when locked.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Stock timing is 6* BTDC, you need to disconnect the EST, it's a single wire close to the wiper motor..it just unplugs, set the timing and reconnect. Don't mess with the idle, should be around 650-700 when at operating temp. if the idel is irratic it will probably come down to the IAC being carboned up.
As far as the alarm goes....make sure your key lock on the door is straight up and down when the key is removed, alot of guys have found this to be the problem. I ended up going with an after market alarm with remote functions....keyless door entry, hatch release etc.
Got it at BestBuy, they did the install.....not bad $$$ and they did a very professional job.
As far as the alarm goes....make sure your key lock on the door is straight up and down when the key is removed, alot of guys have found this to be the problem. I ended up going with an after market alarm with remote functions....keyless door entry, hatch release etc.
Got it at BestBuy, they did the install.....not bad $$$ and they did a very professional job.
Thread Starter
Intermediate
Joined: Nov 2007
Posts: 28
Likes: 0
From: Las Vegas Nevada
Thanks a bunch. The Alarm works again, but the cockpit lights shut off on me the other night. I tapped the dash and they came back on-maybe a loose plug or wire? Also, is that idle speed in park or in gear?
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Advanced
Joined: Jul 2023
Posts: 90
Likes: 13
Reviving this thread - Security problem on my 1987
Fuses are in the passenger side door jam
Is the security light blinking or on (can not remember which) when trying to start?
The fuel pump will only energize for ~two seconds when the key is turned to acc.
To disable the security you need to know your VATS code and install the bypass or buy a resistor of that value and install at the base of the steering column.
It might also help if you purchase the service manual.
Is the security light blinking or on (can not remember which) when trying to start?
The fuel pump will only energize for ~two seconds when the key is turned to acc.
To disable the security you need to know your VATS code and install the bypass or buy a resistor of that value and install at the base of the steering column.
It might also help if you purchase the service manual.
