crazy intermitent problem
Thread Starter
Junior Member
Joined: Nov 2008
Posts: 14
Likes: 0
From: Georgia
Car: 89 GTA
Engine: 5.7 TPI
Transmission: 700R4
Axle/Gears: stock
crazy intermitent problem
While driving sometimes the alternator quits charging, the engine stumbles and the check engine light comes on. After a few seconds it starts charging again and runs fine. There is no trouble codes. Has new alternator - replaced cause I thought that was the problem. This happens daily. Any ideas?? 
89 GTA 350 TPI / 700R4
89 GTA 350 TPI / 700R4
Supreme Member
Joined: Jan 2003
Posts: 2,133
Likes: 4
From: Houston, Texas
Car: 88' IROCZ
Engine: 388 TPI Motown 350 Race block
Transmission: 700R4
Axle/Gears: 2.77
Re: crazy intermitent problem
The alternator maybe overheating.
Check for any over drive pulley(s) installed to increase alternator electrical power at idle. If it does upgrade to a higher amperage alternator, or reinstall stock pulley(s.)
Check for loose connections, and replace old battery cables, while you may not want to replace the red fusible linked wire from the starter to the alternator at least check it for swelling (internal corrosion.) Add a black battery cable with lug connectors on both ends from frame to engine block ground and another directly from the alternator case to frame ground.
Make sure the "S" wire; alternator battery voltage sensor wire is good.
Check for any over drive pulley(s) installed to increase alternator electrical power at idle. If it does upgrade to a higher amperage alternator, or reinstall stock pulley(s.)
Check for loose connections, and replace old battery cables, while you may not want to replace the red fusible linked wire from the starter to the alternator at least check it for swelling (internal corrosion.) Add a black battery cable with lug connectors on both ends from frame to engine block ground and another directly from the alternator case to frame ground.
Make sure the "S" wire; alternator battery voltage sensor wire is good.
Supreme Member
Joined: Jan 2006
Posts: 3,341
Likes: 12
From: Mooresville NC
Car: LOWERED ♦ CRIMSON METALFLAKE
Engine: ► 400 KUBES ◄
Transmission: 765R4
Axle/Gears: EATON POSI 4.56
ALTERNATIVE SOLUTION
If your battery is good, an alternator failure while running will be immediately unnoticeable.
You would have to run for quite a distance before the bat would be low enuff to cause the symptoms you describe.
If your alt is overheating you will know it by just being near it.
Your symptoms are consistent with an intermittent short.
Especially because you indicated you had the problem before and after you replaced the alt.
.
Happy Racing!
.
If People Drove Any Slower They’d Be Going Backwards
.
Thread
Thread Starter
Forum
Replies
Last Post