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1989 Sedan de Ville won't start


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Hello All,

         I've now officially hit the first major problem with my car in the 3.25 years that I've owned it.  She won't start.

         Up until yesterday things were working pretty much as they always had, turn the key and within a couple of revolutions of the starter she fired right up.  However, there has been one change recently, which while intermittent, did recur off and on and that is that she'd run for a few seconds and stop.  This was maybe one out of every 50 or so starting cycles, so I wrote it off, but now I'm thinking that this may have been a warning sign.

         Based on what I know about fuel injection, which isn't a ton, I'm wondering if the accumulator may have bitten the dust.

         The battery in the car is excellent and the starter cranks the motor at very high speed, so I'm sure that isn't the problem.

         Any assistance in diagnosing or repairing this issue would be most appreciated.  This one's entirely new territory for me, and the "sudden death" aspect of it after having been functioning virtually perfectly and normally up to the time of being parked last night leaves me more than a little perplexed at what range of issues might cause this behavior.

Brian

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There are several things to check.

2) It was not uncommon for the fuel gauge to be inaccurate. If the fuel gauge indicates 1/2 to 1/4 put about 5 gals of fuel in it and try starting it. The baffles would also break loose in the fuel tank and cause the fuel gauge float to stick.

3) With the inlet removed from the throttle body, have someone crank the engine while you spray a shot of brake clean or WD-40 into the throttle body. If it starts on the brake clean or WD, the fuel pump would be at the top of the list to check. If it runs, It will also eliminate PCM and ignition problems.

1) Since I know you have a FSM, follow the diagnostic tree for cranks will not start. Yea I know its out of sequence but do the EASY stuff first. But nothing wrong with starting here.

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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Are there any trouble codes stored in the diagnostics?  A bad pickup coil on the distributor or rotted/corroded distributor wiring could also be the issue but the trouble codes would help.

Have you checked for spark?

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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Thanks to both OldCadTech and KHE for their responses.

First, I have not checked for anything.  As soon as this occurred yesterday I punted to my other car and was busy for most of the day.

I fully intend to have a look at the Service Manual that I have but, as is so often the case and that has been shown in both these responses, the knowledge of the cohort, many with years of experience, will give certain "out of sequence" checks that can prevent one from having to go through the full service manual sequence.

As an owner of two British cars I long ago learned that what the factory service manual specifies and what is most effective can be two very separate things.  That's not always, or even frequently, the case but there are enough exceptions to "the manual knows what you should do" that I feel that asking first is a good idea.  My guess is that I won't get working on this in earnest until Monday at this point.

I have WD40, brake cleaner, and starting fluid spray all in my garage.  I'd be more inclined to use the last in that list than the former two for OldCadTech's check which, in one fell swoop, answers the spark question, too.  I am positive that the fuel level is almost full, as I went to the gas station only a day or two ago and have not driven enough to have even consumed three gallons since then.

Should anyone have any other thoughts please toss 'em out!   I always like to knock off the easy checks first.

Brian

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Use the WD or brake clean first, starting fluid only as a last resort. Starting fluid can cause problems.

Hmmm, any possibility you have bad fuel? That's about the time the problem started. Is that correct? Talk to the gas station and ask if they have had any other people complain.

If the engine runs on the WD or brake clean, pull the fuel filter and see if it is restricted.

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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OldCadTech,

         I guess it depends on how you define "about the time the problem started," but by my definition the answer is "no."

         The very occasional stall after starting has been going on for perhaps a couple of months now, but it was so very occasional that I wrote it off.   I had driven the car enough after gassing up this time over the course of a couple of days and everything seemed to be working normally until I went out to start the car yesterday.

          I would value hearing your input on starting fluid.  I have never had any issue with it, have very seldom had to use it, and always used it exactly according to directions.  I have heard of incidents where people have "blown things up" but in every case, when pushed, it turns out they were not using it according to directions and had sprayed enough of the stuff around to make what was, in fact, a small bomb.   Ether is, after all, very volatile - which is kinda the idea - but you've got to use as directed.

 

Brian

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Starting fluid is mostly ether, heptane and propane. Brake and carb cleaners are usually a mix of toulene, methanol, acetone and MEK. Starting fluid is much more volatile but it will vaporize better in colder weather. 

My opinion is starting fluids can pre-ignite easily and have a tendency to "pool" easily. WD and brake cleaners, carb cleaners are slower burning. I personally don't like that heavy "knock" sound when using starting fluids.

But you know what they say about opinions.....

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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OldCadTech,

            Thanks much.

            For those who've asked about DTCs there are none.  When I do the standard "hold down the OFF and WARMER buttons on my climate control" [I have the digital dash] the one and only thing that shows up in the Fuel Data Center display, and immediately, is .7.0, which means no codes are stored or else they would have come before that "no more codes" indicator.

Brian

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Well, in the "fuel or spark" contest it appears that spark's what's missing.

I just had my partner crank the car after I lifted the cover off of the intake and gave a shot of carb cleaner as fuel.  Not only did that not work but you could clearly see that the injector on each side was giving a fine spray of fuel about once per second, alternating, as the car cranked (and, of course, you can smell it, too).

 

Brian

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The 15A ignition fuse in the Relay Center behind the glove compartment is fine.

Brian

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My GM manuals don't go back that far..

Both injectors need to be pulsing...I think the ECM needs the ignition module to pulse the injectors.....so the pick up coil and IC module sound ok. Have you tried replacing the coil on top of the the distributor cap?

Or maybe bad rotor or cap.

 

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I have had a lot of ignition modules go bad. The button on the coils burn AND the coils are also prone to failure.

The FSM will guide you through the ohm checks. The FSM will be worth its weight in gold.

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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Logan,

          I'm hoping this will end up being just the coil.

 

OldCadTech,

          Yep, I intend to start working my way through the diagnostic steps on the page for "non-start," though I may jump in at the middle if the beginning is about checking whether the fuel injectors are injecting since that's been confirmed already.

           At least I now think I will probably be able to repair this here at home.  This car is my daily driver and has been completely reliable until this incident, and I fully expect it will be again after the repair.  She only has 117K on her so I should still have years of service left on her and I really like the car.  This is an "interesting era" in that it has OBD but not that can be read like the later OBD cars can.  It also clearly doesn't monitor as many systems, either.

 

Brian

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Latest report.

First, I'm presuming what the Service Information Manual describes as an "ST-125" (which clearly refers to a spark plug tester) that you're supposed to use to check for spark when cranking is just one of the good, old fashioned testers with a small light that strobes as spark is delivered to each plug.  They tell you to test for spark at two plugs as the first steps.  I decided before I started this to test on my 1996 Buick so that I would know what "normal" looks like when spark is being delivered during cranking.

Well, I have spark, but very weak spark indeed, when cranking.  I am coming to believe more and more that it's the coil but will continue through the diagnostic steps to confirm.

Brian

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Bri the Tech Guy   http://britechguy.com
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Next update.

Thinking that this was likely the coil, I've acquired another to have on hand.

When I removed the existing coil (which may be the OEM one for all I know) the small tinned copper spring with brass washer on the lower end the makes the contact between the coil and the distributor was very badly oxidized and blackish on the bottom side.  The button on the bottom of the coil itself was thoroughly rusted.  I cleaned all this stuff up first but no change.

So, I thought, it's time to pull the coil.  Well, lo and behold, the slide connector that serves as the +12V from the battery was covered in nasty crud, almost like tar, as is the female bit into which it slides.  It's almost as though someone spilled something in there at one point and it's spent years coagulating.  So, at this point I'm trying to get the female slide connector cleaned out by dissolving this crap with Goo Gone, which worked very well in cleaning off the male terminal on the original coil.

I think I'll end up putting in the replacement coil anyway as the next step after that connector is cleaned out to my satisfaction.  I only wish I could think of something that could be rat-tailed into there to give things a good wipe, but the thing is so small that's not practical so I've been doing cyclic "fill, wait, dissolve, dump, repeat" to get as much of this crud out as I can. 

Brian

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The ST-125 is a spark tester for HEI ignitions. Not really a spark plug tester.

If the spark can't jump the gap...from the center to the outer edge...it's too weak. 

You should be able to easily hear the spark snapping from the drivers seat while using one for testing. 

hei.JPG

 

hei3.jpg

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Some photos from what I've done so far.  I have not installed the new coil since I wanted to check on something before I did.   When I cleaned off the spring that goes between the coil and the contact in the distributor I may have stretched it slightly.  I doubt this should make any difference since I imagine the tinned copper end is supposed to make contact with the metal pad on the bottom of the coil when the coil is placed on top of it.  I imagine this thing is the functional replacement for the lead that came out of the top of old-fashioned coils and was connected to the center of the distributor cap and where that lead wire looks like it's made of the same wire used for the spark plug wires.  If not please tell me what configuration that spring is supposed to be in.

The photos are annotated.  You will see on the +12V lead of the old coil what was still coming out of that slide connector during the cleaning process.  The original crud coating was much worse.  It was quite tar like but there is no hint of burning of the plastic on the connector or arcing on the metal, so I am presuming that some time in the distant past something got spilled into this connector that was not known to have happened or was blissfully ignored.  It's obvious that this was not a recent development.  Since then I've done at least six or seven cleaning cycles and you can see bare metal inside the slide connector in the photographs now.  Unfortunately I failed to take any pre-cleaning photographs of that spring, particularly the brass base, which was more black than brass.

Since I'm out of space to upload here, see the photos on this shared Google Photos album.

P.S. to Logan:  Thanks much for the ST-125 info.  Just based on the weak strobing in my spark plug tester when compared to what I saw on my Buick I'd have to presume the spark is very weak.  Depending on what comes back in comments based on the photos I will probably install the replacement coil next and see if she fires up.

 

Brian

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Bri the Tech Guy   http://britechguy.com
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The button is gone! Burnt off or in the distributor someplace.

Ohm test the coil, replace the button and you should be ready to drive.

heibutton.jpeg

After looking at the coil again replace it regardless if it is good or not. There should have been a rubber washer too.

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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There Must have been some serious arcing going on inside the cap. Replace the cap, rotor & coil.

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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What is that spring part with the button called?

This at least explains what I saw with regard to the black crap on the base of the brass bit.  I've already got a new coil and will definitely pop off the cap and have a look around to see what's what.  The rotor and cap are easy enough to replace, too, but I don't know if that little spring bit is included as part of that package or not.

Brian

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Bri the Tech Guy   http://britechguy.com
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It's a wonder sometimes how cars can run..

How long have you owned the car? That sure doesn't look like a 25 year old coil. 

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I've owned the car since January 2014 and it's run like a top until it stopped doing so a few days back.  It is more than a bit of a wonder how cars can run sometimes.  I have to believe that something "catastrophic" happened as I doubt we've been tooling along in the current state for 3 years and 4 months now.

The coil I bought didn't come with the rotor bushing and there is absolutely no evidence of heat sink compound on the coil that was in the car and nothing in the installation instructions for the replacement that makes any mention of same.

Time to get the distributor cap and rotor.

Brian

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Bri the Tech Guy   http://britechguy.com
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For those curious I've added photographs of what was uncovered when the distributor cap and rotor were removed.

It's abundantly clear where that button ended up.

Two photos of the fuel injectors at the throttle body, too.

Brian

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Bri the Tech Guy   http://britechguy.com
britechguy@gmail.com   (540) 324-5032
"If it's got you screaming, I'll help you stop!!"
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