'90 wouldn't start

[bobbyhi]

Darndest thing just happened. I went out for dinner with the Z and when I came out it wouldn't start. All of the electrical was working just fine and battery was @ 12 volts. When I turned the key there was nothing-nada,zilch. Tried moving the shift lever and clutch petal and still nothing. Put the key in and out a couple of times and still nothing. Was going to call for a flat bed after about 10 minutes of trying. Figured I would try one more time and it started right up. I haven't had any problems since buying it couple of years ago. Any insight as to why it didn't start??? No codes have shown up......

[Ccmano]

Apparent your's is a common problem...this link should cover it...:wink:

http://www.zr1netregistry.com/ZR1_troubleshooting.htm#Start

[RICHARD TILL]

same exact thing happened to me the second time i drove my 90-Z. i was on a date that i really wanted to make an impression. she helped me push the car off. it got so bad that i`d only park on a hill because i found that it would start by letting the clutch out on a roll. a new starter fixed my problem. leaves had stopped up the drain hole.

[tccrab]

Darndest thing just happened. I went out for dinner with the Z and when I came out it wouldn't start. All of the electrical was working just fine and battery was @ 12 volts. When I turned the key there was nothing-nada,zilch. Tried moving the shift lever and clutch petal and still nothing. Put the key in and out a couple of times and still nothing. Was going to call for a flat bed after about 10 minutes of trying. Figured I would try one more time and it started right up. I haven't had any problems since buying it couple of years ago. Any insight as to why it didn't start??? No codes have shown up......

Ahhhaaa....
The Dreaded No Start.
My favorite topic. :mrgreen:

After a short drive, park the car, come back a little later,
Put the key in and..... (drum roll please)............................
Nothing.
Everything else works.
Lights, vacuum pump, radio, interior lights.
Yup, all work fine.
It's not the VATS (you check that first, 'cause it's a known failure)
But not even a "click" from the starter solenoid.
Nada.
Zilch.
Oh, the stress.
Oh, the agony.
Oh, the anger........
You try different keys (that VATS thing again)... :pray
Nada.
Nope.
Only to have the F :censored:ing thing start after 10 or 15 minutes.
In some cases, the car is towed to the local shop where the mechanic gets in and fires it right up. :redface:
In other cases, just as the tow truck shows up, the driver tries one more time and it fires right up, but you've still gotta pay the towing fee, even though he never hooks up...:mad:
The next day everything checks out fine.
Relays, fuses, clutch safety switch, wiring, everything fine.
Starts right up.
Smirks at you, dares you to trust it.
Double Dog dares you.
Go ahead, get in, it says seductively.
Take me for a drive, big boy.
You know you want to...
It had to be something that you did, couldn't be the car, right?
Just don't turn it off until the car is back in it's garage.
Riiighhhhtttt...


Too much resistance in the starter wiring. Solenoid won't even budge if it's not getting just the right amount of current. GM realized they had a problem and changed the wiring in the '93 model year.
My answer is to bypass all the crap and fire the solenoid directly off of the battery. See the following link:
http://www.zr1.net/forum/showthread.php?t=1849

Drop me a note if you need more details, info, instructions, etc.

Good luck!

TomC
'90ZR1 #792

[bobbyhi]

Tom - thanks for your help. I went back and read your post in the forum about what you did with a direct relay to the solenoid. I am going to try the same application you used. Where did you go thru the firewall? I haven't looked for a spot yet but if you've been there and done that I could probably same some time. Sure hope you're around when I do this project. Don't think I've got the moxy for any major unforseen electric problems.............

[tccrab]

There's not a lot of room under the drivers side to access the wiring so I went the easy route by accessing the start signal from the passenger side.
There's a secondary fuse panel under the hush panel on the passenger side, and it's got a fuse labeled "CRANK". This is the 12V from the start signal on the ignition switch. It's a yellow #12 wire. I spliced in there and routed my wire through the door wiring grommet to the side panel. From there it is routed up along the top of the firewall, zip tied to the windshield washer tubing. I used black wire and black zip ties so that it is very difficult to see.
I positioned the relay just under the ECM and accessed the purple wire inside the wiring loom. I cut and capped the purple wire from the dash side, and spliced in a wire from the relay to the starter side of the purple wire.
I spliced into the accessory wires on the battery cables for the 12V and ground.
Everything is hidden out of sight and can only be seen if you know what you are looking for.

The starter will crank when the key is in the "Start" position.
Every time.
Even if you forget to push in the clutch.:rolleyes:
Even if the VATS is triggered, although if it's triggered there won't be any spark or fuel so it doesn't really defeat the VAT's purpose and intent. Even though it'll crank, it won't start. :wink:
I did catch some crap from other forum members about the clutch safety switch, but you've got to be really stupid to turn the key withouth having it in neutral or the clutch in. *sheesh* :icon_scra

I've since learned that replacing the starter & solenoid has fixed some people's "No Start" issues, but in my case since my Z only has 10,800 miles, I have a hard time believing that the starter is bad.
I bought my car from a collector buddy of mine. It's first 15 years were spent in a climate controlled warehouse lovingly cared for by a Chevy master tech. It has never seen the rain, nor has anybody EVER hosed the engine down.
Bad starter? Bah.
Bad wiring from GM?
Much more likely!

TomC
'90ZR1 #792

[bobbyhi]

I've decided to replace the battery first. I don't think that it is putting out enough volts ( 10.4v). The nearest I can tell, the battery is over 4 years old and getting weak. I remember a discussion regarding which battery to use in the Z's on the forum a few months back. If I remember it was pretty much a "cat from every county".

The bad thing is now everytime I use the Z it will be in the back of mind "is this thing going to start after I've stopped?". If the "no start" happens again I will use Tom's method with a relay.

How do I find the old forum regarding the batteries????

[guinnessdood]

I've decided to replace the battery first. I don't think that it is putting out enough volts ( 10.4v). The nearest I can tell, the battery is over 4 years old and getting weak. I remember a discussion regarding which battery to use in the Z's on the forum a few months back. If I remember it was pretty much a "cat from every county".

The bad thing is now everytime I use the Z it will be in the back of mind "is this thing going to start after I've stopped?". If the "no start" happens again I will use Tom's method with a relay.

How do I find the old forum regarding the batteries????
http://www.zr1netregistry.com/forum/showthread.php?t=1518&highlight=battery

If you have 10.4 it definitely WILL NOT start. It won't even try. A new battery probably solved your problem...in the future if you have the no start but your voltage is OK...you may want to do the mod.

[bobbyhi]

Uly,

I did put in a new battery and so far no problems. I hope that was the cure. Thanks for the reply............

[Kevin]

did you bypass the clutch switch?

[bobbyhi]

No, I did not do the bypass thing (yet). Hoping that it was the battery only. If not, you guys will be the 2nd to know!!! Since I have replaced the battery there has not been any problems. According to some of the previous posts regarding this subject, the problem is not constant meaning that it might not always happen. So far so good but it has only been a week. We have our big Corvette show next weekend. Sure would be embarrassing if it wouldn't start during the judging!!! :rolleyes: :rolleyes:

[Kevin]

even if it's not your clutch switch you should still jumper it out
Here's how:
Pull driver’s side hush panel.
Locate striped purple wire that goes to clutch switch.
Look at switch and note the color of wire coming back up.(Yellow??)
If you found them—the jumper will go from the Yellow to the purple stripe. You be able to jumper them right there without messing with that ##*!!$ clutch switch.
I used a 3 in #12 wire with terminals (from Radio Shack number 64-3133) on the end and unplugged the wires going to switch and plugged in the jumper wire.
Use a 12 ga wire at least as it does carry a heavy current load which is why the switch fails, it gets hot and the resistance across the points stops current flow.

[bobbyhi]

Thnaks for the tip Kevin. I will do that after the show this weekend!!!

[rkreigh]

correct me if I'm wrong, but the clutch circuit was changed in the later zr1s to fix this problem. having said that, I had the "no start" the other day too. maybe it was a coincidence (this happened on another 95 I had, but only once) I pulled the ecm fuse and put it back in. fired right up.

now, I don't think this was the security system, but this doesn't make any sense either.

the first time it happened to me I was driving a 95 home from florida.

man was I embarrassed. but yes, this is where I first tried the ecm fuse pull trick out of desparation. it worked that time too. go figure.

[Zr1 Destroyer]

:icon_scra The only wires I could locate for this clutch pedal switch was a grey/blk and a blk wire....am I looking at the right switch???:icon_scra I removed the drivers side panel and followed the clutch pedal up to a this switch...is there another switch above this one??????:o


Ry

[Kevin]

Ry,
It's been a few years since I did this and the colors maybe off. I don't have my manual in front of me but let me see if I can dig up an old email where I was helping someone else with this.

Tyler posted this:
Pull the drivers side hush panel. You should see a connector wire a
large purple wire and a black wire. This plugs into a connector with 2
black wire. Disconnect and jumper the purple wire to the black wire in
that connector and you should be good to go.

[Zr1 Destroyer]

Cool...mine is a 1991, if that helps at all?

[Tom]

I believe there are two switches on the clutch pedal. One for the starting and one for the cruise control.

[Jeffvette]

I believe there are two switches on the clutch pedal. One for the starting and one for the cruise control.

The clutch switch is mounted on the left hand side of the footwell, and is a swing arm that makes contact with the other side of the switch. You must have the clutch pedal all the way down, otherwise you are arcing the circuit and destroying it. GM revised the design in the later cars.

The cruise control switch is at the top of the pedal, and senses any slight movement in the pedal and disengages the cruise.

[Zr1 Destroyer]

I believe there are two switches on the clutch pedal. One for the starting and one for the cruise control.Mmmm...I'll have to take a further look around to see if I can find what you guys are talking about.


Thanks guys...checking it tonight!:cheers:

Ry:hello:

[rjb48]

What is the minimum voltage required? My voltage is measuring 11.6 at the the ALDL using a scan tool. Car will not crank with a jump.

[tccrab]

Something weird going on here...
Apparently RJB48 just posted something to this thread because I just received an email notice, but his post does not seem to be here...
:icon_scra:icon_scra
The INTERESTING thing is that his post shows up in the Topic Review which shows up just below the "Reply To Thread" box when I'm typing up this reply.

OK, now it decides to show up.:redface:
Oops.
My Bad...


Just because the ALDL reports 11.6 does not mean that is what the starter solenoid is seeing. Your problem could still be under the dash.
Have you jumpered out the Clutch safety switch?
Checked the Starter Relay?
What year is your Z?
(Fill out your user profile)
Has the engine ever been washed with water?
GM knew that the early years (90-92) were having occasional problems with the starter so in '93 they redesigned the start circuit.

Not surprising that jumping didn't do anything. If it's the "DNS" then jumping won't help. Same story if it's a bad starter/solenoid.
The trick here is to diagnose the fault without having to pull the plenum.

[DaveK]

OK, now it decides to show up.:redface:
Oops.
My Bad...


No, I saw exactly the same thing too - wierd...