Ignition timing problem

CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Sun Dec 24, 2017 1:01 pm

No way, I rebuilt the starter and it cranks awesome.

What I mean by harder and harder to start is more of a chronological observation. I.E., after I do the whole ordeal with setting timing, stabbing disty, checking rotor position, and cleaning/replacing plugs, she will absolutely start.

Every time therafter, she gets harder and harder to start. After that first, perfect start and idle, it has a harder time catching. So what I will have to do is keep changing the position of the disty (rotating clockwise/retarding), every time I start her thereafter. Until, unfortunately, I run out of adjustment at the distributor. At that point, she will either catch, and immediately die, or crank until the end of time.

This is like a cycle or loop that keeps happening. I'm going to try again, this time with the replaced EFI relay, however, I have a feeling the symptoms will remain chronic.

The only thing I can think of is the air is not being pulsed in enough.
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jondee86
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Re: Ignition timing problem

Postby jondee86 » Sun Dec 24, 2017 5:10 pm

I'm always interested when there is a problem that appears to defy the Laws of Physics :)

In a long and colourfull career of kick starting assorted shitbox cars and motorbikes, I have
never found it necessary to retard the ignition to get the engine to start. In saying this it is
necessary for the ignition timing to be somewhere near correct. If the engine ran before the
problem and the timing has not be messed with, then it should start with whatever timing
it had before the problem began... elementary my dear Spock :P

The fact that you can get the engine to start nicely at least once, tells me that there can't be
much wrong with your ignition system. Likewise, if you can get the engine to idle at 3000rpm
even if the AAV is disabled or broken, it must be getting adequate intake air. So the finger
of suspicion is definitely raised in the direction of fuel.

The AE86 engine is fitted with a cold start injector and the cold start injector is controlled
by a thermo switch that incorporates a bi-metallic strip to disable the injector after prolonged
cranking. Every time you crank a cold engine and it doesn't start, you get a decent squirt of
fuel into the intake manifold that does not get burned. So it hangs about inside the cold
manifold and cylinders until you finish scratching your head, and decide to try cranking again.

Then you get another decent squirt of fuel on top of the last lot, and the mixture is super
rich and fuel is wetting down the cylinder walls and plug. You only need to repeat this a couple
of times with plugs that a bit sooty, and suddenly you don't get any spark :? Because the spark
takes the path of least resistance, and runs to ground over the surface of the wet ceramic
instead of jumping the plug gap. This is why it is important to use fresh plugs and make sure
that the engine gets good and warm when it does fire.

If you can't drive the car and give the engine a decent workout, at least rev the engine to
3000-4000rpm multiple times to generate some heat. Remember how the old school carbed
race cars and bikes used to be free revving the engine when tooling thru the pits and sitting
on the grid waiting for a start... that was to stop the plugs fouling.

Cold starts in cold weather also get maximum enrichment from the ECU because the engine
temperature sensor is reading low. That means even more fuel being sent to the engine via
the main injectors, which makes it even more important to have your engine catch and run
the first time you crank on it. The ECU also helps where it can... I would expect the the ECU
to retard timing during cranking, and then provide extra cold advance to help the engine
stay running after it catches until it has warmed up. You should not have to do this manually.

Might be worth checking that you cold start injector is working correctly... or maybe disable
it by unplugging and use a bit of "Start Ya Bastard" before cranking. That stuff has a lower
boiling point than gasoline, so won't contribute to plug fouling. The cold start injector only
squirts while you are cranking and shuts off as soon as you let go of the key.

So Merry Xmas y'all and enjoy a bit of family time if you can.

Cheers... jondee86
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totta crolla
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Re: Ignition timing problem

Postby totta crolla » Sun Dec 24, 2017 10:01 pm

Ok I just read through the whole thread again, firstly turning the distributor clockwise retards the timing and putting the engine in diagnostic mode further retards the timing and that would explain why the engine dies when you put it into diagnostic mode. Once you get the engine idling, use your timing light to set the idle timing at 16° BTDC (don't put it into diagnostic mode) When you have this basic parameter set, report back.

CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Mon Dec 25, 2017 8:41 am

Sorry sham, you're not on the same page. Whenever I set timing correct, I am not in diag mode. Once she idles and starts, she will eventually get harder and harder to start, and I will have to retard the timing further and further in order to lean the fuel mixture. It is a downward, failing trend of degradation..
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totta crolla
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Re: Ignition timing problem

Postby totta crolla » Mon Dec 25, 2017 11:32 am

You make it sound like a quiz and someone is not even in the same library....

CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Mon Dec 25, 2017 12:11 pm

LOL, just come down to the sunshine state mate. I won't pay airfare. :lol:
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jondee86
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Re: Ignition timing problem

Postby jondee86 » Mon Dec 25, 2017 12:30 pm

CloudStrife wrote:...and I will have to retard the timing further and further in order to lean the fuel mixture.

Sorry... I fogot to mention that changing the ignition timing does not affect fueling.
The two things are quite independent, and the only effect of retarding the timing will
be to reduce the amount of torque and increase the amount of fuel wasted.

When a car is driven with severely retarded timing a lot of combustion takes place in
the exhaust. Results in a really hot exhaust... glow in the dark hot :)

Cheers... jondee86
Give a person a fish, they eat for a day. Suggest they search before posting, and they learn a skill for a lifetime.

CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Mon Dec 25, 2017 4:15 pm

Ah, my fault. I guess I was getting confused with carbs. I do miss my carb bikes where all you needed was a dangerous can of ether to spray in the intake to "kick start" her :P)

So then the only thing I can see is that I'm just getting fuel-soaked with my CSI. I guess I can read through the pages in the FSM about it, but impedance wise it checks out..
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CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Mon Jan 01, 2018 12:12 pm

I re-did everything and she still wouldn't start. I gave up and it's going to the shop once brakes are on.
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mad_86
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Re: Ignition timing problem

Postby mad_86 » Tue Jan 02, 2018 3:50 pm

Sup im in the Miami area til friday shoot me a dm if you want some help ,

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Re: Ignition timing problem

Postby scalpel » Tue Jan 02, 2018 4:05 pm

which shop you taking it to?

how many fl members are there?

CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Tue Jan 02, 2018 7:41 pm

LOL mad 86, I thought you were in England.

I'm pretty sure it's the distributor. There really is nothing else it can be at this point. I just want someone else to tell me that before I shell out the cash for another one.

I'm near Tampa.

Scalpel, I have a few shops in the area I like. RPM motors and a local NAPA shop are what I feel most comfortable around.

And probably not too many. It's too hard to find a decent GT-S around here. They're all trashed or stolen VINs.
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mad_86
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Re: Ignition timing problem

Postby mad_86 » Tue Jan 02, 2018 9:42 pm

Im from LA area but visiting miami i thought you were south florida... :lol: lol yeahh tampa too far.

Corollas are actually pretty f**kin simple, compared to most vehicles... if your dizzy was the problem it will probly never start at all, but yours start ..probly timing

CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Wed Jan 03, 2018 12:33 am

Well actually now its not starting at all. It makes no sense, I know I set the timing proper. It's really not that difficult to do on the 4ag.
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Rogue-AE95
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Re: Ignition timing problem

Postby Rogue-AE95 » Wed Jan 03, 2018 4:12 pm

I'm also in the Tampa Bay area of FL. But I don't have much experience with this kind of diagnosis (and I don't have an AE86).
'88 Corolla All-Trac

CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Wed Jan 03, 2018 10:28 pm

We should meet up man. I'm in Hernando, so I'm about an hour north probably from you.

There is another dude in Ft. Myers that comes up sometimes.

Would love to ride in a proper all-trac :)
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CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Thu Feb 22, 2018 9:04 am

Shop found that the fuel pipe that delivers to the fuel filter was bent.

Also that the fuel was old and brown and nasty.

I forgot it was over a year old lol. But they set the timing again. Seems like it's running alright now.
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CloudStrife
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Re: Ignition timing problem

Postby CloudStrife » Sat Feb 24, 2018 10:17 am

Does anyone know of a cheaper alternative to dealer sourcing the fuel pipe? It's almost 300.00...
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mad_86
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Re: Ignition timing problem

Postby mad_86 » Sat Feb 24, 2018 2:00 pm

You can make and run your own hard lines ,, its simple just
Gotta do it right so no leaks , theres diy on youtube how to make and flare the lines or you can cut and replace just that section with rubber fuel lines and two clamps

davew7
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Re: fuel line

Postby davew7 » Sun Feb 25, 2018 3:35 am

If you do replace a section of your hard fuel line, make sure the replacement hose is rated for EFI pressures. Davew7

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mad_86
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Re: Ignition timing problem

Postby mad_86 » Sun Feb 25, 2018 8:08 am

Yes what dave said to clarify, theres rubber hose that specially just for fuel and should have a rating on the hose for efi and are usually lot stronger then just a regualr Vaccum hose

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