After working on my car yesterday I ran into a strange problem (Fixing a distributor). Whenever my car goes above 900rpm all the lights (head light, tail light, dash light, anything that has a bulb) starts to fade in and out like a pulse. If it's below that mark it's fine, but it even happens when I drive. Also, my speedo stopped working and obviously my cluster stopped counting miles. Sometimes for a second or so it blips up and acts normal then shoots back down. I reset the ECU a million times. Any ideas? I'm sure it's electrical but I wouldn't know where to really start. Thanks h-t

 

i would check all of your grounds first.

 

Start by checking all the main power and ground connections.

MM&Y of car??? 94

 

98 honda civic dx hatch. D15b7 bottom d16z6 head. Sometimes when I'm driving the speedo blips and works for about half a second then shoots down. Are there any grounds under the intake mani? My buddy was looking under there

 

Checked my grounds and they seemed to be fine. I cleaned most of them. Any ideas? Also sometimes the car like "switches" modes and the speedo goes crazy but the car runs like crap. If I flip the car off and on it goes back to no speedo, pulsing lights, but the car runs fine.

 

Have you checked the power connections? 94

 

Tighten your battery terminals but take them off first then clean them.try that for now.

 

Also check the ground on the thermostat housing.See if its loose.Its next to the sensor on the thermostat housing.

 

cleaned the battery one, terminal was tight. I also switched distributors, same problem

 

What do you mean by power connections exactly? My car had done this before, it was from rubbing of a bracket I think, on the harness but I checked and took that apart and it seemed all well.

 

The main power connections are batt. pos.(+) post and terminal, batt. to fuse box, [engine bay] alt. charge line at the alt. and the fuse box, the main fuses in the engine bay fuse box.
All the above should be removed, both contact surfaces cleaned then reconnected.

Once above is done, I would have a proper load check don4e on the cars charging system. 94

 

I had a load check done on the charging system and it was fine. I have cleaned most everything also. All the grounds and such were tight. If it was a short would i have to take apart the loom and what not in order to find the short, or where should I start looking considering that it has to deal with the VSS since I still have no speedo and the lights still pulse. Thanks

 

changed the alternator and battery, still no luck

 

Still having problems. Could an alternator really cause my speedo to not work? Has anyone else had this pulsing light problem?