Tips on diagnosing electrical/ignition issues?

I've fooled with hard parts for years, I'm pretty much a complete newbie digging into electrical issues, particularly on a more modern car.

I've got a test light and a multitester and the shop manual. Any suggestion either general or specific in trying to hunt down the cause of a no-spark situation on an '89 Cressida? Techniques or other practical advice, things to do, or to be careful to avoid doing - how do I avoid damaging parts that are delicate and expensive - like the brain box or igniter, assuming they're both still good.

Any good books or websites you can recommend? Can I have reasonable success without strong knowledge of electronics?

Thanks.

The factory shop manual should have a diagnosis matrix for diagnosing ignition problems, including the igniter. The ECU is unlikely to go bad, and if you have checked the coil, distributor, and wire harnesses, then follow the checks for the igniter. Unfortunately, there are not a lot of checks for the igniter, it is more like "when all else fails, replace the igniter." There should be steps for checking voltages at the terminals for the igniter connector.

Have you considered:

2) Read and respond to knowledgeable advice that was already given, ie

4) Not emulating Al Kondo

Toyota MDT in MO

Guess I see this question as a distinct, more refined one than previous.

If you disagree, okay.

ie

Read it, appreciate it, it didn't necessarily get to the meat of what I was looking for. You had a similar testy coment when referring me to a previous answer you had given when I asked what could cause an ignitor to go bad. The answer you referenced didn't answer the question of what could cause an ignitor to go bad.

While I appreciate that people including yourself take the time, one doesn't always know if the answer is knowledgeable, given the amount of dissent, diametrically opposed responses and flame wars that are often spawned regarding various topics - and not just mine and not just in this forum. One takes all input with a grain.

The other issue is that new things tend to get buried in lengthening threads.

Note the "thanks" in the original post. Meant to pre-acknowledge those who make the effort to answer. I for one don't expect a personal acknowledgement of every question I answer.

Do you individually thank every response to every question you ask?

I was taught in College that an old style 'test light' can outright kill vehicle electronics by introducing either too much voltage in the case of a 12 volt light or putting too much load on IC or CMOS chips which 'can' fry them in either case.

Same for an old style VOM.

On modern stuff you need a digital multimeter to be safe.

I also believe your coil is dead from the readings you have posted. Every 'coil' I have tested that was out of the book range for readings was indeed dead. The last one's range was 400 to 800 ohms. It read 385 if I remember right and a new one that read 500 or so made the engine run again.

For your 'basic' electronic testing, the cheap Haynes manual isn't too bad. They are better on the older vehicles but give the basic readings and test points for most things electronic if they can be home tested.

Mike

Doc,

While Comboverfish is a frequent contributor to this ng, he rarely asks questions because he rarely needs to. If he doesn't know the answer, then the next step would be someone at Toyota's (dealer only) technical hot line.

FWIW, in my 15 years working for Toyota, I saw a lot more bad igniters than bad coils or bad ECU's.

This seems to be the concensus. However, is it a piece that's likely to go bad just sitting when it was previously working fine?

That's funny, Ray! This is going to sound very harsh, but the TAS resource is for idiots that don't even know the basics. There are so many idiots in this trade that TAS is an unfortunate necessity, and even more unfortunately it is geared towards the idiots, therefore empowering them and keeping the *real* problem alive. It's turned into no more than a warranty parts swap authorization service IMO.

As much as I realize that it is difficult to provide helpful tech assistance, the fact is that the few times I have called of my own volition for an engineering description of a system, I received nothing but a waste of time. I've never gotten a working description for something which wasn't outlined in the manuals and training info. It's not like I call to have them regurgitate what the service manual already states. It's not like I call because I don't understand basic pressure, electrical, and emission theories. I don't need my hand held. The last two times I was forced to call by the service manager because, as it turns out, the japlish service info was wrong, and I made the mistake of mentioning that I *might* be wrong due to the lack of info. I had already made what turned out to be the correct diagnosis in both cases, but had to waste time on the phone with people that didn't have an "answer" that I didn't need in the first place. Like I said, it's a parts swapping authorization service and the service managers love it. They can keep idiots in their employ and everything remains smooth sailing from their perspective. In those two cases I figured out the "problem" for TAS, which is pretty much all their database is about anymore. In practice it is completely useless because the info that gets stored in it is trash. Generating and technical editing service literature *in California* by English speaking natives would really help, but I guess that's why that will never happen.

The real help comes from area field reps. I would say that every one I've met is sharper than me in atleast one if not all areas, and most of the guys have much more experience. They actually break problems down in their "free" time and learn the very minute details, as a result their efforts mean real positive help for real problems in the shop. Well, guess what? Every year they are limited more and more by corporate. Frankly I don't even know what they do anymore as they will not field questions directly anymore. I have been helped immensely at least twice in the last 10 years by KC reps. Limiting their effectiveness is just one more nail in the coffin for Toyota's dealership repair operations.

This has turned into a rant that started out as a chuckle in reply to your statement. Sorry about all of the wind.

Toyota MDT in MO

The techs were complaining bout the quality of the advice they got from the TAS when I left - I guess things haven't improved much. Fortunately, the field technical specialists still know what they're doing!

Thanks for your contributions here!