I have a 2007 g35s sedan recently when I was driving my slip and VDC off light came on. The car bucked and dropped to third gear. It also has a problem starting now.when I leave the car in automatic it will not shift out of third and shifts really hard in the rear. Kinda feels like the diff and not the transmission. In manual mode it lets me go all the way to fifth but still shifts bad. Any help on the would be extremely helpful thank you.

 

Cam pos sensor(s)

 

would it be all of them or is it a certain one

 

Check for hidden codes, there's probably one stored.

 

do you know how I could do that. I checked the codes the other day and I had a p0603 code but I don’t know how to check hidden codes

 

Just plug in an OBD2 scanner, not every code will make the instrument cluster lights turn on.

P0603 is the ECM backup battery power, make sure fusible link slot 34 fuse isn't blown out.

Also make sure all the connections on your battery are clean and tight.

 

Is it a good chance that it is the camshaft position sensors

 

I've never heard of the cam sensors causing transmission malfunction like that. Are you SURE there's no other codes? If your slip and VDC lights are on then you DEFINITELY have codes. Not all OBD2 scanners can handle all codes though, most just handle P - powertrain codes but don't handle B -body or C - chassis codes.

Most auto parts stores will scan for free and their scanners almost always handle all codes, they're trying to sell you parts to repair your vehicle afterall.

Describe in more detail the starting problem, does it feel like it's cranking weak? Does it crank strong but just not catch? Does it spit and sputter and TRY to catch?

 

For a second or to after I click the start button it’s just the starter trying to get it going but then it will start up and run fine. And the shifting problem happens mainly in first to second and second to third. It’s like a hard clunk and then almost chirps the wheels no matter what rpm it shifts at

 

I'd start by pulling and inspecting plugs, check transmission fluid level while hot, clean up the transmission ground on the timing chain cover, and inspect the rear diff bushing for an obvious signs of wear/damage.

This definitely sounds more like a transmission or shift control issue. Did you ever clean up the battery terminals?

 

I have have not do you think that my be the cause to my problem

 

Well it's controlled by a computer and these 5AT equipped cars are pretty notorious for having shift issues and general transmission issues when the ground gets dirty. Plus it's an easy thing to inspect so it should definitely be high on your list of things to check.

Whatever code it's throwing will tell you more though, so that needs to happen as well.

 

I checked the battery cables and they were a little loose but just barely. And the other day the car started up just fine and ran and shifted with no problems throughout all gears but when I started it up about two days later it was happening again.

 

If a battery cable is even the TINIEST bit loose it will cause all sort of electrical malfunctions, you definitely shouldn't be able to twist the battery posts at all.

 

i disconnected and cleaned both cables and terminals and reset the ecu and the got no difference.