1995 LT1 Hard starting and Stalling
Thread Starter
Pro
Joined: Sep 2000
Posts: 535
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From: California
1995 LT1 Hard starting and Stalling
My Corvette Brethren,
I'm hoping you can help me with a problem. My '95 LT1 with 65K miles was running fine when I drove it everyday for the past 2 years, but now I take the train to work, and only drive the car to work once every 3 weeks or so.
I'm now experiencing a problem where the car takes 2-3 tries to start. In addition, I drove the car to work today, and drove through a long (approx 4 inch deep) puddle of water at about 25 mph, and the car stalled. I coasted to a stop and was able to get the car restarted after about 4 tries.
Does this sound like an optispark issue? I replaced the waterpump at approximately 55K miles, but left the original opti in place because the car was running fine at the time.
BTW - I've driven through big puddles before in my '92 LT1 and never had this problem before. Is it possible for the later vented-opti cars to have problems with water splashing into the opti housing or vent hoses?
I replaced the battery about 3 weeks ago too - do you think that may have something to do with this issue?
Thanks in advance for your help!
USA1LT1
I'm hoping you can help me with a problem. My '95 LT1 with 65K miles was running fine when I drove it everyday for the past 2 years, but now I take the train to work, and only drive the car to work once every 3 weeks or so.
I'm now experiencing a problem where the car takes 2-3 tries to start. In addition, I drove the car to work today, and drove through a long (approx 4 inch deep) puddle of water at about 25 mph, and the car stalled. I coasted to a stop and was able to get the car restarted after about 4 tries.
Does this sound like an optispark issue? I replaced the waterpump at approximately 55K miles, but left the original opti in place because the car was running fine at the time.
BTW - I've driven through big puddles before in my '92 LT1 and never had this problem before. Is it possible for the later vented-opti cars to have problems with water splashing into the opti housing or vent hoses?
I replaced the battery about 3 weeks ago too - do you think that may have something to do with this issue?
Thanks in advance for your help!
USA1LT1
Thread Starter
Pro
Joined: Sep 2000
Posts: 535
Likes: 19
From: California
The fuel filter? I'm not sure - perhaps it's the original one. That might account for the rough starting, but what about the water splashing..?
Last edited by USA1LT1; Feb 18, 2009 at 12:20 AM.
Le Mans Master
Joined: Jan 2006
Posts: 6,564
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From: Woodstock Georgia
Drifting
Joined: Nov 2005
Posts: 1,324
Likes: 5
From: Charlotte NC
I would think that if you did swamp the opti, you wouldn't get it to restart so quickly. Plus, you say the car has been hesitant to start prior to the 'puddle'.
I'd check your codes first off.
Plugs could be fouled, fuel filter, injectors...could be as simple as plug wires grounding out (Ask me how I know that
).
I'd check your codes first off.
Plugs could be fouled, fuel filter, injectors...could be as simple as plug wires grounding out (Ask me how I know that
).
Melting Slicks
Joined: Oct 2004
Posts: 2,510
Likes: 4
From: Austin Texas
25mph through standing water is a pretty good clip. You probably got water splashing which doused you coil. Bottom line, it sounds like you got water on an electrical circuit which temporarily shorted something. If you don't have any future problems such as stumbling and/or erratic idle, your Opti is probably OK.
What may have happened is that the front spoiler scooped up water which made it through the radiator and your fan sprayed the front of the engine. Your battery should be fine and not the cause of this mishap.
What may have happened is that the front spoiler scooped up water which made it through the radiator and your fan sprayed the front of the engine. Your battery should be fine and not the cause of this mishap.
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
It sounds like the water may have damaged your opti. But, the hard starting sounds fuel related. Do a fuel pressure leakdown test to see if the fuel pressure regulator and fuel pump are working properly.
Last edited by STL94LT1; Feb 16, 2009 at 03:42 PM.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Suggestions:
Check fuel pressure.
ICM possibly defective.
Run engine in the dark to see if there is any arking from the plug wires or coil wire near water pump.
I would not jump at the opti quite yet as I agree with the others as stated in their analysis.
Off the cuff if the engine died you would have to loose fuel pressure or spark almost completely. Next time its hard to start I would immediately check for spark and see if anything turns up.
Check fuel pressure.
ICM possibly defective.
Run engine in the dark to see if there is any arking from the plug wires or coil wire near water pump.
I would not jump at the opti quite yet as I agree with the others as stated in their analysis.
Off the cuff if the engine died you would have to loose fuel pressure or spark almost completely. Next time its hard to start I would immediately check for spark and see if anything turns up.
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Thread Starter
Pro
Joined: Sep 2000
Posts: 535
Likes: 19
From: California
Update - 2/17
The car started fine on my way home from work yesterday, so I drove it to the train station today.
Starting it up this evening (to come home), the car would crank, but not fire. As I was cranking the car, I was getting weird readings - partial digits and crazy-looking symbols from the gas gauge/digital speedometer/odometer cluster. Sometimes the car bucked, like it was getting some ignition. Other times it would crank with no sounds of combustion.
I cranked the car at least 15 times, without it starting before I gave up and called AAA. While I was waiting for the flatbed, I tried to start the car one more time and it eventually fired up so I was able to drive it home.
I need to do a serious look under the hood this weekend.
Starting it up this evening (to come home), the car would crank, but not fire. As I was cranking the car, I was getting weird readings - partial digits and crazy-looking symbols from the gas gauge/digital speedometer/odometer cluster. Sometimes the car bucked, like it was getting some ignition. Other times it would crank with no sounds of combustion.
I cranked the car at least 15 times, without it starting before I gave up and called AAA. While I was waiting for the flatbed, I tried to start the car one more time and it eventually fired up so I was able to drive it home.
I need to do a serious look under the hood this weekend.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Almost kinda sounds now like a bad electrical connection. Could be a voltage feed or ground. You might start checking the fuseable links (by the battery) for corrosion or loose connections. There are also some grounds in the area by the removable battery panel.
I would look around inside and outside and see what I could find. Perhaps start the engine and start moving or pulling wires everywhere and see if you can make a change or kill the engine. I would listen to see if the pump runs in the tank for the 2 seconds, might give you a clue if it does not. Sounds like you will be chasing this one down.
I would look around inside and outside and see what I could find. Perhaps start the engine and start moving or pulling wires everywhere and see if you can make a change or kill the engine. I would listen to see if the pump runs in the tank for the 2 seconds, might give you a clue if it does not. Sounds like you will be chasing this one down.
Thread Starter
Pro
Joined: Sep 2000
Posts: 535
Likes: 19
From: California
Update
Suggestions:
Check fuel pressure.
ICM possibly defective.
Run engine in the dark to see if there is any arking from the plug wires or coil wire near water pump.
I would not jump at the opti quite yet as I agree with the others as stated in their analysis.
Off the cuff if the engine died you would have to loose fuel pressure or spark almost completely. Next time its hard to start I would immediately check for spark and see if anything turns up.
Check fuel pressure.
ICM possibly defective.
Run engine in the dark to see if there is any arking from the plug wires or coil wire near water pump.
I would not jump at the opti quite yet as I agree with the others as stated in their analysis.
Off the cuff if the engine died you would have to loose fuel pressure or spark almost completely. Next time its hard to start I would immediately check for spark and see if anything turns up.
I checked with the aid of a friend, and the wire that goes into the coil is arcing when I try to start the engine. The arcing appears to be coming from between the wire boot and the coil itself.
Do you know if this indicates a bad coil or both a bad coil and idle control module?
Racer
Joined: Jun 2006
Posts: 408
Likes: 0
From: Elkton MD
Spark at coil wire
"I checked with the aid of a friend, and the wire that goes into the coil is arcing when I try to start the engine. The arcing appears to be coming from between the wire boot and the coil itself."
The arcing between the wire boot and coil sounds like the wire is bad (main high voltage feed from coil to opti).
The arcing between the wire boot and coil sounds like the wire is bad (main high voltage feed from coil to opti).
Team Owner
Joined: Oct 2000
Posts: 96,443
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From: Fort Knox, KY
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"I checked with the aid of a friend, and the wire that goes into the coil is arcing when I try to start the engine. The arcing appears to be coming from between the wire boot and the coil itself."
The arcing between the wire boot and coil sounds like the wire is bad (main high voltage feed from coil to opti).
The arcing between the wire boot and coil sounds like the wire is bad (main high voltage feed from coil to opti).
You can replace with original ignition wires or go aftermarket in the 7 mm to 8 mm thickness at your local auto parts store.
Might as well do the plugs, too, while you're in there. I like the NGK TR55 in the Double Platinum flavor. Do one wire at a time so you don't cross-wire anything. Don't forget the anti-seize compound for your plugs (aluminum heads).
You will also need to replace the plug wire holders and looms. The ones on your car now are old and brittle and will break when you remove the old wires.
You can order them online from Mid-America Motorworks (MAM). See pic below.
Thread Starter
Pro
Joined: Sep 2000
Posts: 535
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From: California
Update
Yesterday I left the new Opti on the car, bolted up the balancer, replaced the wire from the Opti to the coil, and installed the waterpump. Torquing the balancer bolts properly was great fun. For some reason it took me 7 hours to do all this. I tested the car before replacing the waterpump and it started right up.
I know I should have gone ahead and replaced the plugs and wires since I was in there, but I got anxious to finish the project, so I skipped replacing the plug wires. As I was refilling the radiator overflow tank, I heard the sound of running water (not good) - water was running out of the waterpump where it meets the block on the passenger side! Upon closer inspection, it appears the gasket got kinked, and I think I didn't apply enough gasket sealer either.
So, next weekend, the waterpump comes back off. At least I'm getting better at removing and re-installing the waterpump. And this time I'll remove the serpentine belt tensioner before installing the waterpump!
I know I should have gone ahead and replaced the plugs and wires since I was in there, but I got anxious to finish the project, so I skipped replacing the plug wires. As I was refilling the radiator overflow tank, I heard the sound of running water (not good) - water was running out of the waterpump where it meets the block on the passenger side! Upon closer inspection, it appears the gasket got kinked, and I think I didn't apply enough gasket sealer either.
So, next weekend, the waterpump comes back off. At least I'm getting better at removing and re-installing the waterpump. And this time I'll remove the serpentine belt tensioner before installing the waterpump!
Advanced
Joined: Jun 2005
Posts: 99
Likes: 0
From: Conroe Texas
I'm having similar problems,,with opti or coil..I dont want to dish out the dough if not needed..My 93 LT1 was running fine, added coolant, was burping the system and coolant finally came out way to fast... Squirting all over coil opti, and lots of wiring all in a 6 inch area.. Ultimately killing the motor dead in it's tracks..How did you check the coil??? Im not getting any spark from it,,but I could be doing it wrong...
