How to get trouble codes buick regal 1984

From what I have been able to find, I would check your EGR (exhaust gas recirculation) valve. Since you are getting a code I would think it would be electronic. Older engines used vacuum ones.

Good luck

information found here

P0404 Exhaust Gas Recirculation Circuit Range Performance

Possibly you could tell us what parts you replaced ? , possibly you could tell us if the check engine light is on?. what are the codes when you read them out ? The computer does not tell you what part to replace,, but tells you what part of the system is failing.. you have to figure out which part is causing the problem.What state do you live in? By the way.. The DMV will not stop you from driving the car.. you would just have to pay the ticket if you are stopped and a ticket issued. Post a comment and give us these answers for more help..

The emissions control valve is bad. Get a manual for your car from an auto parts store for the location and removal instructions.

Just under the dash on the driver's side. GM always put them there, I think. They usually stuck out just a little from the very lowest panel on the dash. Post back if you need the code retrieval process and/or code descriptions, and I can give you a link. Or, what the hey, here it is:

Take it to autozone or another place like it and have them read the codes and tell us what they are.

sometimes is hard to get there and cost a lot of money.

You need a specific adapter to scan your trouble codes. Vehicles prior to 1996 use OBD1 scanners, which are very expensive. Your best bet is to call around a few shops in your area and ask what they would charge to diagnose the code. It sounds like you may have more than 1 problem. The emissions could be due to a bad oxygen sensor and acceleration problem may be due to bad plugs, plug wires, clogged fuel filter, rotor and distributor cap, etc. Do a tune up on it, then see where you stand. At least you won't have to pay a shop to do it if that fixes your acceleration problem.

Sounds like a bad wiring connection in the egr circuit.

you need to find someone with an old type scan tool,or one that has an adapter for the older cars to read the codes. you can also do this by jumping 2 wires on tha obd connector and count the flashes. the first suggestion is the best. get the code and get back to me and we'll go from there. hope this helps Thanks Ray

the light is flashing to tell u that the engione has one or more engine cylinders misfiring, have the trouble codes tested to find out which cylinder(ws) is he problem.