Lacks acceleration and has a strong odor of gas while driving

Well, at 148,000 there are several things that could be the problem.

Is the service engine light coming on? If so, you can actually get the codes from the computer with a simple process using a paper clip or jumper wire. Here is a guide for that: https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Personally, if it has not been tuned up for a while, I would check the condition of the spark plugs. Weak plugs can cause loss of power, loss of fuel economy (not that you had much to begin with in that car), and that odor of gas. So here is a spark plug how-to guide: https://www.2carpros.com/articles/how-to-change-spark-plugs

Also, look to see what brand the plugs are. Write down any identifying information so we can see whether or not those plugs actually belong in that car.

It could also be a very clogged air filter. Here is a general guide on that: https://www.2carpros.com/articles/how-to-replace-a-car-air-filter

Also, look at the condition of the vacuum lines. Of course, we have a guide for that too: https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Check these things and let us know what you find.

Thank you for your response,I have performed basic tuneup of oil,oil filter,fuel filter,spark plugs,pcv,and replaced 1 broken vacuum line.new alternator and battery.new brake pads and rotors.cleaned egr and tube.there is no check engine light on and no codes faulty in obd.I was unable to find ac delco plugs so replaced with autolite spark plugs.check all vacuum lines no leakd detected.any additional help is appreciated.

What about the plug wires, distributor cap, and rotor? New plugs will not make a bit of difference if the sparks coming from the distributor and through the wires is weak.

No have not changed wires rotor and cap because previous owner had said he had changed them before car was sold, but I guess I should replace and see what happens. is it true I should only use ACdelco spark plugs in the Northstar engine? if so I need to change out new plugs they are Autolites. if you have anymore information it is greatly appreciated.Thank you

Well that's not a northstar, but yes you should generally use OEM ignition parts. The reason being, with those cars, they seem to wear out lower quality plugs and wires quickly. I can't put my finger on why, but I suspect it has something to do with the high and hot spark strength. Personally, I order my parts either from RockAuto.com or Amazon using my wife's Prime account. You can save quite a bit of money ordering online.

Also, I seem to remember that those 4.1, 4.5, and 4.9L Cadillacs very specifically call for premium gas only. These days, that means you really should only use premium gas and get it from major brand stations like BP/Amoco and Shell. Yes, it makes a huge difference in these cars because octane gas will preignite, meaning it starts burning before the spark plug fires and causes power loss.

Cool,Thank you for your help. I will order plug wires rotor and cap from amazon they have better pricing just have to wait for delivery,but worth it if it helps.when I install em I'll give you an update.appreciate it much. Thanks.Happy Holidays.Have a Good one.

Hello, just wanted to give an update on earlier post.I ordered and received the new spark plugs, wires dist. Cap and rotor.upon removing old cap I noticed the inside plastic where rotor brush inserts was broken and there was no brush attached to the spring was only contacting by thin spring.anyway replaced cap rotor brush and gasket.big improvement.new spark plugs and wires seems to help immensely.the smell of the fuel looks like it's coming from throttle body gasket ordered new kit.but temporarily sealed it with gasket maker.seems to work pretty good.but finding the further I get into the engine the more problems I find,suppose thats a good thing before they turn major.just wanted to thank you for all your help you are a lifesaver.best wishes and Happy Hollidays.

Hey I'm glad to read that you seem to have gotten to the bottom of the problem. That's exactly what we like to see on this site. Please do update us again when you get that throttle body gasket.

Hello Heyman.update to fuel smell in engine compartment.I found the throttle body gasket was cracked ordered new throttle body gasket kit, installed and it seems to have done the trick.no nore fuel smell.again big thanks for all your help.and thank you for this website.currently trying to find out how to test the air ride system, after turning on car and letting it idle the info screen shows a green lit car is leveling but doesn't seem to do anything.noticed the inner part of the rear tires have severe wear.tires are less than 2 yrs. Old. Could this be do to a faulty airride system?any help is appreciated.

Hey I'm glad we could help! As for the air ride system, I'm not much of a help when it comes to suspension stuff. But I believe that if the air shocks are leaking, then the rear end is kind of squatting down a bit, which can throw off the camber of the rear wheels, putting a lot of extra wear on the tires. If I were you, I'd start a new thread on that and hopefully one of the other experts who knows more about suspensions can help.

Again, I'm glad to read that you got it running better.