Yes, please follow other directives in response to your original post.

Imagine a budget of around 1500$ in parts and some hundreds of hours of work. Unless you can't perform all work so it operates safely and reliably, with low emissions, good fuel economy, and good performance.

I like the golden or champagne color on Volvo 240s. Though I'm more of a grey, silver, or blue Volvo color guy.

Yes, a hole in the header pipe, or a leak at any union before the catalytic converter, if the 02 sensor still operates well, upsets the balance between 02 air mass intake and extant 02 measured by the 02 sensor in the catalytic converter. A large hole anywhere upstream of the 02 sensor as you describe, with a reasonably well 02 sensor, sets the fuel to air ratio to max rich.

Such a hole, as you describe, indicates a corrosion failure along entire header pipe. Bad corrosion of the steel material can mean eventual structural failure of this exhaust pipe. Best to replace it, eventually. Pay mind to the seal between the exhaust manifold (or exhaust port, on fuel injected engines) output to the header pipe input. The three, usually 15 mm nuts (use six point hex socket), can loosen over time, causing an exhaust leak, and can induce gasket failure.

At the end of the header pipe, just upstream of the header pipe output to the catalytic converter input, there should be mechanical connection to a bracket assembly secured to the exhaust side of the bell housing to redblock engine bolts. This support carries the exhaust system run weight to the front rubber hangars of the front resonator, unless you have a hacked exhaust system.

Also, you should have the spin gasket assembly on that 1993 240 wagon. This union secures the header pipe output to the catalytic converter input. At the end of each pipe is a triangular-like piece of carbon plate steel. Usually, on the catalytic converter input side, are three stud bolts that point forward, meet with the holes on the triangular-like piece of carbon plate steel on the header pipe output. This union carrier far greater stresses than the design allows.

If the catalytic converter is in fine fettle, you can use a press or ask an auto machinist to press these feeble studs out. You then use quality steel hardware of a heavier gauge for high temperature applications. I'm not sure what kind of steel. Probably not a stainless. I forget.

I'll guess you have a Volvo 240 service manual? Bentley Volvo 240 Service manual bible may be best.

As you have a OBD-1, please, now, use the OBD-1 to check for fault codes. You'll get fault codes for lean or rich running, and probably others that deal with fuel control and fuel trim with exhaust and possible vacuum leaks. Be mindful of the preheat flap valve in the air filter box. If your state vehicle emissions (and safety inspection) do not visually inspect emission controls, remove the silver foil pipe, and runs under the fan shroud, that connects the exhaust port heat shield with the air filter. Else, the AMM/MAF cooks an fails in summer time heat (and even winter time if the engine is at operating temp.

The emission controls Bosch co-developed with Volvo, before all other auto manufactures, including all German auto makers, means emission control and performance and fuel economy and low emissions are wholly integral.

You'll want a whole sale of fluid inspections and replacement. The single most important thing you can do with moving vehicle is to stop it. So, how is the break fluid? Black, I'll bet. The Motiv or other brake fluid pressure bleeder is best. Or gravity bleed. Using the brake pedal to pump fluid out is utter folly.

You have the first year of the L-block on that final year of the Volvo 240. If the engine is original to the 1993 240 golden Volvo wagon you have, you have the t-belt roller round tooth sprockets. The timing belt is rated for 100k miles as is the tensioner pulley. Contitech (OEM belts on Volvo) makes a kit with the INA tensioner.

There is so much more.

So, to help you, from the Volvo 700/900/90 FAQ, hosted right here on your brickboard.com https://www.brickboard.com/FAQ/700-900/

Review articles on Buy Used, Keeping it Rolling ... well, just review the entire FAQ and reference those articles you need now. Like OBD, sensors, and such. You would do well to search the brickboard for threads articles for issues you're dealing as you are now and will do so.

Too many 240/260 are now dead. In nearly all instances, unless from a Volvo 200-series ending crash, these Volvo automobile fail from abuse, neglect, and not driving them.

They suffer if you let them sit too long, even if they are in good shape.

Good catch on using a fuel system solvent to dissolve any fuel system plaque from the crappy ethanol in the gasoline we buy.

A stupid subsidy on a polluting scheme to make fuel from food. It makes more pollution and consumes more energy to make ethanol than any savings at the pump.

Inspect the remaining fluids, such as the aforementioned brake fluid, the transmission fluid (see FAQ and search articles), suspension bushes front and rear.

Closely inspect the strut mounts (Volvo PN 1272455). If the bushing material is pulling away from the center bearing assembly, or, if the bushing material contains concentric cracks around the center bearing assembly, replace these strut mounts with Volvo OEM ONLY. (We can't buy made in Germany Boge, who is the OEM for Volvo, until made in China overtakes the entire Volvo parts catalogue.) Do the same for the ball joints. You have some quality after market ball joints options. And the list goes on.

You have some manner of service records, yes, I hope?

Questions?

Hope that helps you begin your second 1993 Volvo 240 resurrection.
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