Buick - Regal :: Rough Idle / Misfire On Cold Start - Leaking Fuel Injector(s)
Sep 7, 2014
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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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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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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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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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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1991 Buick Regal, 3800 V6
As the title says, when I start the engine cold I get a slight puttering and drop in RPMs followed by the engine revving itself to about 1100 for a few seconds and then normalizing at 600. It has only actually stalled out a few times. This does not happen once the engine is near operating temperature.
Now, I did not notice this issue prior to doing some maintenance on the vehicle (radiator replacement and transmission service) and I've read that this can be caused by a faulty coolant sensor. Possible?
Battery is new.
Also, when I say cold start I mean summer temps here in Michigan. So it's happening anywhere from 50 to 90 degrees F.
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I have an '88 EXP Escort with the non-HO 1.9L
I was noticing a rough idle (vibrating, sounded like it was bogging down)
I changed the plugs, wires, cap and rotor. Still happening.
Noticed that my o2 sensor was unplugged. Plugged it back in. Still happening.
Went to check the air filter and noticed the insane amount of fuel that was coming from my injector.
I am getting horrible gas mileage (8-12mpg)
Here is a video of what I am seeing: [URL] ....
What would be causing that much fuel to be sent out?
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My new 2015 Sonata 2.0Twith 8000 miles started running oddly about 2 weeks ago. Rough idle with engine "sputtering". Erratic acceleration -- merging into traffic on highway and car not going over 40mph, even with gas pedal all the way to the floor. On deceleration, clunky down-shifting. Very hard to drive. Dealership first came back with diagnosis of "buildup on throttle plate" (Note - I use only high-quality gas AND only have 8000 miles on car, 3500 or that being one long highway road trip). Then, after 3 days of diagnosis, they say I need 2 new fuel injectors I am baffled how a new car can have either buildup or failed fuel injectors...
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I have a hard starting condition after warm up. It starts up fine when it is cold.After running diagnostics and coming up with no error codes, I noticed that I smell raw fuel after the car was warmed up and sitting for about 15 minutes. I believe this is the cause of the hard starting condition after warm up.
How do I test the fuel injector for leaking? I think it may be leaking fuel into the throttle body after sitting for a few minutes, causing a rich or flooded condition which makes it difficult to start after it has been warmed up.
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Truck is a completely stock 2002. New injector o-rings, glow plugs, valve cover harness, and injector cups a year ago... all motorcraft parts. New batteries and starter in the last 6 months.
I've checked the GPR both at the relay and harness got power all the way to the valve cover harness on all 8. Injector buzz test sounds okay as well.
Had a stuck IPR issue a few moths ago that caused a CEL and died while running. Took apart and cleaned the IPR and CEL is gone truck runs great once started and has correct IPR pressures in all RPM ranges.
Truck runs great once it is started and is not sluggish until warm like when it was hard to start when cold with leaking injector o-rings.
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My son is about to purchase his first car. A 98 Buick Park Regal. Feels like it idles rough, and has a little hang-up when it shifts. Seller claims it's due to needing a transmission mount replaced. Does this sound viable?
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2012 F-150 5.0 Rough Idle Upon Start up - YouTube
Whenever I first start my 2012 F-150 with the 5.0, it idles rough and if I step on the gas it acts like either an injector is cutting in and out or it's missing. It doesn't really seem like a miss though, more like an injector/fuel issue. What it could be. If I let it sit and idle it won't go away unless I step on the gas and get it > 2500rpm or so.
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Ok, my 1996 Buick Regal is acting up. I got a CEL, which was a P0306 (Cylinder #6 misfire), took the car to my shop, and they diagnosed as a faulty Ignition Control Module. Fast Forward, a day later, the car now has a hard start problem and throwing the same code, plus a P0102 Mass Airflow Sensor.
So my questions are:
1) Could a faulty ICM cause a single cylinder misfire, did they just replaced a random part? I would think a bad ICM would a multiple misfire considering on this car each coil controls 2 cylinders.
2) Are the two codes related? ie fix one, and the other would go away? or are they separate issues?
3) What could be wrong with my car?
This mechanic has been in my family for years, however, I'm not very pleased that a day later, my car seems to have more problems than before. Am I being too harsh?
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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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My moms has a 2010 Elantra with 30,000kms on the clock, and we have noticed since new when the vehicle is started cold in the morning it seems to run rough for about 30-60 seconds then stabilizes.
It's almost like it has a slight misfire, or slight fuel flooded from sitting overnight. Now if course we have taken it to the dealership twice for this issue and dropped it off overnight for a cold start, and both times they cannot re-produce the problem.......surprise.
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I have a 98 Buick Regal. When my air conditioning works, it is beautiful. On a hot and sunny day when I pull out of the garage, I can run the air conditioning until the car is turned off. After reaching a destination and parking in the hot sun the compressor will not blow cold air. If the day is overcast or cool, the air conditioning works fine. What the problem might be?
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The equipment:1995 Buick Regal Custom 3.8
I noticed a year ago that my car would randomly stall out coming into work after a 20-25 minute drive. It then started to idle really high, very rarely. So i cleaned the throtle body, new air filter, new fuel filter, sparks, and wires. This is about where my expertise ends.
Its seemed better, however, it would act up now and again (stall) but I was fine with it.
Recently I have noticed that the car idles really high 1.5 in drive (compared to 900) and 2k in park after I have drove for 20-25 mins. So I put the computer to the car and all I have is transmission error codes which I have had since I owned the car at 80,000 miles and I am now to 160,000 miles. This car has been pretty good to me because it starts, goes forward, and backwards! What else can you really ask for. A better idle maybe?
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2001 Buick Regal with approx 250,000 miles. 3.8L V6. Non supercharged It's my son's car. Used to be mine, I bought it with 19,000 on the clock.
The battery succumbed to the cold weather last Monday. On Tuesday, I put a new battery in, which itself now works fine. However, since then, the car refused to idle decently. It'll idle right after startup, but once you put it in gear, it'll die. When you start it, it seems to idle normally, you can let it warm up a bit and it'll settle down to about 900 rpm. BUT! Once you put it in gear, it'll stumble and die.
This problem started after battery replacement, so I have to wonder if it's somehow related to that. It ran fine before the battery died. I checked everything over thoroughly, and visually everything looks OK. No loose wires or hoses, etc.;
Today is the first time I've had to work on it since the new battery, so I thought I'd get it out there. I'm getting ready to go put a scan tool on it and will report back with those results.
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I now have an annoying "clatter" sound coming from my supercharger cone housing ONLY when the car is in gear and at idle (i.e.,: stop light,etc.).. Had a new serpentine belt replaced 6 months ago with new water pump.114K miles, great condition otherwise.
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When damp or foggy, my 1990 Buick Century 3.3 will either not start or start and idle rough. Spraying WD-40 on coil packs and wires work. I tried click and clack's method of misting water on the 3 coil packs and wires when idling, and got arching on middle coil, # 2 wire to top of coil pack. Do I need to replace that coil, or just the spark plug wires? The slight mist of water on that middle coil stalled the engine, and it would restart after WD- 40 was sprayed on the coils/ wires.
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[URL] I even pulled the same P0170 code. And what I need to do before I spend a boatload of money and wind up sleeping in my car instead of driving it to work or lack therof is to start a troubleshooting list starting from where Sabot's update left off, i dont even know where the vacuum line is that he mentions and if i sprayed carb cleaner on it would i get a jump in engine RPM or a stall as a test?
What I have done: Cleaned MAF sensor, changed fuel filter.
What I have not done: Checked all vacuum lines, Tested fuel pressure, Tested for compression issues due to blown head gasket.
there is also a puffing noise coming from the exhaust side of the engine, im gonna grab a bottle of baby powder this afternoon and test for air leaks, i dont believe it is a misfire...
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