scrapbook said:
push hard there is no responce to the peddle and it is slugish on hills to
respond to more gas, any thoughts ?
Hi,
Hard to guess just from that description, but I'd start with the simple
things first:
Does the problem occur w/ all brands of gas? Sometimes the simplest fix
is to change brand/grade of fuel.
A bottle of Techron or Berryman's B-12 in the gas tank helps clean
injectors and remove gum and varnish from the entire system. Some would
recommend taking this step first, before changing a fuel filter as
mentioned below, to avoid clogging a new filter w/ old goo, especially
if a car's sat idle for some time.
If you have SPFI (throttle body injection), a can of aerosol cleaner
shot into the intake area can help.
--New fuel filter (Subaru OEM has worked and lasted better for me than
aftermarket)
--Air filter
--Spark plugs (if you know how to read the plugs, you may see some
clues. If not, many auto parts stores and repair manuals have a page
showing common problems to help you)
--Timing
--Spark plug wires (if you have the specs, you can test w/ ohmmeter for
resistance. Also, you can open the hood w/ engine running in the dark
and look for arcing.
--Distributor cap and rotor (if you replace plug wires, I'd definitely
let 'em have a new cap and rotor "just cuz!")
Moving up in complexity:
Check for any codes being stored by the ECU to see if any sensors are or
have been problematic in the past and threw a code.
Disconnect each of the various underhood electrical connectors (engine
off, battery ground strap disconnected), clean w/ aerosol cleaner (get
the stuff for electronic/electrical equipment--better auto parts stores
stock it), then reconnect using a bit of dielectric grease on the
contacts in the connector (again, better auto parts store) to reduce
future corrosion. (Do NOT use dielectric grease on the connector for the
O2 sensor, though. I've seen articles stating certain O2 sensors can be
damaged doing this.)
O2 sensor (if you don't mind splicing the feed wire, aftermarket is 1/4
to 1/3 the price of my dealer's OEM, and works as well for me.) Newer
models will throw a code w/ a bad O2 sensor. My '90 Loyale doesn't, and
I doubt your '91 will, either.
Fuel pump pressure low. You may need a pro to test that.
Oddball possibilities:
Incorrect t-stat temperature, "confuses" the ECU into thinking the
engine's not warmed up, runs rich. Use Subaru OEM t-stat.
Timing belt incorrectly installed, with valve timing affected
negatively.
Compression test if none of the above help: sick cylinder(s)? A skillful
reader of a compression tester may also be able to diagnose a timing
belt problem this way without having to unbutton the front of the
engine--I personally can't.
Really oddball possibility:
If the car's an automatic, is the trans full of clean fluid and not
slipping? If it's a stick, is the clutch disengaging fully and not
slipping? Your post says "no responce" to additional pedal force, so I
assume you mean the engine itself doesn't respond, as opposed to the
engine responding and the car not moving faster? If that's the case, the
trans/clutch suggestion's off the screen.
Good luck,
Rick
