1991 Accord - No Start - No Spark

Howdy.

I've got a 1991 Accord that won't start. It ran fine daily, sat parked for a couple of days, and now won't start.

- No Spark on any plug.

- Cranks just fine.

- Fuel pump cycles when the key is switched on.

- Check engine light comes on, then shuts off after a few seconds.

- Rotor turns.

- 0.7 ohms resistence across the low side of the coil (low voltage tabs).

- High side of the coil (post to ground) is open (infinite resistence).

My initial guess is that the coil is bad. That just seems so unlikely considering it ran just fine when it was parked last week. If it died while running that diagnosis would be consistent.

Any suggestions? I'm out of my element here.. I'm more comfortable with Honda motorcycles and GM/Chrysler cars.

Thanks!

-rev

Reply to
The Reverend Natural Light
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"The Reverend Natural Light" wrote in news: snipped-for-privacy@j44g2000cwa.googlegroups.com:

Definitely sounds like an open coil.(the infinite secondary resistance measurement is the glaring clue) You could also have some bad plug wires,that allowed arcing and extra strain on the coil.Or from condensation moisture built up while sitting. Time for new coil,distributor cap/rotor,and HV wires.

use of OEM parts is highly recommended.

Reply to
Jim Yanik

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I think it WAS flooded (see owner's manual for how to start) but now the coil (or is it igniter) is shot because you spun it with the plugs disconnected. When the high tension has nowhere to go, it goes internally and blazes new trails.

The flooding is caused when an injector dribbles overnight and all the fuel in the pressurized in the rail drips into one cylinder. The cure for the injector is cleaner, twice a year, or gasohol now and then.

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has way more help about igniters.

'Curly'

Reply to
motsco_

Reply to
Thom

"The Reverend Natural Light" wrote

Specs are 0.6 to 0.8 ohms and 12,800 to 19,200 ohms, respectively, so the resistance checks suggest the coil is good.

I agree.

My money's on the problem being the igniter or some other ignition part. The igniter costs under $100 from OEM online parts sites and is not hard to replace, given your other experience.

How many miles on car? Years and miles on coil and igniter? If originals or non-OEM, again, strongly suspect one of them.

When was the car last tuned up (new plugs, wires, distributor rotor and cap, fuel filter, air filter, timing check, bottle of Chevron Techron in fuel tank)? Were OEM ignition parts used?

A good site for these and other candidate problems for your situation, including further checks you can do on the coil and igniter:

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has a free online manual (with many factory service manual excerpts) for your car that also has troubleshooting procedures under the "Engine Electrical" section.

Reply to
Elle

"Elle" wrote in news:%pBbh.5635$ snipped-for-privacy@newsread2.news.pas.earthlink.net:

How does "infinite resistance = 12.8K to 19.2K ohms? IMO,infinite R = OPEN = bad coil.

Of course,he should be measuring from either one of the LV tabs to the EHT output terminal(post) for that secondary resistance reading,as the igniter will not be grounding the coil.

Reply to
Jim Yanik

"Jim Yanik" wrote

I thought his meter might not be able to register high resistances. Maye this is erroneous on my part...

Reply to
Elle

I didn't crank the engine at all with nothing connected to the high side. Entirely possible that has been done in the car's past, however.

-rev

Reply to
The Reverend Natural Light

I measured from the high tension post to ground and it read (according to my highly accurate Radio Shack auto-ranging digital multimeter) to be completely open. That's normal? I was guessing something in the kiliohms range.

I agree, but I'm afraid at this point that it could have damaged the coil as well. For GM cars I always recommend replacement of the ignition module as a preventative even if it still works.

It's the girlfriend's car which she bought from a sleazy used car dealership with 170k miles on the clock. Who knows when or if it has ever been maintained or tuned up. The inside of the cap looked about as bad as I've ever seen. Surprisingly it ran very well, but it is a Honda.

I'd like to use OEM replacement parts but I *must* get the car running this weekend (she's driving MY new truck to work right now!) so it'll get whatever Autozone has to offer.

Thanks for the link. That's a good site. Wish I had a dwell meter to perform the recommended test. I'm contemplating plugging my oscilloscope into the low side to look for pulses before condemning any $100+ ignition parts that I don't fully understand.

I'll post back what ends up fixing it - might help someone else someday. Thanks for the advice!

-rev

Reply to
The Reverend Natural Light

I misread the manual, for one thing. I think what you are measuring is the resistance of a circuit with a capacitor in it. See the top drawing at

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Jim Yanik can chime in here and see if I have it right now.

What the manual specifies to check is the resistance between (1) the high tension positive terminal (called terminal "A" in the manual, and having a black/yellow wire connecting to it) and (2) the secondary terminal (= the "coil tower" in some manuals = the part of the coil going to the distributor cap and plugs, etc.). It is this resistance that is supposed to be in the kiliohms range.

Towards the bottom of the following site, the procedure is described, with specs:

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Some fellow posted in the last year or so that for something like $200 for parts, he slapped a new Autozone distributor (housing, igniter, coil, the works) into his Honda and it fixed it right up.

It's not a long term fix, IMO, because the OEM parts are superior, from my experience (91 Civic, original owner, myriad distributor problems) and reading here.

Reply to
Elle

"Elle" wrote in news:JJCbh.5220$ snipped-for-privacy@newsread1.news.pas.earthlink.net:

Most any meter should be able to read 200K ohms full scale,up to 2 megohms FS is very common.

My $3 Harbor Freight DMM has a 2 Meg range,my 4.5 digit DMM goes up to 20 Meg.My analog Simpson 270-3 goes up to 2 meg FS.

Reply to
Jim Yanik

"Elle" wrote in news:LEEbh.5256$ snipped-for-privacy@newsread1.news.pas.earthlink.net:

He said he was measuring to -ground-,which only works if the igniter is grounding the coil,which it does not do with the car off.

(grounding the ign.coil charges it up,and ungrounding the coil afterwards generates the spark voltage.That condenser is actually part of the HV current path!)

Actually,on a 20K or 200K meter range,it does not matter which side of the primary he measures to the center post(wht/blu or blk/yel to post),as the primary is so low a resistance,the meter sees it as a short,and only measures the High Tension(HT) side of the coil. That's after measuring the low side of the coil so you know it's not open. I suspect it's rare the low side (primary) of the coil has any problem.

Good info you've given here,Elle. Thx!

Reply to
Jim Yanik

"Jim Yanik" wrote

I was indeed thinking of an old analog meter my dad still keeps around, dating from I bet the 1950s or possibly earlier. (He bought me a digital multimeter a few years ago.) But I haven't used his old analog enough to realize it most likely goes up to at least the high k-ohm range. On the third hand, I reckon it's pretty rare for anyone the least bit handy with cars these days to be using an analog meter these days with regularity.

Thanks for explaining all, Jim Y.

Reply to
Elle

"Jim Yanik" wrote

From the schematic, I see your point and agree. Good lesson. :-)

Reply to
Elle

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