86 L98 Won't Start
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
86 L98 Won't Start
This problem started out as an intermittent issue where occasionally the engine would not kick over usually after it was warm. I have a VATS bypass system installed in bypass mode.
Generally a squirt of starting fluid would get it to run and if I immediatley shut it off it would start right up again. If I let it sit it amay or may not start again.
It became more frequent. Engine cranks but no starting. I replaced the battery, plugs & wires. No help although I believe the old battery was a little tired.
Last weekend it was in the no start mode. Even starting fluid wouldn't make it come to life. I checked the fuel pressure and it was a solid 42PSI and holding.
I thien noticed that the ground wire that connected to the frame was corroded and covered with corrosion from the battery leaking before. I squirted it off with a hose ... tried to start it and it jumped to life.
I was excited that I might have solved it and removed my battery and cleaned the terminal and ground the frame to bare metal ... reinstalled it all and now it still is in the no starting mode.
Now I'm scratching my head again ... Do I need to replace the ground wire?
Thanks In advance
Robert Harker
PS: My codes are all 12's
Generally a squirt of starting fluid would get it to run and if I immediatley shut it off it would start right up again. If I let it sit it amay or may not start again.
It became more frequent. Engine cranks but no starting. I replaced the battery, plugs & wires. No help although I believe the old battery was a little tired.
Last weekend it was in the no start mode. Even starting fluid wouldn't make it come to life. I checked the fuel pressure and it was a solid 42PSI and holding.
I thien noticed that the ground wire that connected to the frame was corroded and covered with corrosion from the battery leaking before. I squirted it off with a hose ... tried to start it and it jumped to life.
I was excited that I might have solved it and removed my battery and cleaned the terminal and ground the frame to bare metal ... reinstalled it all and now it still is in the no starting mode.
Now I'm scratching my head again ... Do I need to replace the ground wire?
Thanks In advance
Robert Harker
PS: My codes are all 12's
Last edited by 3D-Aircrew; Mar 5, 2008 at 09:43 AM.
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
wiring
I understand that there is a ground plug connection connected to the frame. I intend to find and clean that as well this weekend. The hot wires all looked OK.
Maybe that's what got wet and made a better connection when I started it last weekend.
Thanks
Maybe that's what got wet and made a better connection when I started it last weekend.
Thanks
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
Low voltage on the display
I'm on a new well charged bosche battery however the display on the console only reads 12V with the IGN on and drops to 10 when cranking.
Where does that voltmeter connect to the battery?
Where does that voltmeter connect to the battery?
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
What does it read when the car is running?
GM Voltmeters are pretty inaccurate, you need to verify it with your own voltmeter.
GM Voltmeters are pretty inaccurate, you need to verify it with your own voltmeter.
Melting Slicks
Joined: Feb 2008
Posts: 3,286
Likes: 6
From: Palm Beach
Melting Slicks
Joined: May 2007
Posts: 2,382
Likes: 2
From: Kathleen FL
I would check the TPS voltage. It should be between .5 to .7 volts. If over .7 volts the ECM might be in clear food mode.
I also check to see if you have spark. I would do this by disconnecting a plug wire from a spark plug and seeing if it will spark to the ground. Or hold it and check if you get a jolt. Sometimes that can be fun when you are sleepy in the morning. It sure does wake you up!
If there is no spark, I would check for a loose connection to the coil. If you have spark, I'd also check to see if there are no shorts to ground on your fuel injectors.
If you have spark, I would check to see if your spark timing is correct.
Good luck...
I also check to see if you have spark. I would do this by disconnecting a plug wire from a spark plug and seeing if it will spark to the ground. Or hold it and check if you get a jolt. Sometimes that can be fun when you are sleepy in the morning. It sure does wake you up!
If there is no spark, I would check for a loose connection to the coil. If you have spark, I'd also check to see if there are no shorts to ground on your fuel injectors.
If you have spark, I would check to see if your spark timing is correct.
Good luck...
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Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
agent 86 photo
Agent 86;
I'm not sure where the picture is located. Is that the LH side Aft of the block?
It seems to me there should be a heavier connection to the battery to the frame.
I have the wire braid connected under the ground wire from the battery (-) cable which is only #12 AWG. Would there be another ground point by the other end of the (-) battery cable?
My buddy gave me a timing light which should make tell me if I'm getting spark signals.
Thanks All
I'm not sure where the picture is located. Is that the LH side Aft of the block?
It seems to me there should be a heavier connection to the battery to the frame.I have the wire braid connected under the ground wire from the battery (-) cable which is only #12 AWG. Would there be another ground point by the other end of the (-) battery cable?
My buddy gave me a timing light which should make tell me if I'm getting spark signals.
Thanks All
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
Yes, right above the oil filter. My ground cable goes from bat to the location in pic. The braided strap goes from location in pic to firewall.
If you have spark, get a noid light and see if injectors are being pulsed duiring cranking.
If you have spark, get a noid light and see if injectors are being pulsed duiring cranking.
Former Vendor
Joined: Nov 2006
Posts: 2,482
Likes: 3
From: Carmichael ca
You could measure the resistance between the battery neg and the engine block with an ohm meter, or get jumper cables, connect one neg to battery neg and the other neg to the engine. If it starts up you have a bad ground connection.
Paul
Paul
Instructor
Joined: Dec 2006
Posts: 195
Likes: 0
From: Savannah Georgia
The VATS bypass system you have installed, is that by chance the one with the 3 position switch? I had one of those on my 90' for all of maybe 2 weeks before finding out it was more of a problem than just the VATS alone. Started out giving me similar issues, making me think the bypass had nothing to do with it, until it left me stranded. Once I yanked the bypass switch out I had no more problems, but I did have fresh ground connections everywhere
I just manually lock the doors now unless I'm leaving the car somewhere sketchy, because manually locking the doors won't engage the VATS system.
Anyway, just another possibility, good luck with your problem
I just manually lock the doors now unless I'm leaving the car somewhere sketchy, because manually locking the doors won't engage the VATS system.
Anyway, just another possibility, good luck with your problem
!
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
VATS doesn't care how you lock your door. The theft deterent module does, though.(horn alarm). 2 different systems (86 and up)
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
Starting Like crazy now...Go figure
Didn't do anything now it's in the running good mode...makes troubleshooting a pain.
It's still broke though but I'm hesitant to disturb it.
It's still broke though but I'm hesitant to disturb it.
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
I might have been flooding it
I found out that I'm not supposed to give any gas when starting a FI corvette engine. I used to do this which may have been flooding it at times.
I'll be dipped in snot if that's all it was!
I hope I'm right.
I'll be dipped in snot if that's all it was!
I hope I'm right.
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
Will make starting a little harder
