What's up everyone?
It's been a while. The car has been a nightmare. It's going for paint yet again due to bubbling.....
I digress.
I have another issue that isn't a huge one, just a nuisance.
I have the full digital dash with the digital oil pressure monitor. It usually reads 4 or 5 bars out of a possible 8 which is normal. I've noticed that the defroster will make the readout read 1 bar higher when it's on. It's done it for as long as I can remember. Does it in drive, park, reverse, under a load etc....
Oil pressure is good according to a manual gauge (21 PSI @ hot idle).
The car has the EATC system and I swapped back to the full sending unit and not the dummy unit a couple of years back.
Any ideas?
Burn it with fire...... :-)
sorry, i have seen mine switch up / down with the AC going or even heat but not a steady extra bar. sounds just like your issue but a little leaner.
Could be a case of thermal changes. Does it do so immediately or does it take some time before the bar gets incremented? When you turn off the defroster, is the effect on the bar immediate or does it take several seconds? Does it matter if the ambient air temp is hot or cool? If you pull the cluster out of the opening without disconnecting it, start the car and run the defroster, does it still do it? If so, what happens if you use canned compressed air to chill the cluster? If you check the wiring for your cluster, does the voltage on the pin coming from the sensor change when you turn on the defroster?
I hope this might help you figure it out.
The delay is less than 1 second. Ambient temperature does not change this. I do notice that on humid days -- regardless of temperature it will go to the lower reading. This gauge like dry air. I haven't pulled the plastic sheathing back that I put over the wire some time ago. Perhaps there is a bare spot.
Soon enough. BTW -- car's gonna need a full repaint. Bondo never cured correctly. We picked a couple of bubbles. Cottage cheese underneath.
Dude WTF!!!!!!!!!! You need a new bodyman. Yesterday. That's disgusting. How much mud is on there!? I sure hope you haven't been paying big money for this so far....
Looking at the 87 EVTM, the only thing electrical that is unique to defrost is the door actuator for the air plenum. The door is operated by a motor. The motor has a switch that signals when the door is open or closed to the control module. If this switch fails, the motor will try to keep running after the door moves as far as it can go. A stalled or locked armature motor draws more current than a running motor. This extra load may cause a voltage shift that is affecting your oil gauge.
This my best guess.
If I recall correctly, such a failure would throw a code on your ETC display. It has been almost a decade since I yanked the ETC out of my '88 LX, but I do recall it throwing a diagnostic code indicating a inop door.
Apologies. When I referred to the defroster, I meant the rear window defroster.
Now that is a horse of an entirely different breed, let alone color. The rear window defroster is a low current device anyway, unless there is something wrong with the wiring between the switch and the rear glass. I would think a short would blow the fuse, but without an EVTM, I could not begin to tell you where to start looking, other than to advise that you disconnect the leads to the rear defroster, hit the defrost switch and see if the gauge still acts the same way. If so, it isn't the defroster itself, but more likely in the wiring or the defroster switch. Of course, it could also be completely normal. The way that the digital dash knows what to display is by voltage alone, so it could be that with the engine idling, the alternator simply isn't putting out enough current to operate everything and you see a voltage drop, which your particular cluster might be sensitive enough to display the change in voltage.
Ignition switch, perhaps...or the wiring at the ignition switch.
Or maybe just change out to REAL GAUGES. ;)
I actually DID find the culprit in this. It was a wire connector for the wires that run directly under the battery tray. It had become corroded and was allowing stray voltage all over the place. I removed it and hard-wired everything that runs underneath the tray and rewrapped it all to keep it safe from the elements. Between this and new grounds all around, I've been issue free electrically for a few months now.
interesting post,,
and to your example,, more paralleled grounds are in my future as well.
I never kicked a code on the eatc though,, my eatc simply flashes all the "F"U lights at me randomly. a restart of the engine usually cures it.
Thank you for posting an actual update, wish more did.
I was wondering if this cluster needs better grounds. Whenever I switch on the HVAC fan, my Volt gauge drops a bar instantly. Does your guys do this??
Yup, the blower motor draws a good deal of juice.
hmm,, mine does not, although I have the relay mods and No-oxide on all my connectors
none of my power is going through the ignition switch or headlamp switch... steady rock solid
Mine will show 5 bars on my digi dash with no accessories. Turning on the blower will drop it to 4.
Hmm mine does not do this. If I turn the blower or A/C on the same 5 bars are illuminated. Now if I turn the headlights and blower on it goes down to 4. Either I have really good grounds or my voltage gauge is a liar. Probably the later one.
Blower and lights is 4 here as well. No idea. My grounds are all beefed up as of a few months ago....