TheRupp

Would putting a more powerful alternator in the car help this problem? I know it's a strain sometimes when I have the headlights on to close the windows and the sunroof at the same time... really annoying as sometimes they do a pinch-protection thing and go back down halfway

dallison

i pulled into the garage and had the car running and was watching the headlights. they were pulsing pretty good. i turned off the car and obviously the pulsing stopped.


could it possible be a plug wire???
i know it sounds dumb but is it possible?

dallison

i checked the ground connections and all seems ok.

so i started teh car and watched the lights. the 1st 5 seconds or so, no problem then it's like something electriocal kicks in and the lights start to flicker

TheRupp

AC compressor or fan maybe?

dallison

the fan and climate control was off

lexusls430

Just for reference, my 2000 solara did this and my 99 solara does it. I thought it was a problem but i guess its not since both of my cars have done it. I have heard that upgrading to the 130 volt Highlander alternator fixes this problem

dallison

i just replaced the alternator that contains the voltage regulator too

dallison

i checked all grounds and fuses in the engine bay and all is well.

i replaced the ground wires on the passenger side that have the disconnects in the middle to make sure that the connection wasnt bad. i used thicker wire also. it did not help so i reinstalled the old ground wires.

what next?

dallison

update............................




i started to pull fuses in the engine compartment. i started to pull a few at a time. keeping the ones that are important to keeping the motor running, i pulled things like the radio, heater etc.

then i finally got to the a/f htr fuse.

this is the air fuel ration sensor


once i pulled it the lights were normal and i had no pulsing, i reinstalled it and it pulsed.

i tried it a few times and this seems like the culprit.

any help with this discovery would be helpful

dallison

anyone with more info?

lexusls430

I remember reading something about this i think. Both A/F sensors come on at the same time causing the power loss. I think they are supposed to go on one at a time so its probably a flaw. I dont know if there is a fix.

dallison

interesting

dallison

ok tonight i unplugged both o2 sensors, one at a time, and still had the pulsing.

i then unplugged one sensor at a time that i could reach, and still nothing.
i unplugged the harness on the alternator and then the tps, and still nothing.


i unplugged the fans and prob a total of 10 -15 sensors w/o any luck.



i then looked at the fuses/relays connected to the battery, i located a a/f htr relay. i unplugged it and the pulsing stopped.

so i am getting somewhere. so i wrote down the info on the relay and found one on fleabay. i offered $6 from the $10 buyit now price plus shipping of $5 so hopefully it will cost me $11



does this sound like a relay could be bad?? esp after i disconnected these sensors?

dallison

dallison

well, it's not the relay, i tried the one in the wifes' 4runner