hahuang65 Posted August 21, 2025 Posted August 21, 2025 My tachometer on my new build seems stuck at 8k+ RPM. I didn't notice until after I started the engine, but it looks like, when it arrived, it was at 9K RPM (see pics) When I started the car up, I vaguely recall that I saw the tach cycle/move... but now it's at 8k-ish RPM. I tried the dipswitch toggles... I had 1,2,8 on, and so I flipped down 1 and 2, but that doesn't seem to have changed anything. It's getting power as it lights up and the battery and handbrake indicators work. However, as RPMs change, the tach doesn't move. Wondering if anyone knows if there's anything else I can try besides get a new one. Also any recommendations on a tach I can get here in the states, even just as a temporary one so that I can go get inspected/titled while waiting for the warrantied one to come in. I feel like with customs and tariffs being what they are, I'd be in for quite a wait. PXL_20250820_160632876.mp4
hahuang65 Posted August 21, 2025 Author Posted August 21, 2025 Just noticed @MV8 posted this Is this relevant to my gauge on a new 420R? I thought it was supposed to be 1,2,8 on or only 8 on... but this suggest 1,3,8 on.
MV8 Posted August 21, 2025 Posted August 21, 2025 In your mirrored pic, I see 1 and 2 are ON. I don't know anything about your reference to 1,2,and 8 ON. Make sure 8 is also ON. If that does not read correctly, try 3 ON and 2 OFF. I don't know that everything installed in a vehicle has to work in Texas but I don't know their rules. I would ask for the rules or guide they use to determine pass/fail and follow that. If everything must work, I might remove it for the inspection and add a temp cover for the opening. There are universal, watch battery powered digital tachs that wrap a plug lead to get a tach signal. They are on ebay and amazon for $10 or less..
hahuang65 Posted August 21, 2025 Author Posted August 21, 2025 3 minutes ago, MV8 said: In your mirrored pic, I see 1 and 2 are ON. I don't know anything about your reference to 1,2,and 8 ON. Make sure 8 is also ON. If that does not read correctly, try 3 ON and 2 OFF. Yeah, my dealer told me if 1,2,8 are on, flip 1,2 off... and if only 8 is on, flip 1 and 2 on. That picture I posted is how I found it so I flipped 1,2 off. I couldn't see 8, but I should take the tach out and double check. 4 minutes ago, MV8 said: I don't know that everything installed in a vehicle has to work in Texas but I don't know their rules. I would ask for the rules or guide they use to determine pass/fail and follow that. The inspection place I called told me that it's best I should have everything working before I go to them... I can try to call around, but the inspection places are just anywhere there is an ASE master tech, and they sign off on my paperwork. 5 minutes ago, MV8 said: There are universal, watch battery powered digital tachs that wrap a plug lead to get a tach signal. They are on ebay and amazon for $10 or less.. What's the plug lead I can use in the Caterham? is it already wired to the existing tach? Any links to these, mostly cuz I don't know what I'm looking for.
MV8 Posted August 21, 2025 Posted August 21, 2025 The State regulates the mechs who perform the function. The State will provide the mechs with guidance that should be available to you. Figure out where you are going them talk to a mechanic, not the counter salesman but he is correct; it is best is everything works. Here is an example of a tach and hour meter for lawn equipment. The one wire spiral wraps around any plug wire. It doesn't matter which one. May still read high or low depending on settings on the tach but it will indicate an rpm: https://www.ebay.com/itm/297337893643?_skw=digital+tachometer&itmmeta=01K36VFKG6SK234HW92X66BAT4&hash=item453ab8330b:g:JaMAAOSwNkNmKGGZ&itmprp=enc%3AAQAKAAAA0FkggFvd1GGDu0w3yXCmi1dMJ40KGz%2B2hmCeYEz4eVtl05ch3Sd7XBpxehx6rQFMMNtFTQ%2FrEobH7vwFMRPP0nkKXapNcVZr3lZOgJlUbJcp074W066%2BHAyOk3j%2Fcmt%2Bf%2Bv8cNbdHCVBPfQ7yPTK2Ecs3aWBXeU5wBdODvXG4Q%2BfXD1e1IhiJQ%2BJleJdau4%2Fbyn0A%2BVvtAxCdGTbJ8jskiaAlMJdFaOzo6M11T9j8qbgoTwx%2BpoiTilj19W1Kr8rgTD5y7fY13QeE0qeX89euWM%3D|tkp%3ABk9SR7q4vtuZZg 1
panamericano Posted August 21, 2025 Posted August 21, 2025 Tach is not a required item in Texas, and inspectors do not check accessories that are not on their list. Safety is pretty much out the window in Texas now, so verifying your VIN / chassis #, etc. is the main deal. Horn, all lights, brakes, muffler, steering?etc.
KnifeySpoony Posted August 21, 2025 Posted August 21, 2025 Your issue is not consistent with incorrect dip switch setting imo. I think you have a defective tach. I just replaced mine for incorrect clocking issues after a few years. They seem to be of low quality...
hahuang65 Posted August 21, 2025 Author Posted August 21, 2025 49 minutes ago, panamericano said: Tach is not a required item in Texas, and inspectors do not check accessories that are not on their list. Safety is pretty much out the window in Texas now, so verifying your VIN / chassis #, etc. is the main deal. Horn, all lights, brakes, muffler, steering?etc. Yeah I've found another inspector who said it won't be an issue..So I'll head over there next week.
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now