My first grand national

Stevens65

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Aug 18, 2018
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Hi guys , just bought a 87 gn from original owner in Ohio , car has 76000 original miles the owner hardly drove vehicle in past 10 yrs due to health reasons , car is in excellent condition motor ? Upon road testing heard knock from engine when I got on it , so I laid off didn’t want to push it , owner said he always ran 87 octane ... and the fuel is old , Should i pump out the fuel and run 93 in it and drive it gently for a tank or two then change plugs , fuel filter , coil pack wires and knock sensor? Want to keep it stock to certain point , just don’t want pinging if I want to get on it once in a while , thanks guys oh yeah I’ve been reading scanmaster is on the way
 

mikestertwo

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Sep 13, 2006
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Just drive it gently for a couple of tanks of 93. Get a more modern chip for the computer if it already doesn't have one. No need to change the knock sensor. No reason to change the coil pack and wires unless they test bad. Change the fuel filter and plugs. Depending on what your goals are for the car there are a few upgrades that will improve drivability.
 
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Stevens65

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Aug 18, 2018
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Just drive it gently for a couple of tanks of 93. Get a more modern chip for the computer if it already doesn't have one. No need to change the knock sensor. No reason to change the coil pack and wires unless they test bad. Change the fuel filter and plugs. Depending on what your goals are for the car there are a few upgrades that will improve drivability.
Just drive it gently for a couple of tanks of 93. Get a more modern chip for the computer if it already doesn't have one. No need to change the knock sensor. No reason to change the coil pack and wires unless they test bad. Change the fuel filter and plugs. Depending on what your goals are for the car there are a few upgrades that will improve drivability.
Ok thank you
 

Pronto

Chaos is a ladder.
Dec 9, 2002
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Welcome to the board. Please, please drain that gas out and use ONLY 93 if you can get it. These cars were built when high octane was available and the the stock chip has way too much timing for 87 octane. Unfortunately if the previous owner has only run 87 for extended periods of time you could be in for a sad situation. Dentonation will destroy the engine in no time flat and this has been going on for a long time. I bet if you pulled the sparkplugs you'll see a bunch of aluminum specs on the tip of the plugs. I would at least pull the pan and look at the bearings. If they are hammered to death then you'll know how bad runnning 87 is. I don't mean to scare you but if the owner was that foolish then God knows what else is wrong with the car. I would search out a Buick guru in your area that can help you sort through this. You should do the "spring cleaning" in the meantime. You can do a search for the proceedure.
On a side note, this post should be in the general tech secton or member introductions. This area if for how someone has done mods or repairs and sharing the "how to" to the members.
 
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Stevens65

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Aug 18, 2018
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Thanks much , haven’t had time to do anything yet , 93 is available over here , I’ll drive her gently for a couple of tanks , idles fine and ran good , it was when I got on it , fingers crossed , thanks
 

Pronto

Chaos is a ladder.
Dec 9, 2002
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When my friend accidently filled up with 87 he couldn't go into any boost with out knock showing on the Scanmaster. Once you hear pinging your already doing harm. The stock boost gauge is a joke. Don't go by that. Get a real boost gauge so you can be sure what your boost is doing even if you car keeping it stock.
 

seedling

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Jun 17, 2012
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Welcome to the forum man! Lots of killer info here! Best thing you can do is to forget you ever knew anything about cars, as you’ll soon learn that Turbo Buick’s are totally different than most anything out there! And you can’t apply Small Block Chevy mentality to a Turbo Buick! Just saying, it happens as we all have done it!!

The best assessment or way to prepare your car for the road, was mentioned earlier and that “SpringCleaning”! Especially if your car sat for ten years! There are other upgrades you’ll want to make later just to make it safe. However, this is a must and it’s first!!

http://www.gnttype.org/maint/basics.html

Good luck and enjoy!!


Sent from my iPhone using Tapatalk
 

Stevens65

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Aug 18, 2018
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Sweet thanks for the link, I have a little work to do first ... can’t wait thanks again for your help , I’ll definitely keep you posted
 

Stevens65

New Member
Aug 18, 2018
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Welcome to the forum man! Lots of killer info here! Best thing you can do is to forget you ever knew anything about cars, as you’ll soon learn that Turbo Buick’s are totally different than most anything out there! And you can’t apply Small Block Chevy mentality to a Turbo Buick! Just saying, it happens as we all have done it!!

The best assessment or way to prepare your car for the road, was mentioned earlier and that “SpringCleaning”! Especially if your car sat for ten years! There are other upgrades you’ll want to make later just to make it safe. However, this is a must and it’s first!!

http://www.gnttype.org/maint/basics.html

Good luck and enjoy!!


Sent from my iPhone using Tapatalk
Thanks so much man , I’m listening to all you guys you guys are very knowledgeable and I trust you , I’ll keep you posted
 

Stevens65

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Aug 18, 2018
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Thanks , I’ve called around here in northeast Ohio , can’t seem to find any shop that will work on my gn , I’ll take the advice of everyone and do it myself
 

Pronto

Chaos is a ladder.
Dec 9, 2002
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You definitely want a shop well versed in Turbo Buicks. I'm sure there are members here from your area that would be willing to lend a hand or at least point you to reliable shops. Maybe post in the "Regional" section looking for where to go...
 
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