Hey guys I'm new here. my dear friend just lost her husband and son last month so she was left with alot of cars and other debt. This grand national is one of them. Has 80k on it and is almost mint. 10 years ago he bought this car and it seems to cut out very bad under boost. Well it has sat till today. Got it started and drove it home to try to fix the cutting out problem. It runs and drives down the road perfect and also setting it park it will rev to redline fine but when ya hammer down and the boost come up it will start cutting out at about 3500 RPMs and will not rev higher till ya let off and let the boost drop. Just trying to help her out with all her cars because she has to sell them all to pay for both funerals. Anybody ever heard of this before? This one has be baffled. It also lost the power brakes but just got that fixed. stuck pressure sensor. thanks in advance for any help.
87 grand national cutting out bad under boost
- Thread starter mvvette97
- Start date
michael evans
Well-Known Member
- Joined
- Feb 27, 2008
Had a problem just like this and replaced had to end up replacing parts know to be new.
Bought car that had new spark plug wires that were supposed to be new and an AC Delco coil in the box new. Turned out that those parts plus the spark plugs I recently replaced were bad.
I don't know how old the ignition parts you have are, but the symptoms are the same as I had.
Bought car that had new spark plug wires that were supposed to be new and an AC Delco coil in the box new. Turned out that those parts plus the spark plugs I recently replaced were bad.
I don't know how old the ignition parts you have are, but the symptoms are the same as I had.
SCOOBY DOO
BASED CANADIAN PATRIOT!!
- Joined
- Feb 18, 2007
Possibly ignition module while the engine is under load.
- Joined
- May 26, 2001
The first thing I would check is fuel pressure.
An ignition issue will not normally not blow a head gasket, but lack of fuel will certainly cause damage especially under boost.
If you need some help, call me at 602-866-9908.
An ignition issue will not normally not blow a head gasket, but lack of fuel will certainly cause damage especially under boost.
If you need some help, call me at 602-866-9908.
Thanks man. I will check the pressure. Should it be around 45lbs? Hate to bother you but I may have to give ya a call sometime. I just want it to run right so she can get more money for it. She didn't want to sell it but with two funerals and hate to say but one more "her father" in the very near future she just cant keep it.
- Joined
- May 26, 2001
The base fuel pressure at 45 PSI is fine at idle, it should increase one PSI as boost increases pound for pound.
At 10 PSI boost, FP should be 55 PSI, and so on as boost increases.
At 10 PSI boost, FP should be 55 PSI, and so on as boost increases.
Might be best to have the car looked at by someone in your area reputable for Buick's before damage is done if it's not already. There's no reason to redline a car at idle or drive around hammering on it knowing it has an issue. It's a Buick, pull the pin and wait for it to explode....
Thanks man. Good to know. Now if I remove the hose of the regulator at idle it should go up in pressure shouldn't it? Like say it's running about 45 pounds with the hose off the regulator then would that be a good indication that the pump is weak?
i
hear ya man. I'm not ripping on it. I was just hoping it was the old gas that was in it. I changed the fuel and drove it to my house about 10 miles and stomped into it to see if it still had the problem. It did so I just drove it easy on the way home. I wish there was somebody near here that knew these cars well but no such luck. this car is loner in this part of the country.Might be best to have the car looked at by someone in your area reputable for Buick's before damage is done if it's not already. There's no reason to redline a car at idle or drive around hammering on it knowing it has an issue. It's a Buick, pull the pin and wait for it to explode....
65psiboost
Member
- Joined
- Oct 25, 2017
I’m sorry to hear about the loss of your friend’s family. Having lost a child myself it hits home for me.
Yes it definitely sounds like it’s choking on low fuel pressure under load.
Yes it definitely sounds like it’s choking on low fuel pressure under load.
- Joined
- May 28, 2001
Sitting for 10 yrs..
Stay off the boost, or, as Nick said, it's head gasket, or worse.
The "find someone that knows what they are doing" suggestion, is lots cheaper than a new engine.
Well I checked the fuel pressure and it jumps from 25 to 30 pounds. I pulled the regulator hose off and it made it to about 33 if that.. Never even got close to 40 pounds. That saying is it safe to say the fuel pump is weak? I checked the filter and it's fine.
NY Twin Turbo
All the good stuff.....Times 2.
- Joined
- Dec 10, 2014
That's no where close to where it needs to be. Park it.
Go through it totally. Check all the fuel lines from front to back, test the regulator with a regulated air source, change the filter, but most likely you will need to drop the tank. Check the rubber lines that come off the pump in the tank. If that stupid silly pulsation/sound killer thingy is still there, throw it away and replace it with strait line. Cut that little section of necked down fuel line out. Buy a new performance pump, get a hot wire kit. Whatever you do.....just be sure it has the fuel it needs. One more little "cut-out under boost" could be the end.
Call Nick, if you have to.
Good luck. I hate to here about a perfectly good car blow up because of a perfectly silly little problem.
SCOOBY DOO
BASED CANADIAN PATRIOT!!
- Joined
- Feb 18, 2007
Stock regulator?
yes stock
pulsation/sound killer thing? Is that in the tank by the fuel pump? The car isn't going to be drove till it's fixed. I'm just trying to fix it so she can sell it.
Thanks bud. Yes she is having a very bad time. that's why I am helping her with these cars. So many people have tried to jump in and offer her pennies on the dollar for this car plus all the others. Very upsetting. I feel your pain when you said you lost a child because my son passed back on 2001. Very hard.
65psiboost
Member
- Joined
- Oct 25, 2017
I know all about the lowballing the widow scams as well. My dad bought a brand new 86 GN. From what I remember it was all he talked about while he was waiting for his Astro roof model. Well long story short he got it. Drove it round trip Brooklyn ny to Florida Disney and back to Brooklyn. And he got to drive it a few times after. He passed a few months after he got the car unexpectedly. On his death bed he wanted me to have his car. So my uncle (his brother) peeped it for a long storage and showed me how to look after it. The whole time my mom who never saw any other man in her life had you know like maintenance people to fix things around the house. And I kid you not just about all of them offered lame ass cash right now offers for the car. And I’m proud to say my mom told them all to go to hell.
Fast forward to February 1990 on my 16th birthday I got my learners permit to drive. That night my mom (who hadsbalso passed in 97) handed me the keys and title to the car. It’s the greatest thing i own in my life. Very low miles. I only take that one out on a very special occasion. But I’ve been offered 35 grand cash for it. But no amount of money can take that from me. And 31 years later it still drives like new. (I have 2 other GNs) so I have my fun with those ones. Unfortunately my dad was a NYPD transit cop so I didn’t see a lot of him but all I can remember was how he talked about buying that car. And whenever I drive it I feel his presence sitting shotgun lol.
I applaud what you are doing for your friend. If you where local I would be there helping you. But I moved to Florida a few years ago. Best of luck to you and her. I’m so sorry about your son. When I lost my baby daughter I had developed a problem with taking too much pain medication but thank God my wife and family helped me get back to my regular dose before it progressed to anything that would land me in jail. But it seems like we have a lot in common. If u ever need to talk message me for my number.
Have a blessed day
Bill
