Cruise control/turn signals acting up

[etlsport]

noticed it about a week ago, on the highway at cruising speed when I would go to change lanes and hit the turn signal, my rpms would fluctuate 150-250 rpm. doesnt happen if im off the throttle, doesnt happen if im accelerating, just when maintaining speed.

at first i thought that it was just me giving a touch of gas anytime i hit the turn signal sub consiously, but i tried it with the cruise control on to eliminate that possibility, and as soon as i hit the turn signal, the cruise control turned off. i dont remember that happening in the past.

i really have no idea what would cause this.. im going to try going harness by harness and disconnect, grease and reconnect to see if that helps, but other than that im stumped..

any ideas?

[Ldub]

The first place I'd look would in an area known to cause other electrical gremlins...where the wire bundle passes through the front bulkhead on the drivers side of the radiator.

Just a WAG..., but it's been a known cause of problems for Anita & others in the past.

.

[tom4bren]

Check the ground on your trailer wiring harness. I had all kinds of gremilins when I had a bad ground there.

[BigMeatVX]

My guess is that the turn signal is shorting somehow accross to the brake light, and sending power back up the brake wire....which "tells" the Cruise controll that you've just hit the brakes...Of course, this signal causes the cruise controll to "cancel"

Also, since it is doing this with the cruise controll off...I am VERY sure that it is indeed sending the + signal back up the brake wire....As this is causing your torque converter to un-lock at highway speeds. (The RPM flux you are seeing)

Do you have aftermarket signals or LED conversions on any bulbs? Also could be trailer wiring as mentioned....

[etlsport]

youre right on track bigmeat.

i was messing with it more today, when in park or neutral, the turn signal actually activates the shift lock release

i have converted the rear side markers to turn signals, added extra brake/tail lights and have LED tail lights... AND trailer wiring so its a nest back there

i actually already checked all the connections, everything is tight, i think my first move is to remove the trailer wiring all togehter and see if that fixes it. removing both LED tail light bulbs moved the problem from one side to the other, but once they were both removed, it continued on the left for a while and not the right, then switched to the right and not the left.


im leaning towards a short because ive had these mods for a while with no problems, the most recent additions were the LED tail light bulbs, but thats been 4+ months now...

will keep updated

[etlsport]

ok did some more experimenting.

its definitely related to the LED bulbs, which is strange though, I dont remember it happening right away.

I replaced the LED tail light bulbs with regular 1157s and it went away completely. Then I tried just one LED bulb and one regular 1157. Problem still gone. Switched LED bulbs, still gone. Then did the same procedure again, but with the regular 1157 in the other housing. Same results

The only time it happens is if I have two LED bulbs in the tail lights. I'm thinking I'll try a load resistor like on turn signals and see if that makes a difference. I'm thinking that the LEDs just may not put out enough resistance (so grounding through the bulbs instead of frame) I'll try that, although I'm not real confident. I'm thinking the current will just go through the bulb and skip the resistor (path of least resistance)

at least I can fix it if i want. but for now the LEDs stay, they just look too cool. If I cant figure out how to make it work I'll have to go back to regular 1157s though