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Bogging out after a couple of hours driving

772 Views 7 Replies 4 Participants Last post by  Gabriel661
I have a 1990 Cadillac Brougham the car runs good, starts up find does not shake at idle it does smoke quite a bit and I know it's burning oil but overall it drives pretty normal
But after driving it for a couple of hours around town it starts feeling like it's bogging out at take offs once I get to a higher speed it goes away but as soon as I stopped at a stoplight You can feel a slight jerk it's not that bad you can barely feel it when you take off. Could it be something to do with the carburetor I know it can use a rebuilt my friend told me that it could be the EGR valve is plugging due to the fact that the car smokes quite a bit so my question is could this be a carburetor problem or is it something else. The bad thing about these carburetors is that nobody in my town knows how to work on them are rebuild them anymore if somebody can please give me some advice it would be greatly appreciated thanks
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Its a 5.0
We need to know if it's a 5.0 or a 5.7 car. From your post, I'll guess 5.0, but need to make sure.
Try looking for a vacuum leak as that could be part of your problem.

Yes, many many sources of vacuum leaks, and not even half are related all the hoses around the engine. Look also to old worn electrical components of the ignition system getting weak from increased resistance from heat-soak. Also run down whether your year used the Q-Jet that had the famous 'leaking jet plugs'. If so, there's bound to be many YouTubes on it by now.

You didn't list the mileage, how long you've owned it, nor your general appetite or tolerance in doing basic maint. work yourself. Rebuild kits are available for most production carbs, and really aren't that complex with patience and basic handtools. It's surprising how much a replacement rubber accelerator pump in the carb can improve responsiveness. You've got a nice old 30-year old ride. Invest your time and some $$$ showing it respect by making every excuse to pulling some serious periodic maint. on the ignition, fuel and air delivery system components. Ign. Coil, IC module, plugs, wires, cap/rotor if your motor has them. fuel filter, carb rebuild. Fuel pumps wear out too. There's simple checks for pressure using a loaned gauge from most part houses. I'd buy 5' of every size vacuum hose under the hood and just replace them all. Attack the emissions system too. It causes lots of degraded operation when not kept up. Simple stuff like PCV valve. Canister purge solenoid and valve. The EGR is a perfect periodic maint. item. There's a simple way to check whether it's clogged or a broke diaphragm. I'd simply not talk about it anymore and just replace it if it's more than 15 years old. The additive effects of properly operating parts of one system have surprising additive benefits on seemingly unrelated other systems. Don't even stop for a beer until you've spent at least $300 for parts. Probably 3-4x that if you go to a shop. Without substantially more diagnosis and background that would be my advice.

Give a pic of the old girl when you get a chance.
The car has 74000 original miles on it. I just get it 8 months ago. The previous owner told me that he didn't Drive it much in the past 10 years he's only put 4000 miles on it. I recently changed the oil , new radiator alternator valve cover gasket, belts. The carburetor is a 4 barrel Q-jet. I tried to do most of the work myself Not just to save me some money but to learn how to work on my own ride. I recently put a hydraulic suspension set up on it. It's not a daily driver is just a weekend cruiser


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The car is making this sound when I accelerate
Click on the link I have a video of what it sounds like pinging
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