First off, I am a complete novice when it comes to electricity, so I approach auto electrical problems with caution. But I am coming to the conclusion, after reading many, many threads on here, that my car may be poorly grounded for whatever reason. A few things I've noticed:

1) I have the shudder on the 2-3 shift that many have complained about on here, even back when their cars were new. Overall, shifts are kind of lazy. I have done two drain/fills with Matic-S which made almost no difference.

2) When I put the trans in D, there is about a full second delay before it engages.

3) One of my horns is fried (doesn't work at all) and it blows the fuse every time I press the horn more than a second. I unplugged it and the other one works fine, but sounds a little wimpy.

4) Turned the rear defroster on yesterday while sitting at a stoplight and it made the engine idle drop. Tried it several times to be sure and it did it every time. I've never had a car that does that. I don't think it should be drawing that much current.

So, I welcome any and all opinions. Am I way off base here? I did order a set of Black Betty's grounding wires this week and should get them installed this weekend. Am I overly optimistic to think that they will cure all the ills?

 

I dont have any issues that you listed

Did you buy the car used?

You may try to run a 4ga ground from your battery to the chassis and see if that helps.

Also, check your current ground from the battery to make sure it inst loose or covered in dirt.

 

+1

None of those issues here. Could be a weak battery or a poor battery neg connection (bat neg to chassis)

Ground wires can't hurt, but make sure you have the battery load tested and look for high resistance (rusted, worn, frayed) connections

 

The horn simply went bad. Replace the horn and that problem should go away. Not sure about the rest though. I put a ground wire kit on my car that steadied out a bunch of small things, though none were real problems, just annoyances.

 

1) Trying resetting the ECU and driving a little more aggressively. The ECU/TCM adapt to driving habits and throttle usage. Changing fluid will make absolutely no difference.

2) It takes a moment for the transmission to engage when D or R are selected. There are pumps and fluid movement so the response won't be instanteous. Additionally, there are programming safeguards in place so that the tranny does simply pop into gear, putting unnecessary stress on the tranny.

3) Replace the horn and check the condition of the wiring.

4) The rear defroster can draw a lot current. It wouldn't surprise me if the rpms were to drop a couple hundred rpms when it's engaged. I've paid attention, but then I rarely use the rear defroster. If you're seeing a major drop in rpm, your battery can be on the way out or the alternator.

 

If your car has been hit and the shop took it apart, there's a good chance they didn't proper connect all the wiring grounds back. Check each ground is just about all you can do

 

I have done a couple of ECU resets using both the "disconnect bat for 12 hours" method and the "disconnect and pump the brakes" method. It didn't seem to make a difference in the shifts, but I didn't really change my driving style (I drive over 80% highway).

I hear ya DaveB that the shift into D won't be instantaneous, but this is to a degree where it is very noticably longer than other cars I've owned, including a couple of Maximas.

I guess the horn is just an isolated incident. I'll replace with one from a junk car I have access to. Pretty sure it's the horn, not the wiring. Bad one is bad and the good one is good no matter which harness I plug them into (tried switching them).

The rear defroster only drops RPMs about 50, so just an annoyance, but still unexpected.

Maybe none of these are real problems and just annoyances as GAU-8 said, but I'll give all of the ground wires under the hood a once over and then install the BB ground wires and see what happens. Oh yeah, Jeff, my car has been hit, but it was all cosmetic and shouldn't have required them to touch wiring under the hood, but I'll certainly double check.

Thanks for all of the good ideas, guys.

 

my car actually does ALL of those things. also if i turn the rear defroster on. my stereo goes completely static.

 

The reason the rpm drops when you hit defrost is because it's engaging the ac compressor to dry out the air before it hits your windshield. If anything, the rpm should rise as a response to the extra load.

 

^^^ he said rear defroster

 

I think he means the rear defrost...not the front.

I'll look tonight on my ride home if my RPMS drop when i turn that on.

 

I'd go over all the grounds you can get it. Uncrew the bolt, clean up the wire connector and the metal it's grounded to. Then screw it back down. You might find 1 or 2 are perhaps disconnected.

 

there is continuous power to rear defrost... its not likely that turning it on is going to drop rpm (in normal circumstances)...

 

OP how old is your battery?

 

The born-on date is some time in 2007, but I'll have to check again to verify the month. So at worst, it's 3 years old. The terminals look perfect, no corrosion, dirt or anything.