Buick - Regal :: Rough Idles And Misfires On Cold Starts

1991 Regal, 3800 v6.

So here's an interesting observation. When i turn the ignition to ON, I hear no sound nor feel any vibration from the fuel pump. Is there any scenario where a fuel pump fails to prime yet kicks into gear after a start? So, I've got rough idles and misfires on cold starts. Before I start replacing parts my diagnostic plans is as follows:

Remove and inspect spark plugs.
Inspect and test starter coil/distributor (still have to research how to do this)
Test resistance on fuel injectors.
Test pressure drop on fuel rails.
Test compression for possible small head leak.

I'm wondering, if I do have a tiny head leak that is letting in a drip or two of coolant after hours of the engine sitting, will I be able to see this on the gauge doing a compression test? I've never done one before and still need to buy a gauge, but maybe I'm better off just doing the other tests and if they all check out I can be certain it is a minor head leak.

My assumption is that I have a leaking injector; just trying to do things the proper way.

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Buick - Regal :: 1993 - Intermittent Hard Start / Idles Roughly

1993 Buick Regal 3.1l V6 Multiport injection

Problem: The care currently has a hard start, and a fluctuating idle. I bought the car a year and a half ago it still has low miles about 94,000. The care used to start fine but had a fluctuating idle in the range of 750 to 2500 rpm. My brother who is a mechanic and doesn’t live near, do all the gaskets when he visited. Then the idle fluctuation dropped to 750 to 1000rpm, when the car rpms fluctuate there is a whirring sound I can hear from the cab, like a pump or pull system. On occasion there is a vibration as well but it is inconstant and irregular. Fuel pressure seems to fluctuate as well. If the car will not start I give it a little gas and it will run fine after a minute or two, but then the idle starts to fluctuate.

No fuse issues I can tell and relays seem to be fine.Checked for lose wiring connections found, none. I have replaced:

- Hoses and gaskets
- Starter motor
- Battery
- Fuel Pressure regulator
- Fuel Filter
- Spark plugs and wires
- TPS
- Idle Air control Valve
- Crank shaft sensor
- PCV.

Right now I’m thinking it could be the fuel pump (a nightmare to change on this car), a fuel injector failing, and the ignition switch.

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Buick - Regal :: Rough Idle Randomly And CEL Came On

I have a 1995 Buick Regal, with a 3.8L engine. When I start the car sometimes it rough idles and I have to give it a lot of gas and then it runs fine. This is completely random. Sometimes it runs just a little rough, other times really rough. The rough idling when starting the car happens about 1 out of 25 times. Sometimes when this happens I get a check engine light, most of the time not. When I am driving around I also will randomly get a check engine light, but I can't tell anything common to it. It has come on while braking, while coasting with foot off the gas and brake, normal city driving, highway driving. Also my CEL always turns off when I turn off the car and doesn't come back when I restart the car. Always.

I haven't been able to figure out what is wrong and since my car is transition OBD1 to OBD2 I can't use a OBD2 code scanner (it is an OBD1 port), nor will shorting the pins in my OBD1 type port give me codes. Being this the case I took it to a local mechanic and they scanned the computer and said they got 16 error codes. They reset the codes but couldn't get the CEL to come back on. I took it drove it for a couple of days the light came back on so I took it back to the shop and they got 18 codes out of it, but they were mostly different, with some of them giving the opposite readings of before (O2 sensor high one time, then low the next check). They said they didn't know what was going on but wanted 3-4 hours to diagnose the PCM (Powertrain control module) and would probably replace the PCM (~500 on top of the diagnostic fee). That was a bit much for me, so I took the car back.

The things I have checked are fuel pressure (seems fine at idle and revving the car in park)Vacuum is 19 and when I rev quick it drops to zero or so then up to 25 and slowly goes back to 19 (I think that means vacuum is ok). I put the gauge in the O2 sensor before the CAT and I didn't read any pressure, so I think the CAT is ok.I put on a new fuel pressure regulator, and a new fuel filter. I got the same PCM at a Pick-n-pull place and put it is my car 3 days ago. Yesterday I got a check engine light while driving again. The mechanic will charge me to check the codes, but I think it is just doing the same thing as always. I am sort of at a loss as what to do. I though it I was to dive around with a scanner hooked up and the light went on then I could see what the sensors were doing when all the trouble codes fire. I was looking at the Actron CP9190, but it doesn't log the data stream for OBD1 cars, only for OBD2.

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Regal :: 2001 Buick Making Some Noise / Rough Drive

2001 Buick Regal , 125000 miles ..

A couple weeks ago I notice that my car has started making some noise and has become a rough drive. Whenever I rev, especially between 0-30 mph, its like a mini jackhammer, or a sputtering/rumbling sound when I drive.

What it could be, and what I should do?

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Buick - Regal :: 1996 - Sulfur Smell - Rough Idle?

I own a 1996 Buick Regal with 132k miles on it, 3.1L six cylinder. The other day I was doing some general maintenance and noticed that the exhaust smelled like sulfur (rotten eggs). Now, I am loosely familiar with the causes of such a thing but not well enough to diagnose it properly the first time. The car has been idling rough since I got it (almost a year ago now), I have a feeling that it could be the O2 sensor causing the rough idle and the sulfur smell but I am not completely sure. I should have one of those fancy three-part injector cleaners done?

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Regal :: Buick 1995 Shuddering / Rough Idle And Lack Of Response When Accelerate

I have a 95 Buick Regal, V6 3.8 Liter. The symptoms are the following: stuttering idle. And lack of response at times when I try to accelerate. Like sometimes I'll be driving on the highway, and having no problems. Then I'll be going up a hill at around 55 mph, and then the car will shudder as I try to maintain a speed of 55 mph. So I have to ease off the accelerator and slow down. At first I thought this was a transmission problem, but I am guessing it's the same problem that causes my choppy idle.

So I had this acceleration problem on the highway when I was going up a hill. And a weak idle. These problems have been going on for several months now. They were annoying, but didn't seem that serious. Then all of a sudden, on a rainy day, the car was really responding poorly to acceleration at all speeds. I was able to drive around, but I couldn't count on the car responding right away when I hit the gas pedal. And the car would shudder at times. Then, I didn't drive the car for a few days, and then it was dry, no rain, and the car ran better. So I am thinking humidity makes the problem worse.

I have also noticed over the past few months, that the car runs best when I start it up after a few days of not running it. Then if I drive the car a few miles and let it sit for about 2 hours or so, it would idle weakly when I would start it up again. The car's been doing that for several months now, but it wasn't really affecting the drivability or the response of the car when I hit the gas pedal.

Now it's gotten much worse. So, I've already replaced the following items myself to no avail: mass air flow sensor, oxygen sensor, and egr valve. I am guessing the next thing to fix is the pcv valve. But I also think it might be the fuel pump. My first guess though is the pcv valve. What else could it be? And is there any easy way to test to see if the fuel pump is going bad? Or should I just take out the pcv valve and see if it looks bad?

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Buick - Regal :: Rough Idle / Misfire On Cold Start - Leaking Fuel Injector(s)

1991 Buick Regal, 3800 V6

Having a rough idle on a cold start. After some research and closer inspection of the vehicle, I'm quite certain I have at least one leaking injector that is flooding a cylinder and causing the car to misfire on a cold start. I'm also not at the gas mileage I should be at.

So I'm wondering, is fuel injector replacement as straightforward of a job as it looks? Any major issues I could run into in doing a replacement?

I'm planning on replacing all six injectors (I can get them for $50 each buying online with a discount code), but given that the vehicle is so old am I better off just replacing the faulty ones? I'm assuming pulling the spark plugs and seeing which cylinder is wet will tell me which I need to replace.

And one more question: Is there a way to depressurize the fuel system when I park the car for the night, thus preventing fuel (or most of it) from leaking into the engine until I get this fixed? I've read that just unscrewing the gas cap can depressurize the system.

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Buick Century :: 1995 - Idles Rough Occasionally When Warmed Up

I have a 1995 Buick Century with 149,000 miles that will occasional and randomly idle rough when started warm. Also, on several occasions it will idle so rough it kills the engine and I'm unable to start the engine until the thermostat reads completely cold. I've taken it to 2 separate mechanics who both are unable to pull any error codes (even after the engine has died) and are unable to duplicate the problem. When it does idle rough most of the time I can rev the engine, put it in gear and drive it for a few minutes and the problem disappears. Other times I try to put it into gear and it kills, I put it into park and try to restart the engine and the engine will start for a brief second and then die and will die faster each time I restart until the engine doesn't turn over at all. Then once the thermostat reaches 'C' it starts up like there was no problem at all.

Here is a list of recent pertinent repairs:

- Replaced Battery 12/2/11
- Replaced plugs and wires 4/11/12
- Throttle Body Gasket and Fuel Filter Replaced 3/18/13
- PCV Hose replaced 2/19/14 (last mechanic's guess on the problem)

I don't notice any signs of a rich fuel mixture or abnormal exhaust (there was a discussion with a Buick with no start that had this).

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Regal :: 1995 Buick Not Cranking Over?

About the Car: It has 101,00 miles on it. I haven't own this car for long (less than a month). I bought it pretty cheap to do some grocery shopping with. I have no plans to drive it more than 10 miles in a trip. I have a bicycle with a trailer, but there are days in the winter when the weather says, "No" to bicycling. I had the fuel pump and filter replaced at a shop when it wouldn't start a couple weeks ago. They said the fuel pressure was low, and it needed to be replaced. It was fine for a little while, but then it wouldn't start for the past three days now. No cranking at all. I can turn on the radio and roll windows up and down, though. I do remember seeing a Check Engine, Battery symbol sign, and a couple other lights off-hand. I'm at work right now.. so I'll have to go home to see if the Security light also was there, too.

Also! I did find an electrical line that did not go anywhere... not sure if that has anything to do with the fact that there is no window washer fluid tank (wipers do work).

After reading a little about other Buicks in the forum not cranking, I will definitely try the Security Light issue after I get home from work.

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Regal :: 1996 Buick V6 Overheating Really Fast

I have a Buick regal 1996 v6 3.8l . SO my car tends to over heat really fast with the reservoir still nearly full of coolant also my fans also turn on really late.. Ive came down to the conclusion that it might be the temperature sensor idk whatelse to do. Ive changed the thermostat about a month ago.

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Regal :: 99 Buick GS Has A Bad Miss At Random Times

I have a 1999 Buick Regal GS with a supercharged 3.8 liter engine and 161,000 miles. I bought the car off of my uncle and he said he would have to change plug wires every month to month and a half because it would start missing so bad. When I first drove the car it would quit on me at red lights and in parking lots, it only seemed to do it at low idle speeds. I live on a hill with a blacktop road and I had to give it a lot of gas just to pull the hill it was missing so bad. The plug wire had a lifetime warranty on them so I replaced them and it stopped quitting on me but I still had a bad miss at random but not as bad it would just be like hard jerks. I added sea foam fuel injection cleaner and had the fuel filter replaced. The mechanic checked the spark plugs and he said they were like new AC Delco. I also cleaned the MAF Sensor (the mechanic told me to and how) because the engine did not run steady at idle and it seemed to work that, but not the miss. Could my problem be the plug wires? They are carquest brand 7mm wires.

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Buick - Regal :: 1995 Seems To Loose Gas Pressure

My 1995 Buick Regal seems to loose gas pressure. Have had several repairs done, fuel pump, fuel pressure regulator, fuel filter and nothing seems to work. It seems that the repair shops are guessing at the problem. Sometimes it even stalls out completely but usually starts back up.

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Buick - Regal :: Bumpy Ride At Various Speeds

Here over the last week or so I've noticed my car start to have a bumpy ride around 35-42 ish mph, and around 65-70 ish mph. It feels worse probably around that 40 range, and seems to be even more pronounced during acceleration. It's not a super high frequency or anything, maybe just a couple hundred HZ. I have been driving it considerably more over the last month with my new job (around 140 miles a day, mostly highway/interstate driving). I've got an oil change/ fluids checked about 3 weeks ago or so.

2000 buick regal ls ......

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Buick - Regal :: 1991 - All Four Tires Losing Air

I just picked up a 1991 Buick Regal for a good deal, but already the repair costs to get this thing up to speed are mounting :

Right now I'm dealing with all four tires losing pressure. The 24 year old car still has its original wheels (15 inch aluminum) and I'm assuming that they are losing pressure at the seal. The tires are only about a year old and the stems look okay, so do you think I'm on the right track?

There is one strange part to all of this: The vehicle with its equipped tires is rated at 30 PSI and if I fill them to 30 they are all down about five pounds within a few hours or after a drive. However, they do not lose more than or much more than 5 PSI. The front tires lose more air and lose it faster, but the lowest I've seen them is 23. Is only losing a few pounds of air and not going flat evidence of a seal leak or am I in the twilight zone?

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Buick - Regal :: 2001 - Odometer Lights Are Out

I have a 2001 buick regal with the odometer lights out. How do I fix this? Do I have to take the dash off to get to the light?

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Buick - Regal :: 2000 - Have No Heat - Diagnoses?

I have a 2000 Regal LS that has no heat. The cooling system is full of water. The heater hoses are warm. The fan blow lots of air and the speeds can be changed by the heater controls. The heater controls light up and you can change the fan speeds. My guess is the control doors are not working. What should I check to figure out what is wrong.

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Buick - Regal :: 1995 - AC Not Working / Getting No Spark?

my 1995 buick regal does not have a spark, and I have had 2 mechanics look at it. The sereptine belt broke while I was driving, I believe it was because the water pump was bad and locked up. the belt got wrapped up in the crank pulley and I removed it. The AC has not worked in a really long time so I do not think that it is that pulley. It is not getting a spark. I have replaced the water pump, and the car sounds like it wants to start but it is getting no spark to it. I have had the crank sensor tested and the coil something. none of those seems to be the problem. some one suggested that it is the computer brain. I suggested that it was the timing. Though I do not really know. the battery is good so i know it is not that. and it has fuel. and i know that the engine is getting fuel. I know that the spark plugs are not getting spark (tested with a screwdriver in the socket on metal) So what is wrong with it.

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Buick - Regal :: 1995 V6 Won't Start When Hot After 3rd Or 4th Stop

1995 Buick Regal, 128k miles, 3.8L V-6.Problem: When running errands around town, car will temporarily not start after 3rd or 4th stop. Vehicle cranks, has spark, has fuel pressure at fuel manifold. No codes on computer (Wish it was a '96). Car will start normally after cooling off (generally takes at least 45 minutes). No problem driving to work, parking all day, driving home. Have not tried long distance driving since problem arose, due to concern about being stuck for awhile far from home. Have determined at EGR valve is NOT a part of problem.

Sample situation: Drove 5 miles to town. Shopped for 15 minutes. Drove 2 miles further with 5 minute stop. Drove another 2 miles with 5 minute stop. Drove 1 more mile and stopped for 30-40 minutes. Car would not start. Cranks strongly, has spark and fuel pressure (don't know if fuel getting to injectors). Still would not start 30 minutes later. Left car for several hours. Started promptly and ran normally on return. Weather conditions - 90 F, low humidity. Problem has been occurring for several months. No computer codes to dive guidance.

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Buick - Regal :: 2001 - Have No Dash Lights?

My Regal has no dash lights, I checked the 7.5 amp fuse inside car and it is good.

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