Need two separate diagnoses please (electrical & oil issues)
Thread Starter
Safety Car
Joined: Jan 2003
Posts: 4,018
Likes: 2
From: Obscurity's Armpit
Need two separate diagnoses please (electrical & oil issues)
Basic background: I have an 80 which I use as a daily driver. It has a ZZ3 engine I installed 9 years ago. Engine was broken in w/ conventional oil, and has had Mobil 1 ever since.
Problem 1) Car wouldn't start after work a month ago; battery wouldn't even take a jump. Had the car towed to a local Vette repair shop I've patronized for years. They tested the entire electical system, including the alternator, and determined that the old battery was just shot, so we replaced it with the biggest unit AC Delco makes. Now the needle on the gauge seems to spend a lot of time hovering on or behind the twelve, even while driving, and sometimes just using the power windows or rear defroster will drop it back to around nine while those switches are activated. My guess is the alternator; if so, is there one particular high-output unit you can recommend?
Problem 2) Car normally starts on the first try, and the oil pressure usually shows to be around 50. Now, about twice a week, the oil pressure will start off at 20 and stay there for around two minutes, whether driving or idling, before suddenly jumping over to 50. Is the pump starting to fail?
Thanks, as always.
Problem 1) Car wouldn't start after work a month ago; battery wouldn't even take a jump. Had the car towed to a local Vette repair shop I've patronized for years. They tested the entire electical system, including the alternator, and determined that the old battery was just shot, so we replaced it with the biggest unit AC Delco makes. Now the needle on the gauge seems to spend a lot of time hovering on or behind the twelve, even while driving, and sometimes just using the power windows or rear defroster will drop it back to around nine while those switches are activated. My guess is the alternator; if so, is there one particular high-output unit you can recommend?
Problem 2) Car normally starts on the first try, and the oil pressure usually shows to be around 50. Now, about twice a week, the oil pressure will start off at 20 and stay there for around two minutes, whether driving or idling, before suddenly jumping over to 50. Is the pump starting to fail?
Thanks, as always.
Safety Car
Joined: Jan 2001
Posts: 4,660
Likes: 3
From: South Central Louisiana
St. Jude Contributor
Re: Need two separate diagnoses please (PartTimeGenius)
If you ever doubt a gauge, especially a factory gauge, get a second opinion from another gauge. If you are not constantly fighting a dead battery with those volt readings than I suspect if you put a volt meter on your battery you will get a totally different reading. Having a problem with both makes me think you probably have a loose connection and/or bad ground in the instrument panel area.
Instructor
Joined: Jan 2004
Posts: 246
Likes: 0
From: Marshalltown Iowa
Re: Need two separate diagnoses please (PartTimeGenius)
Oil pumps are, for the most part, the last to fail as they are the best lubricated part in the motor. While it may be a pain, check your dash guage against a mechanical before going any further. I would guess you probably have either a sensor going out or a sticking guage issue.
Any parts store will have a cheap meter you can hook up under the hood for testing.
Any parts store will have a cheap meter you can hook up under the hood for testing.
