90Z won't start - ZR-1 Net Registry Forums

lfalzarano · 08-08-2022

The new battery tested 700 CCA. The car has been sitting for a month on a charger. With the clutch to the floor, I turn the key and the dash lights up, and then turn the key to start and the portion of the dash ahead of the steering wheel dims a little. The starter does not crank.

I'm sitting at the bottom of my driveway so there is no way to push start it. It is reminiscent of the usual DNS threads after driving and parking. But it hasn't been driven nor was the engine hot.

Suggestions to where to start in the FSM or posts?

Young1 · 08-08-2022

Two questions for you
When you turn key to crank does the voltage lower on the voltmeter?
How many miles on the car?

Dynomite · 08-09-2022

The solenoid and the solenoid contacts need cleaning.......

Often if you keep trying with the key start a "good enough" solenoid contact enough for starter current can be made.....you may then be OK for a while or the next day have a repeat until you refurbish the solenoid.

This does happen more often with a starter/solenoid that has not been used for a while.

Push the car out of your driveway and have a couple of guys then push the car forward and you pop the clutch in second gear with key on.

lfalzarano · 08-09-2022

Quote:

Originally Posted by Young1

Two questions for you

When you turn key to crank does the voltage lower on the voltmeter?

How many miles on the car?

No the voltmeter never moved. As to your second question, the mileage is 86K.

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lfalzarano · 08-09-2022

Quote:

Originally Posted by Dynomite

The solenoid and the solenoid contacts need cleaning.......

Often if you keep trying with the key start a "good enough" solenoid contact enough for starter current can be made.....you may then be OK for a while or the next day have a repeat until you refurbish the solenoid.

This does happen more often with a starter/solenoid that has not been used for a while.

Push the car out of your driveway and have a couple of guys then push the car forward and you pop the clutch in second gear with key on.

It only sat for a month. But I need to get some younger friend to assist in a push start. My problem is the car is sitting at the bottom of the driveway hill. There is about 35 feet of level driveway. We might be able to have it kick over before I?m back in the garage[emoji1317]

Thanks for the suggestion. I will give it a go.

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KPW · 08-09-2022

Lots of detail to be found here:

http://www.zr1specialist.com/HAT%20W...20Problems.pdf

If the voltmeter isn't dropping, it might be worth shorting the clutch safety switch (have a look at the last paragraph in the PDF above).

For what it's worth, I fought the "no start" intermittently for a while, including shining up the solenoid contacts. Finally bit the bullet and did the DNS Relay Mod - completely worth it for the peace of mind.
http://www.zr1.net/forum/showthread.php?p=88156

lfalzarano · 08-09-2022

I went through Marc?s guidance and it all points to under the dash as the source.

I?ve tried other suggestions except the push starting it. I called AAA to flatbed it to my dealer in Cary, NC. They replaced the clutch pedal position switch less than 6 months ago. It was a MidAmerican Motorworks part, but I don?t know who made it.

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tiegsd · 08-09-2022

Just had no start issue with my 90, it was the clutch switch. Easy enough to test and bypass to get the car to start. Made up a jumper for the connector under the driver's side hush panel till I can get a replacement. If not that, things get a little harder, starter contacts are known issue per previous posts. VATS is another potential trouble spot if yours hasn't been bypassed (mine is).

Matt B · 08-10-2022

I can only recommend the relay mod. A power relay and proper wires will deliver way more power to the starter.
I had a DNS right on the first day she ran in my yard. Did the mod and it never came back. AND this solution maintains the clutch safety switch which is a useful feature.

Young1 · 08-10-2022

I agree with tiegsd on the clutch switch. Easy to bipass with two spade connectors. Check that first. Then second I agree with dynamite. plenum pull to shine up the copper contacts. This will happen every 35 to 40 K miles. So far I have cleaned contacts several times but never replaced a clutch switch.

08-08-2022	#1
lfalzarano Join Date: Feb 2011 Location: Clayton, North Carolina Posts: 1,133	90Z won't start The new battery tested 700 CCA. The car has been sitting for a month on a charger. With the clutch to the floor, I turn the key and the dash lights up, and then turn the key to start and the portion of the dash ahead of the steering wheel dims a little. The starter does not crank. I'm sitting at the bottom of my driveway so there is no way to push start it. It is reminiscent of the usual DNS threads after driving and parking. But it hasn't been driven nor was the engine hot. Suggestions to where to start in the FSM or posts? __________________ Lou[COLOR="Red"][B][SIZE="4"][/SIZE][/B][/COLOR]

08-08-2022	#2
Young1 Join Date: Sep 2016 Location: Ocala, FL Posts: 895	Re: 90Z won't start Two questions for you When you turn key to crank does the voltage lower on the voltmeter? How many miles on the car? __________________ Steve Young 1991 ZR-1 Quasar Blue Metallic/Black #729 Second Owner 1991 ZR-1 Dark Red Metallic/Black #2040 SOLD 1990 ZR-1 Dark Red Metallic/Saddle #1670 SOLD Double your happiness.....complain half as much.

08-09-2022	#3
Dynomite Join Date: Aug 2009 Location: South Dakota/California Posts: 3,797	Re: 90Z won't start The solenoid and the solenoid contacts need cleaning....... Often if you keep trying with the key start a "good enough" solenoid contact enough for starter current can be made.....you may then be OK for a while or the next day have a repeat until you refurbish the solenoid. This does happen more often with a starter/solenoid that has not been used for a while. Push the car out of your driveway and have a couple of guys then push the car forward and you pop the clutch in second gear with key on. __________________ Left Clickable links -Solutions- LT5 Modifications/Rebuild Tricks Low Mileage ZR-1 Restoration 1990 Corvette (L98) Modifications LT5 Eliminated Systems LT5 Added Systems LT5/ZR-1 Fluids 1995 LT5 SPECIFIC TOP END REBUILD TRICKS Last edited by Dynomite; 08-09-2022 at 12:56 AM.

08-09-2022	#6
KPW Join Date: Jul 2015 Location: Ypsilanti, MI Posts: 116	Re: 90Z won't start Lots of detail to be found here: http://www.zr1specialist.com/HAT%20W...20Problems.pdf If the voltmeter isn't dropping, it might be worth shorting the clutch safety switch (have a look at the last paragraph in the PDF above). For what it's worth, I fought the "no start" intermittently for a while, including shining up the solenoid contacts. Finally bit the bullet and did the DNS Relay Mod - completely worth it for the peace of mind. http://www.zr1.net/forum/showthread.php?p=88156 __________________ 1991 ZR-1 #1438 Black/Black & Red

08-09-2022	#7
lfalzarano Join Date: Feb 2011 Location: Clayton, North Carolina Posts: 1,133	Re: 90Z won't start I went through Marc?s guidance and it all points to under the dash as the source. I?ve tried other suggestions except the push starting it. I called AAA to flatbed it to my dealer in Cary, NC. They replaced the clutch pedal position switch less than 6 months ago. It was a MidAmerican Motorworks part, but I don?t know who made it. Sent from my iPhone using ZR-1 Net Registry __________________ Lou[COLOR="Red"][B][SIZE="4"][/SIZE][/B][/COLOR]

08-09-2022	#8
tiegsd Join Date: Jul 2017 Location: West Chester, PA Posts: 378	Re: 90Z won't start Just had no start issue with my 90, it was the clutch switch. Easy enough to test and bypass to get the car to start. Made up a jumper for the connector under the driver's side hush panel till I can get a replacement. If not that, things get a little harder, starter contacts are known issue per previous posts. VATS is another potential trouble spot if yours hasn't been bypassed (mine is). __________________ 1990 Black/Black ZR-1 #1155 1993 White/Red coupe (Regrettably sold)

08-10-2022	#9
Matt B Join Date: Jan 2021 Location: Beautiful Bavaria Posts: 523	Re: 90Z won't start I can only recommend the relay mod. A power relay and proper wires will deliver way more power to the starter. I had a DNS right on the first day she ran in my yard. Did the mod and it never came back. AND this solution maintains the clutch safety switch which is a useful feature. __________________ ZR-1 #638/1991

08-10-2022	#10
Young1 Join Date: Sep 2016 Location: Ocala, FL Posts: 895	Re: 90Z won't start I agree with tiegsd on the clutch switch. Easy to bipass with two spade connectors. Check that first. Then second I agree with dynamite. plenum pull to shine up the copper contacts. This will happen every 35 to 40 K miles. So far I have cleaned contacts several times but never replaced a clutch switch. __________________ Steve Young 1991 ZR-1 Quasar Blue Metallic/Black #729 Second Owner 1991 ZR-1 Dark Red Metallic/Black #2040 SOLD 1990 ZR-1 Dark Red Metallic/Saddle #1670 SOLD Double your happiness.....complain half as much.