Roadmaster w/ LT1 having ignition issues
01-24-2011, 05:15 PM
#1
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Roadmaster w/ LT1 having ignition issues Hi all,
My friend has a 1995 Buick Roadmaster with an LT1. On Saturday the car stalled out and wouldn't start until the engine cooled down a little, but then still ran fine. Prior to it stalling there were no performance issues, etc.
Based on the symptoms (and the fact that a day later the car ran great until it came up to temperature and held for a few minutes at which point it stalled out and could not be restarted) we are assuming it is a problem with the Opti-spark. The shop that he took it too (the one that replaced the opti. 4 months ago) said it is a problem with the ignition module (or some other external module) and that the "Cap and rotor" are fine and that they replaced the "cap and rotor" last time, not this module.
We think they're full of **** and should replace the opti. on their dime.
What do you think?
Thanks for any/all help in advance!
My friend has a 1995 Buick Roadmaster with an LT1. On Saturday the car stalled out and wouldn't start until the engine cooled down a little, but then still ran fine. Prior to it stalling there were no performance issues, etc.
Based on the symptoms (and the fact that a day later the car ran great until it came up to temperature and held for a few minutes at which point it stalled out and could not be restarted) we are assuming it is a problem with the Opti-spark. The shop that he took it too (the one that replaced the opti. 4 months ago) said it is a problem with the ignition module (or some other external module) and that the "Cap and rotor" are fine and that they replaced the "cap and rotor" last time, not this module.
We think they're full of **** and should replace the opti. on their dime.
What do you think?
Thanks for any/all help in advance!
01-24-2011, 05:57 PM
#2
I know you said you experienced no driveability issues prior to the "event", but did they use a scan tool at all? I had something weird happent to mine and the diagnoses was engine tune, misfire. Dealership was partly correct. Th EGR valve was sticking. If/when this happens again, unplug the EGR vacuum line or push the diaphragm up and make sure it springs down in a smooth, linear fashion and see if it starts. If it does, the culprit is a sticking valve that is diluting the air-fuel mixture with exhaust gas/fumes. Running the car with the vacuum line unplugged will cause the engine to ping under moderate and greater throttle opening. BTW, the EGR is VERY HOT, esp when the motor is or was running! See if this helps! The EGR is serviceable, unless it is broken, you can clean it with carb/throttle body cleaner.
01-24-2011, 07:08 PM
#3
Hi all,
My friend has a 1995 Buick Roadmaster with an LT1. On Saturday the car stalled out and wouldn't start until the engine cooled down a little, but then still ran fine. Prior to it stalling there were no performance issues, etc.
Based on the symptoms (and the fact that a day later the car ran great until it came up to temperature and held for a few minutes at which point it stalled out and could not be restarted) we are assuming it is a problem with the Opti-spark. The shop that he took it too (the one that replaced the opti. 4 months ago) said it is a problem with the ignition module (or some other external module) and that the "Cap and rotor" are fine and that they replaced the "cap and rotor" last time, not this module.
We think they're full of **** and should replace the opti. on their dime.
What do you think?
Thanks for any/all help in advance!
My friend has a 1995 Buick Roadmaster with an LT1. On Saturday the car stalled out and wouldn't start until the engine cooled down a little, but then still ran fine. Prior to it stalling there were no performance issues, etc.
Based on the symptoms (and the fact that a day later the car ran great until it came up to temperature and held for a few minutes at which point it stalled out and could not be restarted) we are assuming it is a problem with the Opti-spark. The shop that he took it too (the one that replaced the opti. 4 months ago) said it is a problem with the ignition module (or some other external module) and that the "Cap and rotor" are fine and that they replaced the "cap and rotor" last time, not this module.
We think they're full of **** and should replace the opti. on their dime.
What do you think?
Thanks for any/all help in advance!
What it is doing now could possibly be the ignition module like they are saying. It is attatched to the front side of the head on the drivers side. It heat soaks pretty good and can crap out when hot. Some ppl solve the issues with it by spacing it out from the head a bit with washers.
01-24-2011, 07:22 PM
#4
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There were no problems with the opti before it was replaced. It was a preventative replacement. They were supposed to replace the whole opti, but the receipt shows only "Cap and rotor"
I'm not sure if they ran a scan. Would the sticking EGR valve show on there?
I'm not sure if they ran a scan. Would the sticking EGR valve show on there?
01-24-2011, 11:38 PM
#5
I hope they didn't charge you the full "opti-swap" service, if all they changed out was the cap and rotor. If they were thinking preventative maintenance they should've swapped out the 'opti while they were in there. In any case, like the others have said the coil is a possibility, but I would also look into possible fuel system issues as well...
