AfterMarketNews Auto Care Pro AutoProJobs Brake&Frontend BodyShopBusiness Counterman EngineBuilder Fleet Equipment ImportCar Motorcycle & Powersports News Servicio Automotriz Shop Owner Tire Review Tech Shop Tomorrow's Tech Underhood Service

Thorough Brake Inspections Are Comeback Preventers And Profit Builders

How many times have you seen a hand-painted sign in a shop window that advertised a menu-priced brake pad replacement for “$XX.95 per axle.” Of course, a menu-priced brake replacement would be good if a simple brake pad replacement would cure all...


Air Filter Show & Tell: Seeing Is Believing

Air filters are normal wear items that ­require regular checks and ­replacement. Their role is to trap dirt particles that can cause damage to engine cylinders, walls, pistons and piston rings. In fuel-injected vehicles, the air filter also plays...


Build The Car Of Your Dreams In Quaker State Contest

At Quaker State, we know that happiness can’t be bought—it’s built part by part. That’s why we want to give you the opportunity to win a classic truck and customize it to the next level. Through the “Build The Car of Your Dreams” contest,...


The Connected Vehicle: Exploring The Next Frontier in Vehicle Communication

How Technology is Enhancing Vehicle Communication With The Connected Vehicle Connected vehicles have been with us since 1996 when GM introduced OnStar. This first-generation connected vehicle system pioneered the way for similar systems that were to...


ECU Diagnostics

ECU Diagnostics: 1976 Datsun (Nissan) 280Z Call me old-school, but imagine my surprise this spring when a retired “friend of a friend” car collector called about diagnosing a 1976 Datsun (Nissan) 280Z sports car. The collector purchased the 280Z...


Volvo AWD With Active On Demand Coupling

Volvo AWD System Diagnostics When I started driving way back in 1977, it seemed like you had to buy a truck to get a 4WD vehicle. Actually, the first 4WD car was built a long time ago in 1903 by the Spijker brothers. The first commonly produced 4WD...


Anti-Sway Bar Repair and Service

Anti-Sway Bar Technology Anti-sway bars (aka sway, stabilizer or anti-roll bars) never get the credit they deserve. If anti-sway bars were never invented, the ride and handling of vehicles would be a lot more harsh than it is today. That is because...


EPB Diagnostics

EPB Systems and Diagnostics A growing number of vehicles are equipped with electronic parking brakes (EPB) that automatically engage the parking brake when the transmission is shifted into park or it detects that the vehicle is on a hill. If you are...


2010-2013 Kia Soul Brake Repair

The 2010-2013 KIA Soul has one of the most trouble-free brake systems on the market. But, when some Kia Souls begin to push 50,000-70,000 miles, they can suffer more from cheap brake pad slaps and a lack of service to the calipers, ABS system and brake...


Sorting Through Multiple Codes On A Chevy

“My dash lights up like a ­pinball machine, the ­engine loses power for a few seconds, and then seems to run OK.” Although I’d actually been chasing this Diagnostic Dilemma for the better part of a year, this four-wheel drive 2001 Blazer equipped...


Red Kap Welcomes Troy Ladd of Hollywood Hot Rods to The Craftsmen Series

Red Kap has selected L.A. Roadsters 2012 Builder of the Year Troy Ladd as the third custom car icon to be added to the growing stable of Red Kap Craftsmen. Ladd owns Hollywood Hot Rods in Burbank, CA, and has been designing, building and restoring incredible...


Identifix Celebrates 50,000 Direct-Hit Subscribers with 50K Giveaway Contest

Identifix, Inc. has reached another milestone: its 50,000th subscriber to Direct-Hit, its award-winning online tool. To commemorate the occasion, the company has launched a contest called the 50K Giveaway. Five Direct-Hit users who submit a Hotline...


Home Engine Servicing GM’s 3800 V6 Engines

Print Print Email Email

The Buick 231 cu. in. 3.8L V6 engine has had a production run lasting more than 30 years. Like the small block Chevy V8, this engine has undergone many changes over the years to keep it abreast of changing consumer expectations and emissions regulations.

The first Buick 3.8L was offered in the 1975 model year Skyhawk, Apollo, Century and Regal. The engine was based on an earlier 198 cu. in. V6 that Buick introduced back in 1962. The 3.8L engine shared the same 3.8” bore size as the Buick 350 V8. It also had an “odd-fire” crankshaft, which produced some idle shake and vibration.

Over the years various improvements were made to upgrade engine performance. Here are some of those changes:

1977 — Buick changed to an “even-fire” offset-pin crankshaft to smooth out the V6 engine.

1978 — Turbocharged version of the 3.8L V6 offered in the Buick Regal and LeSabre.

1979 — The engine gained some horsepower with improved cylinder heads (larger valves and ports).

1980 — Larger 4.1L version of 3.8L engine offered with bigger 3.965” pistons.

1981 — Stronger connecting rods and a revised harmonic balancer and flywheel were added.

1982 — 180 hp version of the turbocharged 3.8L V6 offered in Regal T-Types and Grand National. Also, a smaller displacement 3.0L version of the 3.8L V6 with a shorter stroke crankshaft was built for GM FWD cars.

1984 — Direct fire distributorless ignition and electronic multiport fuel injection were added. Also a new camshaft with a larger base circle and 0.015” shorter pushrods were added. This was also the first year for a front-wheel drive (FWD) version of the 3.8L V6.

1985 — The engine was refitted with a single serpentine belt to drive its accessories. The number of bolts on the oil pan was also increased from 14 to 20 to reduce oil leaks. The head bolts also changed to non-reusable torque-to-yield bolts.

1986 — The flat tappet lifters were upgraded to roller lifters to reduce internal engine friction, and sequential fuel injection was also added for improved performance, fuel economy and emissions. The deck height of the block was also reduced 0.035” to accommodate thicker composition-style head gaskets. Some FWD versions of the 3.8L V6 (VIN 3) were offered with roller lifters. FWD versions also got new cylinder heads with pedestal-style rocker arms, and a needle bearing thrust washer for the camshaft.

1988 — Buick now dubbed the engine the 3800. The block casting was revised and a balance shaft added to dampen vibrations. The cast iron camshaft was replaced with a steel camshaft, thinner, low-tension piston rings were added to reduce friction even more, and the mechanical EGR valve was replaced with an electronic digital EGR valve to reduce NOx emissions.

Pages: 1 2 3Next page

The following two tabs change content below.

Larry Carley

Larry Carley has more than 30 years of experience in the automotive aftermarket, including experience as an ASE-certified technician, and has won numerous awards for his articles. He has written 12 automotive-related books and developed automotive training software, available at
  • Chris

    I have a 2002 Buick Park Avenue that gets warm (doesn’t overheat) and stalls when idling. It won’t start again until it cools down. This started 10 months ago and now occurs after only 15 miles or so of driving. A good dose of water in the area of the coil pack/crankshaft helped and so I replaced the ignition module with no effect (it needed the new grease). Based on other’s experiences, it seems the crank sensor is a likely culprit, so I bought AC Delco part 10456161 and replaced it. The car then would crank but not even start. That part was sent back and the same part was purchased elsewhere, with the same results. Both times, the original part was reinstalled and the car started. I know there’s a system variation learn procedure that you’re supposed to have done (some folks say they skip it), but it has to be done after the car is running and the temperature is up to 158 degrees. Why is the car not starting?

    • Evilcowboy420

      Three things an engine requires to run is spark, fuel and air. But I stand that 4 things are needed as well nowdays it includes the computer. Your crank sensor is bad. You replaced it and the car didn’t start. Thats your computer telling you it needs the relearn procedure done. I would suggest looking that up and doing that but if you don’t want to do that dance then unplug the negative to the battery for 10 minutes after installing your new sensor. This should reset the computer back to defaults then it will have a base line for cranking the engine with the new sensor. You confused it by putting in a working one. The computer accounted all it could for the one failing until the car got worse. So the computer thinks it still has a bad one connected and needs to be accounting for the bad one. By resetting the computer your giving it an opportunity for it to do its thing and relearn it over again.

      The computer makes adjustments slowly over a period of time and values will change until the part that fails craps out and the computer cannot do anything more to help the situation. Hence the no start condition with a new one. When you put the same old one back in it is already calibrated for the crappy one and will start.

      Save yourself a lot of problems and do the relearn after the new one is installed.

      Second as for the overheating issue. Who told you water was good to put on a coil pack? Water is an excellent conductor of electricity never a good idea to mix the two. This brings me to you testing out to make sure the coil pack is still good as well as that can cause your no start as well. They run hot and can fail. So check that out. Overheating issues are caused by several things even if it is a slight overheat it is still rising above normal. With these problems use of a digital multimeter can help rule out coolant temp sensor. Usually you want to start small and cheap replacing stuff until you get the right component. Start with a thermostat if that dont help do the CTS then the water pump and then the intake gaskets. More than likely your gaskets have a leak since it is a very common problem. Replace both lower and upper intake gaskets and have the plastic part checked for warpage and replace if necessary.

      Anyways I speak from experience with this engine both the old and new ones. I got a 2004 lesabre and a 89 bonneville. The 04 Lesabre runs like a top with no check engine lights on. The 89 Bonnie is having it’s engine rebuilt by me. So I am pretty knowledgeable when it comes to these engines.

      Anyways good luck

      • Odetta McNabb

        my 1995 buick lesabre has a stumble during acceleration high and low speeds,intermittently….3800 v6 f.i. any ideas? tune up and fuel filter and new gas cap no help.

        • Evilcowboy420

          Glad you found the problem I would have said FPR. Also it would be a good idea to check your engine mounts on a car that old. As a bad dog bone mount can cause the engine to roll back on acceleration and mimic a stumble or jerk.

          If you ever experience the same symptoms again don’t condemn the FPR and pump right away as other cheaper things can cause the same condition. Any reputable mechanic that is worth their weight in gold will tell you always start cheap and the move up in cost.

          Anyhow I am glad to hear you got to the root of the problem. Good luck it may be an old car with an older engine in it but I an tell you there is no way that car is even close to dying. The 3800 engine is the type of engine you could probably chuck a wrench in the crankcase and it would chew it up and spit it out and want more abuse. It is a very forgiving engine and stands up to just about any kind of abuse you can throw at it. I was actually very surprise that the 89 bonneville I have spun a bearing because it is extremely uncommon on the engines but it was very apparent that it was beyond abused. lol Oh well new crank and she lives again.

  • buickrepairer

    I was trying to remove the supercharger snout without removing the whole supercharger. I think just my outside bearings are bad. I have loosed/removed all bolts that I can see and still can’t get the plate off in front of the snout that holds the tensioner pulley. Any ideas?

  • dkthree

    I have a 98 Pontiac Grand Prix with the 3.8, great engine. It started leaking after warmup lately, but I can tell where the leak is coming from. No white smoke, so I don’t think it’s the manifold gasket. Not the water pump, no leaks all around. Any ideas?

    • James

      When you have no leaks dude it is being dumped into the engine. Sorry to say. You may not see white smoke but that just means coolant is not being burned it don’t mean it isn’t dumping into the crankcase with the oil. Just buy the updated gasket set and plan for the job on a weekend and then enjoy another 5 to 10 years of trouble free 3800 fun. If the gaskets haven’t been changed you should just change them as GM even admitted the OE gaskets weren’t good and recommends you change them.

  • Fred

    Hello. I have a Grand Prix GTP 1999 with 210000 kms. When I accelerate the vehicle starts to shake. I have a feeling it is either the spark plugs or the supercharger. It starts shaking when it just starts to show I have boost. Other than that when I’m just maintaining normal speed without accelerating it drives just fine. Does anyone know anything about this? Thanks

  • John

    I have a 2007 pontiac Grand Prix had a coolent leak so I replaced the two plastic elbows with metal ones problem gone for about 2 weeks then the water pump started leaking so I replaced it worked fine no leaks for about a month then noticed a leak did not no where it was coming from so I replaced the water pump again no leaks for about two weeks now its leaking again not sure from where any ideas

  • Arzola

    I have a 1994 bonneville ssei 3800sc
    First off my car was driving under power :no pickup & you can’t hear the supercharger whine . I was driving home and it sputtered then acted like it was going to die then was fine parked it then it wouldn’t stay started only kept dying no it won’t start.
    I took off the throttle body and cleaned it very well and still at a loss I recently replaced my fuel pressure regulator & fuel filter but that’s all

  • Heith Inghels

    I have the 1989 Oldsmobile delta 88 royale brougham. After market parts are the coil pack, ignition control module, mass air flow sensor. When I did coil pack and ICM, I also replaced spark plugs and wires. As well as put in a new alternator. Engine runs splendidly. I use a full synthetic oil, for the motor and transmission. Engine is passing 226,000 miles.

  • kendall martens

    i have a 2007 grand prix with 3.8 motor…engine light came on and i had it looked at…autozone said it was the #2 cyclinder misfire…put new plug and new wire. also a new ignition coil, also modual…my mechanic said it could be my injector next and that i could probably do that…

    so could it be my injector, and could i do it, and where is it?..
    it runs rough at idle but better at 70 or 80…

    Thank you

  • Sam Summers

    I have a 1994 buick regal GS 3800 and I can not find the ground wire short that keeps the car from getting hot in the summer time

  • Staci Gaddis

    I have a 2001 buick lesabre and I have changed out the ignition control module after she lost power and she has full power, doesn’t misfire but she is difficult to start up in the morning. She doesn’t turn over. There is no engine codes. Any ideas ?

  • Mike

    Im changing the starter on a 96 buick lesabre with the 3.1l engine, any tips suggestions

  • Constance

    I have 2002lesaber 3.8motor I’m not sure what is wrong with it I’m not sure if my transmission needs flushed or if its something else but the motor or the RPMs read really high and it felt like it jerked and it died it’ll start I haven’t tried to drive it

Latest articles from our other sites:

JohnDow Industries, Jaguar Land Rover-North America Create Vendor Partnership

Representatives of Jaguar Land Rover-North America LLC, based in Mahwah, New Jersey, announced an enhancement to its longstanding vendor relationship with JohnDow Industries (JDI) at its recent New Orleans...More

OTC Offering Technicians A Chance At 'Ultimate Diagnostics For Life' Package At SEMA 2015

OTC will be offering technicians a chance to win the “Ultimate Diagnostics for Life” package at SEMA this year at booth No. 16007 at the Westgate Hall in Las Vegas. Part of the nationwide Technician...More

The Connected Vehicle: Exploring The Next Frontier in Vehicle Communication

How Technology is Enhancing Vehicle Communication With The Connected Vehicle Connected vehicles have been with us since 1996 when GM introduced OnStar. This first-generation connected vehicle system pioneered...More

Autologic Diagnostics Launches Autologic Assist

Autologic Diagnostics, a global provider of aftermarket automotive diagnostics solutions, announced the introduction of its new Autologic Assist fix and support system. Autologic Assist is designed to...More

The Future of All-Wheel Drive Vehicles

What's Coming Next With All-Wheel Drive Vehicles? The future of all-wheel drive vehicles was not that bright five years ago. With looming fuel efficiency mandates facing the industry, all-wheel drive...More

Alltech Automotive To Introduce New Strut Assembly Program At AAPEX

Alltech Automotive, a premier supplier of quality automotive aftermarket replacement products, will be presenting a brand new strut assembly program during AAPEX in Las Vegas. “Alltech Automotive...More

JohnDow Industries, Jaguar Land Rover-North America Create Vendor Partnership

Representatives of Jaguar Land Rover-North America LLC, based in Mahwah, New Jersey, announced an enhancement to its longstanding vendor relationship with JohnDow Industries (JDI) at its recent New Orleans...More

OTC Offering Technicians A Chance At 'Ultimate Diagnostics For Life' Package At SEMA 2015

OTC will be offering technicians a chance to win the “Ultimate Diagnostics for Life” package at SEMA this year at booth No. 16007 at the Westgate Hall in Las Vegas. Part of the nationwide Technician...More