I have a 88 ranger 2.0 carbureted 5 speed that I just bought a few weeks ago. Smog pump wasn't hooked up to a belt and it looks like a lot of stuff is jery rigged. I don't need to pass emissions so I removed it and the hoses that go from it to the engine and exhaust and routed the hose from the exhaust manifold directly to what I believe is the cat conv. pipe(runs kinda parallel with and into the exhaust near the muffler) and capped the hose that came over and joined air cleaner diverter valve from the drivers side of the engine. Lots of vacuum lines were running from defunct smog pump to air cleaner etc.

Everyone tells me I should toss all that crap but I don't know what is necessary and what can be eliminated. I would like to eliminate everything I dont need, as near to bare bones as possible. Vacuum diagram is hard to understand and isnt much help because alot of stuff was doing nothing and or missing.

I should say that the truck runs decent in general. Pulls good in 1st, 2nd, and 3rd, but is kinda weak in 4th and has a top speed of about 55-60 with no real response in 5th(overdrive).

I know its an old 2.0 but don't get why it runs good in lower gears but just blah at highway speeds.

Please help.

 

Exhaust could be getting clogged up which effects power at highway speeds, back pressure increase so new fuel can't be pulled in.
Vacuum gauge can tell if that is happening.

Dirty Fuel filter also can limit fuel replacement at high speeds so no power.
Replacing fuel filter on "new" old vehicle is always a good idea.

Google: autozone 1988 ranger vacuum

Autozone has a good repair site with vacuum and wiring diagrams.

Look for a vacuum diagram for a 2.0 or 2.3 that didn't come with smog pump.

The smog system on some engines helped to prevent "pinging", so after removal if you start to get 'pinging" on acceleration you may have to reset the spark timing or run higher octane gas.
EGR system does not "take" power, it helps keep the cylinders cooler under load, this lowers the emissions, but also helps prevent "pinging"

 

Ron D,
Thanks for the help. Fuel filter was in fact leaking slightly, replaced it. Tried some 89 gas and I couldnt say if it was that, the fuel filter, or the badly needed oil change; but slight improvements on the highway en route to a used bed liner. Turns out one of the "useless" hoses my buddy and I cut and plugged was coming off the pcv valve. Was advised to unplug it and rout it into the oil filler/breather cap. Got a line on a header from a 96 model 2.3. Was told that might add a little power and possibly fuel economy. So many experts, so little money..