Hi all...Hoping you can help me...the tachometer on my 89 Maxima (420,000 miles) is pegged all the way right, just past 8k RPM. I was hoping there would be a way to fix it maybe without taking it out of the dash? it still has power and can move because if i accelerate quickly and let the RPM's climb high (dont know how high, obviously), the tach jumps up to like 6k and slowly climbs down (the lowest ive gotten it is 5k) until i shift, at which point it drops like an anvil back to its original setting. I've attached a picture to show you all...like i said, its not pegged at the stopper...I was thinking if i kept revving it the tach would fall back to where its supposed to be and work again, but i dont know how much im revving it so that scares me..also, i was thinking disconnecting the battery would do the trick as well...

 

The ECU has a rev limiter so it's impossible to over-rev the engine even with a broken tachometer, because the ECU and the tach both get their signal from the distributor and aren't affected by each other. I once installed my cluster without the clear cover, and deliberately flipped the needle to the right all the way. I had to get going pretty fast before it eventually re-aligned with the correct speed.

So you might just not be revving high enough.. You might just have to get the thing to bounce off the rev limiter which should be able to grab/recover the needle.

 

Sounds like fun OP!
Make sure your engine has reached operating temperature before you go WOT.

 

might be something with the gauge itself, mine did the same thing. it would read normal for a second then peg out and thrash in both directions

 

Yes it definitely sounds like it is the gauge itself. I would remove it and get it checked out if I were you. I've never heard of running the revs up to free the needle lol sounds a bit extreme to me. But who knows!

 

Lol. I was thinking about it. But thought against doing it on an engine with 420k miles on it lol. For some reason, I never drove this car hard and you can tell by the way it doesn't want to rev. My other cars see redline almost every day. But if you all think it would be ok, I will do it. Now I just need a day warm enough for it to get to operating temp. Lol. (She doesn't like to get far off cold unless its above 70*) ill report back when I get a chance to do it. If it doesn't work I may or may not take the dash apart. I just wanted it working because I like to know things. (I wish manufacturers put oil temp gauges instead of coolant temp...or both. )

 

doesnt want to rev because VG30E make their power on the low end. if you want you can try plugging in another cluster to see if it fixes the problem but it never bugged me enough on mine to dig into it

if you want a oil temp gauge you can wire in your own aftermarket one

 

You can rev it that high in neutral... If you have an automatic the transmission tends to upshift a few hundred RPM short of redline. not want to let you in gear if you have an automatic (upshifts are short of redline)

 

Luckily I have a manual transmission .(clutch replaced once in 420k miles ) I haven't had a change to do it yet. Haven't driven it recently. It has been nice out so I've been driving my camaro.

 

The alternative is, if you would rather fix it (or try to fix it) without revving to redline, is to unscrew a few panels and take the cluster out, in roughly this order:

Driver's knee panel
Button/switch panel (both sides of steering wheel but actually one piece)
Steering column shell
Black panel around radio
Black dash panel that has 3 a/c vents + clock
Cluster itself

 

So I hit the rev limiter today. Couldn't recover the tach . But, this car is really fun to drive hard! I have a feeling it'll be seeing a lot harder driving now . it seems to like it. Since I hit redline (I saw some white smoke) now it seems to run better with more power. Good ol Italian tune up. Probably blew years of carbon out of the engine (hence the white smoke).

 

unless you blew your head gasket hopefully not

 

Lol. It's not a blown head gasket. I know those like the back my hand. It was a tiny puff of white smoke the first time I hit the redline. The next 10 times no smoke. And no smoke at idle either. Exhaust smells fine. Checked for bubbles in the radiator, none there either. I'm confident it's not a blown head gasket.

 

When did you change your clutch? I'm at 310k with no signs of slipping.

 

its not always just bubbles when its idling, the headgasket in my Crown is just starting to go but the only symptom is it starts flooding coolant into the reservoir if i go past 150kmh. otherwise it acts completely normal. i would keep an eye on it