Erratic Idle Now Worse
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
Erratic Idle Now Worse
I have a 1996 auto coupe. I had a little skip in my idle and the voltage was about 14.2. No problem with power. Now there is a harder skip, and the voltage goes from 13.7-14.2. Before, I would be able to start it quickly. Now, I have to crank for a while until it starts. Also, the lights would get a little dim and then go back to normal. I was thinking something with the fuel system but would that cause the voltage to change. I had replaced all of the vacuum lines but I don't know if I changed them all. I do have a vacuum line that is capped with a screw. Can't reach it and don't know where it goes. If it is that vacuum tube with the screw that is causing the problem, why did my idle go from a little skip to a hard skip? Would a vacuum leak cause the fluctuations in voltage? Alternator, a loose ground, a loose wire etc. are some of the things that might I think may cause the problem.
Safety Car
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
I have a 1996 auto coupe. I had a little skip in my idle and the voltage was about 14.2. No problem with power. Now there is a harder skip, and the voltage goes from 13.7-14.2. Before, I would be able to start it quickly. Now, I have to crank for a while until it starts. Also, the lights would get a little dim and then go back to normal. I was thinking something with the fuel system but would that cause the voltage to change. I had replaced all of the vacuum lines but I don't know if I changed them all. I do have a vacuum line that is capped with a screw. Can't reach it and don't know where it goes. If it is that vacuum tube with the screw that is causing the problem, why did my idle go from a little skip to a hard skip? Would a vacuum leak cause the fluctuations in voltage? Alternator, a loose ground, a loose wire etc. are some of the things that might I think may cause the problem.
The fact that now you have to crank it for a while before it starts, kinda leads me to think fuel pressure. I would check that out to start with.
Anymore description of the issue/symptom would help.
A vacuum leak (if big enough) will cause idle problems, but should run ok the rest of the time, maybe.
Where is this vacuum line at?
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
Someone also told me that it was a voltage regulator. The part doesn't cost alot so maybe I'll try that first. I just need to find out where in the engine it is and is it an easy remove and replace. If that don't work, I'll soon be buying fuel injectors from John and replacing the fuel filter. Thanks, Ed
Le Mans Master
Joined: May 2004
Posts: 5,866
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From: Hellinois
Finalist 2020 C4 of the Year - Modified
There are a few things that would cause what you describe but the voltage regulator is NOT one of them. If you have an error in the vacuum lines then that is where you want to start. have you checked the tps setting? A low voltage setting will cause a slight stumble. Go back to what you did first then start diagnosing instead of throwing parts ($$$) at it,, unless you have more money than you need.
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
I called Napa Auto Parts for the voltage regulator and they sell them for around $45.00 and an alternator for $175. I wonder why they sell the voltage regulator separately or is it for when you rebuild your alternator? O'Reily's also sold them separately so that's why I thought the regulator was next to the alternator and not in it.
Safety Car
Joined: Sep 2010
Posts: 3,752
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From: Indiana PA
69, alternator, c4, c6, car, causing, corvette, dim, erratically, fluctuating, idle, idles, inconsistent, lights, skips, z06
