Hey all, I have a 95 prelude SE with an h22a motor swap in it. Motor has about 36k miles on it and the body has 189k. just recently got everything done and I put about 600mils on it when the tach and speedometer started jumping wildly. I pulled over and let the car cool off a bit then started up and had no problems for probably 30-40mins. It's now happening more frequently I've found that up until now I could either dim down the dashboard lights and it would start working or go into neutral and hit the gas and it would come back on. When I start it now its working until I either go into 1st and start to move or I turn on anything electrical (windows, stereo, etc) could this be a loose wire or maybe the alternator isnt supplying enough power? I have a check engine light on for the map sensor but nothing else comes up. I'd appreciate any help I could get on this.

 

is it only the needles for tach + speedo that dont work? does everything else work fine, or is your car having a loss of power or a mechanical problem?

if its just the needle not moving, i would take a look behind the cluster. the tach not working could be related to something previously installed that taps into that connection, like aftermarket gauges or a remote starter. but if youre saying the speedo too, your problem could be behind the gauges. pull them out, its usually easy to do, im sure you can find a write-up on here.

fix your map sensor too, very important piece...

 

Had cleaned the battery terminals and the car was starting ok again but a day after that the battery has no power again. taking the car in to have everything tested today. As far as the dashboard goes the other lights will dim when the needles jump but they work fine even then. the back light on the tach and speedo stay light the whole time.

 

Check your dash harness grounds.

If your batt. goes dead when car is not running, [ign. off] you have a parasitic draw, something is staying on and drawing power from the batt.
If you have a 12V test light you can do a basic parasitic draw test yourself...
https://honda-tech.com/forums/tech-misc-15/simple-batt-drain-test-%5Bparasitic-draw%5D-2962333/ 94

 

Took the car down to a certified mechanic after I had virtually no luck. He tested my battery and alternator. He said the battery isn't the right size for the car and is garbage as well. Going to get a new battery and see if everything keeps happening. He told me that because the battery is so bad that it could affect the amount of power the alternator is supplying everything else. As far as something sapping the power while its turned off I believe it has a broken car alarm in it. At one point my spare keys weren't working. my brother clipped 2 wires in it and theyre working now so I'm taking console apart to find what it is he clipped.