No engine power


  #1  
Old 04-15-04, 02:39 AM
Dvdj43
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No engine power

Have an '86 Buick Regal, 307 w/4brl Rochester. Car starts & idles easy. No power on acceleration, engine chokes unless I rapidly pump accelerator pedal.

Engine will choke at any speed and at any temperature. Does not stall when at idle.

Have checked that fuel is injected into carb. Checked filters, spark plugs, dist. wires & cap, all seem normal, no defects at all. Timing seems to be fine, when adjusted, it made little difference.

Engine surges and some times backfires out the carb. Vaccuum lines seem to be intact and free of leaks. At some point before I owned the car the Thermostatic Choke was worked on and the setting was off. I tried to adjust this and it made little difference.

I am at my wits end, the car is in beautiful condition with over 100,000.0 miles. It was given to me by a friend and he stated that this problem suddenly occurred. HELP !
 
  #2  
Old 04-15-04, 03:39 AM
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could be alot of things that may cause your problem have you gotten the vehicle to die completly under acceleration if so how does it restart does it start right back up, or does it crank over excessivly long before restarting?
things to check would be fuel pressure, possible carb problem, or even an ignition system problem such as a very weak coil, even checking the exhaust system for a restriction.
might want to have a shop diagnoss the problem if you dont have the equipment to narrow down which system the problem is at, such as ignition system, fuel system.
if the carb is still sealed at the air mixture screws you can pretty much expect that it is due for a rebuild.
 
  #3  
Old 04-15-04, 03:49 AM
Dvdj43
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Thanks Bejay for your reply, yes I have stalled it on acceleration and it starts right back up. However there is something I forgot to mention earlier and that is the engine will make a deep gurggling sound at low idle. The sound reminds me of an extremely powerful, high-performance engine. If I tap the accelerator this sound goes away and the engine sounds and idles smoothly.
 
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Old 04-15-04, 04:16 AM
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not sure that the noise would be associated with the problems your having may just be hearing part of the smog system, especially, if it was when the air cleaner was off as the air pump would of been diverting air to your air cleaner which would make this noise really noticable when it isnt muffled by the air cleaner housing.
if you can get the vehicile to bog down while the car isnt moving you can usually spray a small amount of carb cleaner down the carb while the engine is choking out, if the engine immediatly picks up you will know it is a fuel system problem and the engine is not getting enough fuel, suspect internal carb problem or possibly a fuel pump, also good idea to have a fire extinguisher handy when doing this as if the vehicle was to back fire it could easily start a fire, if the engine still chokes out or condition doesnt change you will need to look at your other areas ignition system, exhaust.
 
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Old 04-15-04, 04:47 AM
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just a thought...

...your description smacks of a bad accelerator pump in the carb. that would require an overhaul. checking fuel pressure is a good thing...but the fact that it starts back up right away tells me that the carb isn't running out of fuel. the backfiring can also be from leanness (not choking as this would indicate a severe rich condition)...which fits with a bad accelerator pump.

i'd also add that propane makes a much safer fuel supplement than carb cleaner...the test makes sense tho...it will help pinpoint a fuel problem.

the gurgling sound does sound like secondary air injection system noise...probably not an issue at this point.
 
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Old 04-15-04, 07:36 AM
Dvdj43
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Thanks guys for the response. I guess my next plan of attack is to rebuild the carb. I am not sure what exactly comes in the kits other than "o" rings, gaskets and etc..

I will look into it. It would be faster to just install a rebuilt carb. instead ah... but I would not have the satisfaction of fixing my current carb. HA HA !
 
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Old 04-15-04, 08:10 AM
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rebuilding that carb...

...may be more challenging than you think. it's an electromechanical carb with a pile of internal and external adjustments. most of which take some special tools...you'll need guaging tools to set the float (probably comes with the kit), as well as to set the m/c solenoid (it makes a big difference if you get it off)bending tools and guages for the vacuum breaks and a bubble guage to get the choke right. i built a many of them back in the 80's (13 years in a multiline GM dealer...80-93).

you might want to review the rebuild procedures in a manual before you decide to tackle it.

ps...a rebuilt carb (reman) will also need fine tuning to have it as good as possible.

carbs were cool and all...but they are incredibly inefficient
 
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Old 04-15-04, 08:16 AM
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I am not a mechanic just fool around time to time. But this does sound a lot like a problem I once had when my catalectic converter became clogged. The converter got really hot to the point of glowing and I had no power but it would idle. It also backfired from the carb. Just thought this might help hope it does.
 
  #9  
Old 04-16-04, 03:26 AM
Dvdj43
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Well I purchased a rebuild kit and I was going to ask how daunting a task this might be. The kit I looked at, though it was not for my carb, had mostly gaskets, a few jet(?) screws, accelerator pump, and a few other small parts. There were no other parts that would require the need of bending tools. I am not sure of what I am getting into however that is usually the case with most of the repairs I have made over the years.
I am not sure what part of the carb. I should start with first, I guess I will figure it out, Oh joy! You guys have been a great help and I will keep you posted.
I was wondering what other items I may need for this such as a carb. spray cleaner, maybe some extra springs, anything else?
I don't believe I have to touch any of the external adjustment screws, do I? I will look into the possible converter problem oh and one more thing I found out that if I depress the gas pedal all the way the engine does not stall it slowly trudges along, though when cold it did stall and the car would start right up again.
 
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Old 04-16-04, 04:29 AM
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Disconnect the converter and support the exhaust with some wire.Drive the car if it has power now you know the cat is bad before buying anything.The carb requires special screwdrivers and guages to do,you will have to do external adjustments also.Try the cat test first.If you find the cat is bad then you need to find out why it went bad.
 
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Old 04-16-04, 02:20 PM
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this car should have an o2 sensor that you could remove to see if the vehicle runs better would likely be easier than unhooking the convertor, or just take it to an exhaust shop and have a backpressure test run on it they usually dont charge much to perform this test.
the only thing that you bend in rebuilding this carb is the float to adjust it that can be done by hand, and using the measure guage that is included with the kit, if you do rebuild the carb I would recomend replacing the float which does not come with a carb kit.
it does require some special tools to do correctly requires a tool to remove the jets in the carb, and the rich stop screw so you can remove the plug above the rich stop, a tps adjustment tool, double d idle mixture tool or socket for removing the idle mixture screws and adjusting the mixture afterwards, you may have to remove the plugs over the idle mixture screws to access them if it has not already been done, and on top of these tools you need to make sure that the tps and feedback solenoid are still in good working condition before even starting on rebuilding the carb, which a shop would use a scan tool to check theses components and make final adjustments on the carb. so I would suggest you take it to a shop if you do need to rebuild the carb, this is still usually cheaper than buying a remanufactured carb unless your current carb needs alot more than just a kit and float, such as mixture control solenoid, tps, choke stat, choke pull offs.
 
 

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