My 91 "faked me out" with a no start- anything to check?

[billschroeder5842]

My '91 gave me a "start" this morning by non starting, then starting, so let me start...

Leaving for work, I turned the key on and hadfull power to the dash however the turn of the key forward and nothing...nothing. I made sure my clutch was fully depressed and again, nothing. My first thought was VATS and I went into the house to get the (new) spare.

A few (less than 5) minutes later I used the new key and *pop* the engine turned and started right up as usual. I let it run for about 10 seconds, turned it off and tried again with the "old" key and *pop* everything turned and the engine started right up. Huh?

I took the '89 to work today as I didn't want to trust the 91 until I did some more checking. (I love my ZR1 but the '89 is very fun and "scooty").

I'll read over the stickys on "the dreaded no start" later tonight, but since I had a few minutes at work, I'd ask if there was a couple of obvious things I needed to check first?

The '91 has been 100% bullet proof in the 18 months and 8K miles I've had her.

Thanks guys!!

[DRM500RUBYZR-1]

Check simple things first:
1- Make sure that if you have the usual logo replacement floor mats that are 3 times the thickness of the originals, that it indeed lets you depress the clutch pedal ALL of the way. Occasionally, the mat may slide forward and up, and while you think you are depressing it fully, you may be missing it by a little.


2- Check your battery connections. I know they LOOK tight, but grab the wrench and make sure that they ARE tight.


3- Battery? How old? On a Battery Tender? These cars are VERY sensitive to battery condition. If you have even mildly reduced voltage, strange things happen. Check it or charge it, then check it.


4- When you turn the key, observe if you have a deflection of the volt meter needle. It should move when you bump the key.
If you see no movement, you may not be getting by the clutch switch, the VATS, or the theft deterrent system.


Rule out the obvious and simple causes FIRST.


Find the no start sticky and march through it!


Let us know of your progress.
Marty

[billschroeder5842]

Originally Posted by DRM500RUBYZR-1

Check simple things first:
1- Make sure that if you have the usual logo replacement floor mats that are 3 times the thickness of the originals, that it indeed lets you depress the clutch pedal ALL of the way. Occasionally, the mat may slide forward and up, and while you think you are depressing it fully, you may be missing it by a little.


Let us know of your progress.
Marty

Well, "duh" on me and thank you.

It just so happens that I put in a new set of embroidered thick mats about two weeks ago. I just got home from work and checked the mat and found that it slid up about 1-2 inches- probably enough to have caused the initial disconnect this morning. I moved the mat back and put in the "old" key and the car started right up.

Hopefully that solves the problem.

Thanks Marty!

[conesare2seconds]

Agree with Marty. Mine sometimes doesn’t want to start. Advice from the Registry is to recondition the starter solenoid contact points. Requires a plenum pull, unfortunately, but I’m planning it for later in the Spring.

[XfireZ51]

Originally Posted by billschroeder5842

My '91 gave me a "start" this morning by non starting, then starting, so let me start...

Leaving for work, I turned the key on and hadfull power to the dash however the turn of the key forward and nothing...nothing. I made sure my clutch was fully depressed and again, nothing. My first thought was VATS and I went into the house to get the (new) spare.

A few (less than 5) minutes later I used the new key and *pop* the engine turned and started right up as usual. I let it run for about 10 seconds, turned it off and tried again with the "old" key and *pop* everything turned and the engine started right up. Huh?

I took the '89 to work today as I didn't want to trust the 91 until I did some more checking. (I love my ZR1 but the '89 is very fun and "scooty").

I'll read over the stickys on "the dreaded no start" later tonight, but since I had a few minutes at work, I'd ask if there was a couple of obvious things I needed to check first?

The '91 has been 100% bullet proof in the 18 months and 8K miles I've had her.

Thanks guys!!

Sometimes, not often but w little warning, I get a ZING when turning the key as if the flywheel was missing a tooth. Wait a few moments and VOILA!

[Paul Workman]

Originally Posted by XfireZ51

Sometimes, not often but w little warning, I get a ZING when turning the key as if the flywheel was missing a tooth. Wait a few moments and VOILA!

Dom,
That "ZING" is a classic symptom of a bendix going south. If that is what it is, it will get worse until it won't "lock" at all.

One other thing: Did you ever replace the armature as part of the Denso rebuild kit? If so, I noticed the thrust pin on the kit I bought was 5-6mm SHORTER than the original. If I had used it, it wouldn't push the bendix out far enough to fully engage the FW ring gear. That being the case, I would not be surprised if there was some potential for buggering up the teeth on the ring gear (among others).

Bill,

The clutch safety switch can start to fail intermittently before completely failing, OR all at once (tho not common to do so).

That frigging "nanny" switch is a SHOW STOPPER! (The LAST thing I want to do is be on a road trip or return to the car after a nice dinner with the wife, and have that damn switch raise its ugly head!!)

So, contrary to what some say, on a 90-92, until you can install a relay (behind the battery - see Cliff's "Solutions" for details), I recommend bypassing that switch. If you have a 93-95 the start circuit includes a relay and the safety switch no longer has to carry the high (solenoid) current load.

New Denso solenoid contacts are under $10. And, the bridge ring can be cleaned up with some emery cloth, and you're good to go - reusing the OE armature.

[billschroeder5842]

**update**

I jumped in the ZR1 to double check the start situation after lunch. I pushed in the clutch and turned the key.... nothing. With the key still forward, I push a little harder on the clutch and the car popped right off.

Clearly I have a "clutch pushing issue." I will have to get in the habit of pushing a little harder.

Here is a question... does the clutch solenoid get progressively worse (more pressure needed as they age as in an alignment issue) or are then pretty binary (works or doesn't)?

Thanks!

[DRM500RUBYZR-1]

Originally Posted by billschroeder5842

**update**

I jumped in the ZR1 to double check the start situation after lunch. I pushed in the clutch and turned the key.... nothing. With the key still forward, I push a little harder on the clutch and the car popped right off.

Clearly I have a "clutch pushing issue." I will have to get in the habit of pushing a little harder.

Here is a question... does the clutch solenoid get progressively worse (more pressure needed as they age as in an alignment issue) or are then pretty binary (works or doesn't)?

Thanks!

Yes.
They progressively worsen and or completely fail.
They are not really adjustable, although you can "rock" them a bit either way while tightening them, and or try to bend the rod slightly.
However once you are down there it is easier to just replace it with a new one.
Corvette America and others have them as a stock item.
First however make sure that your clutch fluid is clean and full.
If black, remove and refill 2-3 times with an extractor or even a turkey baster, then fill to proper level.
Re-evaluate pedal travel once fluid is at correct level, and see if switch now works more often without having to crush the pedal.
If it does not.
Replace the switch.
The switches like to fail catastrophically, when pumping up the pedal 50 times or so after a slave or master cylinder replacement.
Resist the urge to bypass the switch.
Your front or rear bumper will thank you someday for that.
Keep us posted.
Thanks,
Marty

[billschroeder5842]

Thanks Everyone. I checked the clutch fluid and found it to be full and a healthy light yellow color.

I hopped in started twice this morning, both times good (one required a little extra but nothing TOO crazy)

I had a few friends over yesterday; one had a 90 ZR1 and the other had a 96 GS to join my 91 ZR1 and 89. For About two hours I had the coolest driveway in Texas.

With the aid of a few beers we tested, swapped mats measure carpet thickness...etc. In true car guy fashion we turn a 5 minute car project into 90 minutes of over engineering. The end result was to leave well enough alone, keep an eye on the carpet and push slightly harder.

I will however, pick up a clutch safety switch just to have one handy...just in case.

[Z51JEFF]

I’m surprised nobody has mentioned the secondary starter relay modification. I did the second relay mod and haven’t had a problem since.