New member, first time poster, longtime GN owner.....could use a little help

[Bob K]

Hello guys and gals. I could use a little help from the group, but first a little info on my car. I'm from Northwest Indiana and have a 1987 GN that I purchased around 1990 as the second owner. The car has 46k miles on it and is pretty much all original. The only things changed other than oil was the spark plugs and spark plug wires and the brake booster (or whatever its called). The plug wires are Magnecor R-100 Racing 10mm wires. The only other changes was adding a K&N filter and a mild chip from Joe Lubrant. I used to be personal friends with Joe and he made this chip for me in the early days of his chip mods. All of the rest of the car is original. All of the rubber, including the tires are original. I did replace one vacuum line a couple of years ago, but that's all. Oh, I did have the headliner replaced a couple of years ago also. The radio has issues, so I don't use it and the power antenna quit working last year, but everything else works on the car, including the A/C with R-12. Now to the problem: First let me start off by saying that I'm not very tech savvy so be kind please. I don't have the "Turbo V-6 for Dummies book". I probably put less than 500 miles a year on the car, mostly going to shows/ cruise nights. For the last couple of years, the car hasn't been running up to par. Not bad, but not normal. I've always put BP Ultimate in it and every other year, I would have to take it in for emissions testing, which it has always passed. A couple of times the check engine light would come on when bring the car out of storage, but would go off after driving it a while. This year, I made the mistake of putting regular gas in it from one of the cheapo gas stations and that's when my problems seemed to start. The car started running rough so I bought a can of octane boost and added it to the fuel. Then I noticed that the check engine light was coming on more frequently, until it just stayed on. The car also stumbles very bad and seems like it wants to die. I bought an Actron code scanner and it showed codes #33 and #44 . I bought a new oxygen sensor and installed it, so I no longer get the #44 code. I bought a spectra Premium Mass Airflow Sensor #MA158 and installed it. The car would fire up and immediately die. The only way to keep it running was to play with the throttle, almost like pumpimg it. I put my MAF back in and the car stays running. If I unplug the MAF , the car stays running. If I drive the car with the MAF unplugged it runs the same as with my original MAF plugged in. Yesterday, I tried an Airtex #5S2628 MAF and it starts and dies immediately like the Spectra Premium did. Could both MAF sensors have been bad or am I looking at the wrong thing? Help me please.... I'm an old school guy of carburetors and points, so be easy on me. I don't know squat about turbos and injectors and stuff. Sorry for the long winded post, but I wanted to try to be as accurate as possible.

 

[TurboBuRick]

Hi Bob,

Chances are slim to none that a parts store maf that will work. Your best bet is to get a lt1 or ls1 maf and a maf translator.

Do you still have the original maf?

 

[Quick6'n'-K.C.]

Bad gas or water in the fuel, heck the car could have a little bit of diesel in it if they fill the tanks at your station like they do here

Put your MAF back on, plug it in and swap out the fuel

 

[GNRick]

Also google tire expiration date. If your vacuum hoses turn your fingers black you might need new hoses. For some good reading on our cars go to Vortex Buick.com. Add zddplus to your oil. Congrats on keeping your car so long!

 

[John Larkin]

I lived in Indy for 13 years; good to see a Hoosier on the board. It is common to get multiple bad reman MAFs in a row - they are a crap shoot. The octane boost will probably turn your sparkplugs red. As recommended, pump out the gas from the tank. There is a test lead behind the alternator hanging there with a black connector. If you put 12 volts to that connector, the fuel pump will run. What you do is on the fuel rail by the fuel pressure regulator on the driver side of the intake, there is a knurled cap. Unscrew this and inside the threaded end there is a schraeder valve like a tire stem valve. Remove this and clamp a hose tightly over the threaded end that is long enough to go over the fender to a gas can on ground - recommend clear hose, you can find it at Menards + a worm clamp. Then apply 12 volts from a jumper wire to the connector and the fuel pump will start pumping fuel. Drain the tank -put some of the old gas in your everyday car a little at a time if you please to get rid of it. Replace with good fuel.

The age of the car is the problem - parts just go bad. Since you are keeping it, do what several have said below and store your original parts.
1. Consider a LT1 MAF + a MAF Translator. It is foolproof modern technology - set it and forget it.
2. Replace all your vacuum hoses - by now they are dry rotted and will cause problems with sensors, etc. Get everything you need in bulk at NAPA.
3. Replace your tires - don't wreck your car from a blowout. Ride over to South Bend and go to Tire Rack. They have some OEM size Yokohama Avids for $70/each.
4. Replace your cooling system hoses - stranded on the side of the road from a weak hose is silly as these are not expensive. I have a whole list of what to buy somewhere. Send me an email and I will share it with you. johnkiml@att.net
5. Replace the fuel pump with a Walbro 340M.
6. Do a spring cleaning from www.gnttype.org - that is a fuel filter, rear differential lube, spark plugs, etc. Go to the site and run through the technical articles.

You'll spend $1,000, maybe less, on all this depending on where you shop but your car will reward you with continued enjoyment. And I woudl still run the Joe Lubrant chip for now.

 

[ITSAV6]

The spring cleaning list off gnttype.org The 87 octane won't make it run crappy just cruising around, will just hurt it under boost with spark knock. X2 on the parts store mafs, mine crapped out in 94 and 3 "rebuilt" mafs that didn't work right I ordered a GM maf. Just took it off last year for a translator and LS1 maf. Great upgrade.

 

[Bob K]

Thanks for the help guys. You really think it could be the fuel? I'm going to go ahead and remove the old fuel and put fresh fuel in it and put the original MAF sensor back on. Hopefully this works. I did look at the hoses and vacuum lines and surprisingly, they seem ok. I also spayed carb cleaner on and around each line and did not detect any leaks. I think I will still take your advice and change the vacuum lines and radiator hoses. I'm not sure that I want to get the LS1 MAF just yet. I know it's also time for new plugs as I haven't changed them in years. What plugs do you recommend and what gap? I will also check out the sites mentioned and I will send you an email John.
John, is the black terminal next to the green one in the pic below the one that you are talking about?

More pics of the car:

 

[V6-Sauce]

Hello guys and gals. I could use a little help from the group, but first a little info on my car. I'm from Northwest Indiana and have a 1987 GN that I purchased around 1990 as the second owner. The car has 46k miles on it and is pretty much all original. The only things changed other than oil was the spark plugs and spark plug wires and the brake booster (or whatever its called). The plug wires are Magnecor R-100 Racing 10mm wires. The only other changes was adding a K&N filter and a mild chip from Joe Lubrant. I used to be personal friends with Joe and he made this chip for me in the early days of his chip mods. All of the rest of the car is original. All of the rubber, including the tires are original. I did replace one vacuum line a couple of years ago, but that's all. Oh, I did have the headliner replaced a couple of years ago also. The radio has issues, so I don't use it and the power antenna quit working last year, but everything else works on the car, including the A/C with R-12. Now to the problem: First let me start off by saying that I'm not very tech savvy so be kind please. I don't have the "Turbo V-6 for Dummies book". I probably put less than 500 miles a year on the car, mostly going to shows/ cruise nights. For the last couple of years, the car hasn't been running up to par. Not bad, but not normal. I've always put BP Ultimate in it and every other year, I would have to take it in for emissions testing, which it has always passed. A couple of times the check engine light would come on when bring the car out of storage, but would go off after driving it a while. This year, I made the mistake of putting regular gas in it from one of the cheapo gas stations and that's when my problems seemed to start. The car started running rough so I bought a can of octane boost and added it to the fuel. Then I noticed that the check engine light was coming on more frequently, until it just stayed on. The car also stumbles very bad and seems like it wants to die. I bought an Actron code scanner and it showed codes #33 and #44 . I bought a new oxygen sensor and installed it, so I no longer get the #44 code. I bought a spectra Premium Mass Airflow Sensor #MA158 and installed it. The car would fire up and immediately die. The only way to keep it running was to play with the throttle, almost like pumpimg it. I put my MAF back in and the car stays running. If I unplug the MAF , the car stays running. If I drive the car with the MAF unplugged it runs the same as with my original MAF plugged in. Yesterday, I tried an Airtex #5S2628 MAF and it starts and dies immediately like the Spectra Premium did. Could both MAF sensors have been bad or am I looking at the wrong thing? Help me please.... I'm an old school guy of carburetors and points, so be easy on me. I don't know squat about turbos and injectors and stuff. Sorry for the long winded post, but I wanted to try to be as accurate as possible.

This happened to me alittle while back, The car fires up then stalls having to hold on the gas pedal to keep running, even with a new maf sensor/fuel pump etc....You may have a big vacuum leak coming from the intake manifold gasket or the injector seals that can cause the car to stall like that, Also check your coil pack. You have a nice car..ps-The lastest chip out there for a mostly stock set up is a TurboTweak v5.7/or commander chip from full throttle speed.com, with a stock MAF sensor. hope this helps

 

[John Larkin]

Yes that is the black connector. You have a nice clean car. Autolite 23, gap @ .028 - .030, use a little anti-sieze on them.

 

[robertf]

I did'nt think it was possible to get 46,000 on those Goodyears but age alone warrants replacing them. Old tires can be dangerous. Very nice car though. How about a pic of that Mustang hiding in the garage?

 

[Bob K]

I did'nt think it was possible to get 46,000 on those Goodyears but age alone warrants replacing them. Old tires can be dangerous. Very nice car though. For the last 20 years or so I've only used the car to go to local cruises and car shows. No burnouts and no racing.
How about a pic of that Mustang hiding in the garage?

Do you mean this car?

 

[Bob K]

It's just my Shelby GT.

 

[robertf]

Yep, that car!

 

[TURBOELKY]

Nice GN, really nice!

 

[Ross L]

Surprised no one mentioned Cottons reman mass air flow sensor. Cost more but exact same as original. If you have your original there is a core charge. Worked perfect on mine and didn't have to do the translator. Good luck.

 

[Ross L]

Or maybe it was Kirbans...

 

[robertf]

FWIW, LS1 MAF/translator are much more reliable longterm.

 

[Coelacanth]

I agree with Robert. The translator and appropriate chip will help the car's performance running on modern unleaded gas. Our cars were built to run on leaded gas from several decades ago, not today's gas.

 

[Ross L]

My original MAF unit lasted almost 30 years. Lol, more reliable than that? Not to argue, but how much better can a car run? And what does leaded gas have to do with it? My drivability is perfect with the stock MAF sensor, turbo tweak chip and bolt-ons. Also 26+mpg on hwy. Maybe someday I'll convert. I'm not saying that translator isn't "better" but orig. poster has mostly stock car, sounds like he just wants it to run right without issues.

 

[Coelacanth]

Mine lasted that long too, but I wanted to upgrade the performance and I wanted my car to run properly on unleaded gas. You think that's meaningless? Think again. My car has about 56K original miles and was otherwise running fine, but I did a ton of research, got a Bluetooth ALDL adapter, ALDLdroid app and logged data on my Android phone and saw a bit of detonation happening. Now anything that could be causing that detonation is still meaningless?

How will you know if your car is "running right without issues" if you aren't logging data and especially looking to avoid knock retard?

I quote; it might not seem so meaningless:

This year, I made the mistake of putting regular gas in it from one of the cheapo gas stations and that's when my problems seemed to start. The car started running rough so I bought a can of octane boost and added it to the fuel. Then I noticed that the check engine light was coming on more frequently, until it just stayed on. The car also stumbles very bad and seems like it wants to die.