1990 240DL OBD 231, 232 & 221 poor fuel economy

[lummert]

I'm curious about this "1999 240DL".

[93Regina]

I don't want to do wholesale part swaps in a shotgun approach...

Ah yes, "no pain, no gain;" otherwise experience the thrill of breakdowns on the road ahead Do remember, its the engines that can last a long time in a Volvo, not the electronics.

When I get an used vehicle, it sits in the shop while I pitch about $1K in parts before I drive it; interestingly, breakdowns become history, mostly.

So, we have the LH 2.4 codes, where are the EZK 116 codes?

Myself, I'd replace the O2 sensor, and the CPS (RPM)...

[93Regina]

It's more of a don't replace it unless it's broken approach...

Oh, the old "penny wise, pound foolish" approach; those over the road repairs, are not only a PIA, but sometimes, can cost several times over, when compared to doing it yourself at home.

Older FPR...a no brainer, replace it with a Bosch
Older CPS...
Older fuel/ignition relay...
Repack/Replace front wheel bearings and seals...
Check Drive-Line and Trans/Rear-End
Check Air Filter
Renew Timing Belt and pulley

and the list goes on...either you want a vehicle to use, or a local puddle-jumper having break-downs.

Hey, I drove out to Oregon, over several mountain passes, a 1982 Caprice in 2001; and while stopped, someone asked, "you drove that from Kansas?" Sure did, but before the trip...water pump, fan clutch, new radiator, fuel pump...and I drove it back also.

[93Regina]

EZK 116 codes 111

Engine and OBD Diagnostic Codes

With all of those fuel codes, either something is amiss with an injector(s), or something else is causing the issue (AMM, CPS, etc).

Resealing the injectors is fine, but I went on ebay and bought a set of Bosch 0 280 155 746 Injectors, which are a Bosch Type III design. If not doing mostly highway driving, one won't see a slight increase in fuel economy. If injectors sit too long, they can fail when installed. I had mine cleaned/tested, and then I installed them.

Bosch Regulator - All it means is that it should be to Bosch's standards. I suspect any valid name (BorgWarner, etc) would suffice, but made in China by WongKu may be crap.