It isn't a major problem yet, but I'm sure in a few thousand miles it'll get worse. My car shakes with a rough idle. It probably only ranges by about 50rpm, but it's very irritating. My air intake filter is clean, i just changed my spark plug and spark plug wires, and i've had my fuel injectors pressure sprayed recently. Could it be my idler pulley? When I look at it, it seems to shake slightly more than the rest of the pulleys. Maybe my fuel filter? Maybe clogged fuel rails? If anyone has any ideas of stuff that I should check, I'd appreciate it much.

So, my voltage doesn't go higher than 12.7 anymore. It used to sit at 14.0-14.2, now much lower. I changed my battery about 6 months ago, so I can't imagine that it would be that. Is there a way to check my alternator without pulling it out? I don't know if I have a major draw while the car is on that is causing the volts to drop, but there is no draw when I have the car off, as it can sit for many days and still start fine. Just now when I pulled in from getting my car aligned after I swapped out my inner and outer tie rods, my volts wouldn't go above 11.5 while idling in my garage.

As always, I love all of you guys for helping out a fellow corvette zealot! As random as any ideas sound, I'd still love to hear them. Much obliged!

 

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You need to address that voltage problem before it leaves you stranded. Start with checking both battery cables at both ends and make sure they are tight (very tight) and clean. New batteries can and do die so have autozone or somewhere load test it and they can check the alternator output at the same time. You can do this yourself if you have a meter. There are other things you can check but this is an easy way to start. Your rough idle MAY be related to the low voltage. Check your codes using the dic and see what comes up.

 

Connect a TEMP jumper wire from the battery POS terminal to the BATT terminal on the back of the alternator (under the black boot) and see if that resolves the LOW VOLTAGE issue. If it does,, let me know.

BC

 

Last night when I parked the car, it was idling at 11.5 volts. I started it up this morning and it was at 10.5 and not holding well. All of my gauges went crazy, stereo shut off, and every code came up. Everything electrical eventually shut down but the car was still driving fine. I turned around to take my other car to work, keeping my rpms up to try to get some volts to the battery. All of a sudden, BAM. Everything came back on, volts went to 13.0 or thereabouts. A few times today when I was idling, the volts just started slowly dropping to 12.0, staying there for a bit, then coming back up. I'll try your wire trick, Bill. Thanks for the help guys.

 

Sounds a lot like a loose or dirty connection. Bills jumper will shed some light on it.

 

If the problem resolves after the jumper trick,,, You have a bad connection between the alternator & battery. Most likely at the starter SOLENOID..

 

I put jumper cables from the positive terminal of the battery to the wire of the alternator. My volts went from 13.2 up to 13.6. Today, my volts have been staying around 12.8 to 13.2, so I haven't had too much of an issue. I used to be at 14.0 though, so would that mean that I need to get a new alternator anyways? My starter solenoid's wire was a little loose, I tightened it. The solenoid itself is actually somewhat loose though. Does that matter? What should be my next course of action?

 

Unless you completly resolve ALL the electrical issues at the solenoid,,, Your NOT going to be able to resolve your electrical issues.

My recommendation would be to remove the wires from the terminals clean the and reconnect propery!

Once thats done,, we can go from that point!

BC

 

Even after tightening the wires on the solenoid, I had the same problem last night where my car shut off. I'm about to go buy a new alternator real quick, as getting to the starter is very difficult with long tube headers. I'm going to get the 145amp alternator instead of the 110, as I have an aftermarket stereo in the car. I'll let you guys know how everything goes.

 

Just got my new starter, as you can't just buy the solenoid.. I swapped out the alternator and was still having the same problem. When I did Bill's trick of connecting the alternator to the positive terminal of the battery, my car worked fine though. Now to remove my header.. Hopefully I can just loosen it up to get the starter off/on.

 

It appears to me you are throwing a ton of money at this thing without testing anything. The only way the starter can make your car die is the battery connection, since that is where the whole rest of the car is also connected. The alternator should be easy to test.
Just my 2 cents.

 

The alt is a piece of cake to remove and install, so take it to a shop listed under Automotive-Electrical in the yellow pages and have them test it. If it's the original alt, you don't want to replace it as the new one won't be as good as having yours rebuilt.

 

I replaced the starter, which sucked because I had to completely remove my long tube header. The wire running from the starter to the solenoid was almost burned through. I never disconnected my battery before putting in my header a month ago, and it sent off some big sparks when I was trying to wiggle it by the starter. Replaced the starter, returned the alternator I had bought, and the car runs great. It sits at a solid 14.0-14.2 volts, and that's off of the 110 amp alternator, not bad! I used some silicone spray on all of the connections on the solenoid before putting my header back in. I definitely don't want to have to do that job again! Thanks for all of the help everyone, it looks like Bill was dead on with his guess from the get go.

 

BC

 

Bill is always right, and it must be storming there, too. Sitting on this forum instead of driving, again, damn it.

 

What I've learned in my short time on this forum is that when Bill tells someone something it's usually more than a guess.

Glad you got it resolved.

 

dragging this thread up. I've got a somewhat similar issue. My voltage will at times drop into the 11s when idling or coasting. It's always a solid 14.x when driving or under load. If I'm idling and it starts to drop, i can goose the throttle some and it'll jump back up to 14.2 or so. What do you electrical experts think? I've checked the battery after letting it sit for a few days and voltage is like 12.5 or something there abouts. So I don't think it's the battery. This never occurs while driving only idling or coasting. I've checked connections at the battery and alternator and everything seems tight. If there's a short or connection issue, would it be so rpm dependant? Could the alternator be on the way out?? any help is greatly appreciated.

edit: The orginal pulley tensioner seemed to have a lot of play especially with my large cam while idling. So I put on a Katech tensioner to rule belt slip out. Still have the problem though. Also, this is a c6 z06, thought this was in that forum. Mods please move if necessary.


Pete