TreePatrol

hello all i just created this new account to try and get some help with my rig. i have a 1985 4runner efi. i had recently wrecked the vehicle and while so had overheated it and blew the head gasket. machine shop said it had been overheated before me doing so and said i was better off with a new head. so i got a new head. new timing chain which came with fancy new cover. had sent a stick through my radiator so i got a brand new aluminum radiator with 14 inch electric fan. got ecverything back together turned it over and broke in the cam. i still didnt have all the vac lines connected cause a few plastic pieces broke and i am still getting things for the truck but it was running great! i drove it for about 45 minutes then while i was taking a turn through an intersection (a VERY bumpy ˟˟˟˟ty section of road) i started feeling it surging. i pulled over and in neutral it would rev up to redline just fine. but then in gear it would not go over 3k. it was jerking and surging and eventually started popping and backfiring. i had to drive it 14 miles back home like that. i got all the vacuum lines connected, and re did the timing. it idles and revs in neutral just fine. driving it now, its a little better but its still cutting out almost like a small misfire. i know my plugs and wires are fine. but heres the kicker. turn signals, running lighs and brake lights make my battery gauge fluctuate and the rpms drop. when i turn on the headlights it kills the motor. i hadnt driven it at night so i had no idea this was happening. i looked high and low for bad connections or something that was shorting out and i cant find jack ˟˟˟˟. my batterys got 13 to 14v at idle, but drops down when things are turned on. and headlights kill the motor. other than that, it idles ˟˟˟˟ing fine lol... also when you shift into a gear from neutral, there is a slight rpm drop as well. could this be the alternator on its way out? when we have the voltmeter on the battery there is no change when i turn lights on, but you can hear the rpm drop and i see it on gauge in the cab. with the headlights on it drops to 10volts and kills the motor. anyone ever have anything like this happen before? it was running great prior to this even with vac lines plugged. sorry if i posted this in the wrong section. this is my first time here.

thank you for any help or advice!!!

Kevin

thefishguy77

iTrader: (1)

More info on your rig would help a bit. Auto or manual?

But search for the grounds. Look up big 3 or big 4 ground replacement. There will probably be corrosion hidden that you cant see. Al are you using a multimeter to check battery voltage or the gauge? You sound like you have an electrical problem so your going to probably need one. These wire get brittle when they are that age so there is a chance you have some broken wires that got damaged during your motor work. Ask me how how I know?

TreePatrol

no i believe you are right. thank you for responding. i just had my alternator tested at autozone and it passed. im going to add a few more grounds and take a wire brush to the existing ones. there were 3 that i disconnected total during the rebuild, one on the intake where the plenum meets the manifold, one coming from the alternator grounded to the power steering pump mount, and the direct battery ground running to the a/c compressor bolt. i had painted the intake and p pump mounts. i scraped it off with a razor blade but i am going to thoroughly clean them again and then add 1 or 2 more grounds.

TreePatrol

the battery in there now is a little smaller than the previous. but it is holding at 13.07. and like i said im baffled that it was running fine for that first 45 mins to an hour, and it then it starts doing this. like i mentioned i was taking a turn over this really terrible section of roadway like its really godawful for nearly 30 feet just madness and you cant avoid it, its the entire turning lane and taking that corner it started acting a fool. i got this ill figure it out ive come this far

thefishguy77

iTrader: (1)

Replace your existing grounds. They are probably highly corroded under the sheathing. You wont be able to see it unless you cut the insulation away. Mine ran fine for months. Then the wire problems showed up.

What codes are showing up. Jump the diagnostic ports under the hood and count the check engine flashes.
http://www.4crawler.com/4x4/CheapTri...CheckConnector

RAD4Runner

We may be thousands of miles away from you. Please say EXACTLY what's going on. 13.07 Volts with engine idling? Or with or without load?

Grounds, grounds, grounds...

Not just grounds.
CHECK ALL CONNECTIONS, INCLUDING POSITIVE between alternator, battery, fuse block.
Battery positive to positive stud terminal of starter solenoid (here)
Bare, shiny metal tightly agains bare, shiny metal, no less.
From battery negative to inner fender near fuse block (here), from batt neg to lower-front-right corner of block (here).

Also inspect the crimps in injector to ECU wires hiding under the intake manifold. While you're in there, I suggest you take wires that do not absolutely have to run there out of that harness and run them elsewhere to clean it up. I think Toyota ran those wires there to save on assembly cost, not to save us the work when fixing the truck.

skypilot

iTrader: (1)

I'm going to go out on a limb and suggest you look very hard at the sense wire to the alternator and battery, also I found that the big wire to the battery can be corroded, so that got replaced with a custom 4ga cable from the hot post of the alternator to B+. Its a very simple circuit but 13.07 at idle is too low, and its too low anytime. Needs to 14 or above, spec I think is 14.5. Check to see if your sense wire to the alternator is broken off, or the field wire has greater than zero resistance. Also check your engine fuse, it should be a 15amp fuse, some one maybe put in a bigger fuse to cover for other issues.

thefishguy77

iTrader: (1)

Op you have solid advice. Time to check your electric fu and see if its still strong.

RAD4Runner

Alt output ranges from 13.5 to 15.1 V.
Covered on my thread.

Nate Allan

You may also have an issue with the alternator, I see you said that you had it tested, however some shops, i.e. your chain auto parts stores, will not test an alternator correctly. Depending on the type of alternator you have there may be a voltage regulator in/on the back of it that can act correctly one minute and incorrectly the next, as this has happened to me before. I would find a nother person that maybe is more proficiant in testing your alternator but as the previous posters have said your issue is probably in a ground or a multitude of grounds somewhere, especially as you have just done some major work to the truck as well as have been an accident.

Thanks,
Nate