Lets talk about this annoying hot start problem...

are there any KNOWN fixes for this?

the person who had my SVX before me wired in some relay and it simply does not work.

ive searched and read thru old posts that suggests wiring the starter directly to the battery can correct this? any proof?

another idea i had was a starter button.

[Electrophil]

Some will not agree, but I'm saying it works through experience. Replace the stock wiring to the starter with new stock wiring or one gauge better. That's it... It works.

No relays, no fancy alternator configs, no direct runs bypassing an electrical system designed by Electrical Engineers sporting fancy degrees and 4 years of advanced math classes.

The wiring is old, and positioned in a car with excessive transmission heat. It gets brittle and cannot carry the current it could when the wiring was a couple of years old. And it's amazing how we all think it's ok to replace a temp sensor with like kind without a second thought, but wouldn't dream of replacing sections in our harnesses without an elaborate rework of the entire electrical system.

And it's really not that hard to do, if you use the old wiring as your "pull line" for the new wiring. Unwrapping can be time consuming though.

Now I'll grit my teeth and prepare for the attack from the back yard engineers.

[Earthworm]

Wasn't it already determined to be the ignition switch wearing out/falling apart?

[nordique14]

Replacing the ignition switched helped a lot, but not completely.

When I first started having starting trouble, it was only on restarting a hot engine on a hot day. Eventually it began happening more frequently so it would sometimes happen with a cold engine. Replacing the ignition switch seemed to cure it. I say "seemed to" as on a couple of very hot days after running the car hard, I had trouble if I tried restarting within, say, a 1/2 hour of shutting down.


I agree that the wiring in the SVX is underdone and an upgrade would be helpful. But I would say that the switch is a good thing to replace and see how much it helps.

--Matt

yeah, those are the same symptoms i am having.

warmer days, short trips in the car say to the store or whatever...1/2 hour later im cycling the key 40 times to get it started again.

the previous owner said he installed a fix for it but it might as well not be in there at all, in short - it doesnt do anything.

so start with the ignition switch? i think that was already replaced once in the cars life - it has an STi key for the ignition and the normal key for the doors/trunk.

any others? and thanks to the people who replied.

[SVXRide]

I'm with the "replace the wiring" train of thought....there is a lot of heat generated under the hood and it eventually turns all of the wiring's insulation to something resembling a brittle twig (this includes the wire leads on the knock sensors, the wiring to the alternator, etc.). Adding additional grounding straps doesn't hurt
-Bill

[RojoRocket]

There's also an ignition safety interlock switch that may be at fault, but not necessarily related to "hot-start" problems. Are you saying that the key turning does absolutely nothing on attempted restart? When I've rarely had this happen I've reselected park and released and reapplied the brake pedal firmly, usually with success.

Glenn

this is a 5 speed using a cable shifted legacy trans.

during attempted restarts, when hot the starter will click 20 times before it decides to start.

[Beav]

If the wire has some really bad resistance or corroded terminals it could be the culprit. I'm here to tell ya that a 14ga wire will carry enough current to start a car. Trevor and I bantered around over this a few years ago - he's a retired EE and knows his stuff. A couple weeks ago a couple buddies and I removed the battery cable from a car. Yeah, the big, heavy one, and replaced it with a 14ga wire. Now, granted it got hotter than hades but it still started the car, just a hair under 200amps. So I reckon a 16ga wire can manage to power a starter solenoid. (BTW - this negates the value of the infamous 'alternator mod'. As long as you have good, clean connections and undamaged wire the OE wiring will do just fine.)

A month or so ago a friend of ours was having the same starter no go-go problem on his SVX. I did a quick voltage drop test by placing one lead on the positive battery terminal and the other lead on the small terminal of the starter solenoid - .12v, a reasonable reading (voltage drops on most 12v auto circuits should be less than .5v) Leaving one lead on the battery + I moved the other lead to the battery cable end at the starter - 6v was shown on the meter. This means the cable was losing half the battery voltage to the starter (12-6=6.) I then jabbed the lead into the battery cable about three inches downstream of the battery terminal and still had the 6v drop. Turns out, even though it couldn't be seen to look at it, the cable clamp at the battery was bad. Total diag time = 2 minutes, no parts required.

Now I'm not saying you have a bad battery cable or that overlaying a new wire didn't work for E'phil. I'm just trying to teach everyone the quick, easy and proper way to find an electrical fault. Some time ago I published the add-on relay as a cure for a problem I was experiencing. Since my particular no-start condition was sporadic I couldn't rely on a voltage drop test because it only occured maybe once a month or so. I wired up the relay to ensure 12 volts was getting to the starter solenoid trigger terminal. As it turned out quite a few others have fixed their similar problem this way, but it didn't work for others.

If y'all need some more discussion to understand voltage drops, and why measuring ohms/resistance doesn't mean much on a car's circuitry let me know.

so...replacing the terminal ends might be a good place to start?

[Beav]

No, performing a voltage drop test would be a good place to start.

Starter solenoid contacts.

[TomsSVX]

just wail at the starter with a hammer, if it is a quick fix, get a new starter Seriously though, give the selenoid a quick tap while someone is trying to turn the ignition. Try it a few times as the first is not always a success. If it turns over after tapping it your starter has a "dead spot" in which it will not turn over unless forced to(hammer or wrench hitting it) This is usually a good time to replace the starter.

Tom

[ShiuludeSVX]

I agree with Tom. Tapping will show where the problem is, and you probably find out that having someone rewind the starter, or a rebuild will do it.

There are exceptions, like the Tranny interrupt mentioned before. But manual puts that down.

But I think Tom has it.

[oab_au]

I have written this before, but it is still the same. The US car seems to have a few series switches in the solenoid circuit, that the Australian model does not have. These switches have sliding contacts that have to carry a high current to pull the solenoid armiture and starter gear in, to operate the starter motor itself. Toms hammer methoid, shakes the solenoid armiture loose, so that it will slide up to the motor contacts.

The starter solenoid circuit, has two sets of windings in it. The first action is to apply power to a low current, hold-in circuit, and a high current pull-in circuit. The pull-in circuit also flows down through the starter motor itself, to start the motor gear rotating, so that it will mesh with the ring gear teeth. When the solenoid armiture does pull the gear into mesh and reaches the end of the solenoid it switches the main current to the starter motor on, it also switches the pull-in circuit off, so that only the hold-in circuit is left in operation.

This can be measured, by removing the main cable from the starter solenoid, and measuring the current flow to the solenoid operating terminal. This will be around 30 amps. As the series switches in the circuit wear and arc from this current, their resistance will increase, till they can't carry enought current to pull the solenoid in,( unless you use Tom's hammer fix to shake it along).

If a relay is fitted properly, it will only take 100mil amps, through the solenoid wiring circuit(ign key, gearbox switch, ect) to operate the relay, then the relay can supply the high current to operate the two solenoid circuits.

Harvey.