Cyris426

Alright guys i have a SE and it is having electrical issues with the tach. It seems sometimes some kind of short happens and the tach will jump and bounce up and down. There are two instances of this. In the first one it simply bounces and jumps but the engine continues to idle normally and it doesn't seem to affect the engine at all. The tach bounce can be huge, as high as 4500 rpm. The other instance the tach jumps and the engine runs shitty, sounds like the rpm are jumping along with the tach, in this instance the tach jump is relatively small probably only deviates from idle 300 or so both ways. Both instances seem to be more pronounced when it is raining and the car is wet. I sometimes can control the short if it is idling. When the short is occurring sometimes it will simply do nothing to the tach, but then if i draw power such as using a window or turn signal or wipers, it will jump along with the power usage. An example is jumping every time the turn signal blinks when the short is occurring. Sometimes its at the point i turn of my signal while waiting for the light and then turn it back on as i go through to prevent the power drain and cause the tach to bounce and the engine to maybe run bad. Again usually this is not happening but it seems wires get bounced and then short and then get bounced back and stop shorting and it is aggravated by the wet weather. I hate electrical issues because its like chasing a ghost. Its been like this for half a year now and i tried a few things to fix it thought the winter but was gonna wait for spring to do any non mandatory large jobs on the car. The car did not have this problem when me and my bro swapped the new engine in. I have done a little electrical stuff on the car my self: Cut the wires on fuel pump to test, re soldered and used liquid electrical tape, the map light broke so i wired it to the battery, and i have a HEI ignition module replacing the lead J-109 with 4 simple wires all wired correctly and normal electrical tape around the ends to separate the prongs and prevent shorts. Any thoughts or ideas would be appreciated.

Thanks,
Nathan

Mr_Miles

iTrader: (1)

I'm having the same issue - mine's only done it twice and I've narrowed it down to being somewhere in the blinker, I think. I don't have an SE, though.
mine does the low idle bounce, and my lights flicker with it. runs like *** when that happens, too.

By any chance, does the blinker NOT return to neutral after you turn?

Cyris426

The not return to neutral thing is due to a broken piece. When working makes it stop blinking when the wheel turns the other way. Its in the steering column i think, my brothers broke and he got a replacement out of our parts car. Dunno what its called though.

74RX4

iTrader: (10)

Check the wires connected to your coils. Specifically the negative terminal on the Trailing (front) coil. Make sure the connection is clean and tight. The grey wire is the tach signal. If you haven't already, I would replace the negative battery cable and clean the grounding point on the shock tower. Sounds like you could have a grounding issue.

Mr_Miles

iTrader: (1)

the only reason I asked about the blinker not returning, is because the same day that piece broke on mine, is the first day my car went all crazy like. i imagined that one of those tabs just wedged itself somewhere and was causing the issue. when i replaced mine, i found one of them, but the other is still in limbo lol.

I'll double check my coils again, make sure i have good connections.

MacNeil

I'm having this same issue, I recently Tore down my starter and greased the solenoid. After putting it back the battery was dead and I had to jump it, the starter worked fine now (it was not engaging earlier) but the Tach will jump randomly when I press the brake and engage the brake light or use other electronics. At first it didn't affect the idle or engine but after driving about 1km the engine lost power at 3k rpm and sounded like a semi down shifting. It then will cut out on all other gears at variating rpms. help?