AE86 only COLD starts.

User avatar
Bib
Club4AG Regular
Posts: 19
Joined: Mon Apr 04, 2016 10:49 am
Location: Eastern Massachusetts

AE86 only COLD starts.

Postby Bib » Tue Oct 11, 2016 6:57 pm

I'm having a problem that started last night when I was messing around trying to fix my blower (which I finally fixed.) All I did was cut some electrical tape off the wiring harness to find some wires. Now, my AE86 only wants to start cold.

For example: When I start it and then shut it down after 5 seconds of running, if I try starting it up again, it'll just keep cranking. Let it sit for 5 minutes or so, it'll start. Regular cold starts are easy, motor fires great.

The COR is working during this. I'm not sure if I'm getting spark or not, I'll have to check later. On top of this, the headlight motors seem to want to raise slightly when cranking.

There's no CEL code.

When started, the car runs like a top. No problems running at all.

This is for a 4A-GE by the way. Any help is appreciated.

Disable adblock

This site is supported by ads and donations.
If you see this text you are blocking our ads.
Please consider a Donation to support the site.


User avatar
ToeKnee805
Club4AG Expert
Posts: 299
Joined: Wed Jan 09, 2013 8:17 pm
Location: Southern California, 805

Re: AE86 only COLD starts.

Postby ToeKnee805 » Wed Oct 12, 2016 1:44 am

if you removed your blower motor, make sure you didnt pinch any wires putting it back on. It may seem obvious but try to retrace every single step, could be that your shorting the spark signal from the ECU
1986 Corolla GT-S -- Unmolested -- Now Resto Project
1985 Corolla GT-S -- Turbo Levin Track Car
1982 Corolla 1.8 -- Sitting collecting dust

User avatar
morgan
Club4AG Pro
Posts: 873
Joined: Thu Jan 10, 2013 10:29 pm
Location: og, nj

Re: AE86 only COLD starts.

Postby morgan » Wed Oct 12, 2016 6:37 am

the Cold Start Injector, Cold Start Time Switch, COR, AFM, injectors...all are tied in together. like mentioned above, double check that nothings pinched. the wire im thinking of is brown with black dots that's tied in to all the sensors and stuff, but theres a bunch within the underdash too that are all integrated together. also, try unplugging the Cold Start Time Switch and see if it helps. the brown sensor on the front upper water neck
haha cali...i got one of your 86's and you're not getting it back.
My turd of an 86
20v swapped 86 write-up

User avatar
Bib
Club4AG Regular
Posts: 19
Joined: Mon Apr 04, 2016 10:49 am
Location: Eastern Massachusetts

Re: AE86 only COLD starts.

Postby Bib » Wed Oct 12, 2016 3:57 pm

I just did a little more testing on my break, the igniter arcs when grounded out on my strut bar but the wires won't. I have to see if they spark when starting it after the 5 or so minutes it takes to want to start again. I'll update this post when I can. Taking the car to have the windshield fixed tonight so i won't be able to look at it for a few days.

Also unplugged the cold start injector while testing it and the engine fired, so I guess that's not the problem.

Thanks to both of you for the suggestions by the way. Gonna do more in depth testing when I can.

Still thinking its a wiring problem the way the headlight kinda moves up a quarter of the way at max. That started happening a month or so ago.

Disable adblock

This site is supported by ads and donations.
If you see this text you are blocking our ads.
Please consider a Donation to support the site.


User avatar
ToeKnee805
Club4AG Expert
Posts: 299
Joined: Wed Jan 09, 2013 8:17 pm
Location: Southern California, 805

Re: AE86 only COLD starts.

Postby ToeKnee805 » Thu Oct 13, 2016 1:15 am

Actually now that i think about it a buddy of mine had almost the exact same problem. But his wouldnt HOT start. So if we drove on a long drive, and he turned his car off he was fucked untill it cooled down. For some reason his headlights would act all haywire...i believe he replaced the headlight switch. Try unplugging the switch and seeing if it still fires. No clue if the wires are tied into eachother or if they share a circuit breaker but hey its worth a shot.
1986 Corolla GT-S -- Unmolested -- Now Resto Project
1985 Corolla GT-S -- Turbo Levin Track Car
1982 Corolla 1.8 -- Sitting collecting dust

User avatar
Bib
Club4AG Regular
Posts: 19
Joined: Mon Apr 04, 2016 10:49 am
Location: Eastern Massachusetts

Re: AE86 only COLD starts.

Postby Bib » Tue Oct 18, 2016 1:13 pm

Well, I got the car back. Today it's not starting at all. There were a couple of moments where it wanted to catch, but just coudln't fire. While cranking, the headlight motors move DOWN if I leave the lights up. I did notice a ground wire started smoking when trying to crank it. Leads me to believe more that this is a wiring problem. Tonight I'm gonna go to work on it.

The car would start fine before I messed with the blower wiring under the hood. The starter is new too, I replaced that when i was doing the gearbox a week or so ago.

I know very little about wiring but I'm thinking there could be a short.

It's a wire bolted to ground A1 that's smoking. Left fender.

Edit: Wait, the wire is on the same ground as the negative battery terminal. Wouldn't ground point A be under the fuse box?

User avatar
Bib
Club4AG Regular
Posts: 19
Joined: Mon Apr 04, 2016 10:49 am
Location: Eastern Massachusetts

Re: AE86 only COLD starts.

Postby Bib » Tue Oct 18, 2016 2:38 pm

Ok, the prolem was that I had a ground wired to the negative terminal on the battery. Solved.
Last edited by Bib on Tue Oct 18, 2016 6:26 pm, edited 1 time in total.

User avatar
jondee86
Moderator
Posts: 2454
Joined: Fri Jan 11, 2013 10:21 pm
Location: Wellington, New Zealand

Re: AE86 only COLD starts.

Postby jondee86 » Tue Oct 18, 2016 5:53 pm

Bib wrote: I did notice a ground wire started smoking when trying to crank it.

When a wire starts smoking it is hardly ever a good thing ;) What it means is that
the wire is carrying more load (amps) than it should. Cranking draws a lot of amps and
that means there are high amps in both the positive wire to the starter, and in the
ground wire back to the battery.

If you happen to leave the main ground wire between the engine (close to the starter)
and the chassis disconnected, those amps will try and get back to the battery any way
they can... usually by a skinny ground wire. Skinny wires are too small to handle the
starting current, so they get hot and start smoking.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

Disable adblock

This site is supported by ads and donations.
If you see this text you are blocking our ads.
Please consider a Donation to support the site.



Return to “TECH: Corolla AE86”

Who is online

Users browsing this forum: No registered users and 2 guests