engine hesitation

[jfindlay]

I have a 1988 GL 1.8 SPFI 4WD wagon. In August I noticed that when the
engine started up cold sometimes it would die or if I shifted it into
neutral and let the clutch out that would be enough resistance to kill
the engine.

After learning about how the fuel system can be clogged over time and
how (and how not) to clean it I put a can of BG 44K in and an Italian
tuneup later the engine runs quite smoothly and quietly except for a
rapid (fuel injector?) tapping sound coming from the intake assembly
directly under the air intake boot.

However, something that the FI cleaner didn't remedy is that for the
1.5 years I've owned the car it has been stuttering, hesitating, and
just plain going slow on accelerations. Sometimes it can get into the
groove and run at ideal performance but mostly it feels as if it's
laboring along afflicted by some malady which impairs it's power and
perhaps fuel efficiency.

What things can I try? I've thought about disassembling the air intake
apparatus to see if anything is out of tune or swapping out the spark
plugs (which actually look fine).

 

[Joe Kultgen]

(e-mail address removed) wrote in @m73g2000cwd.googlegroups.com:

I have a 1988 GL 1.8 SPFI 4WD wagon. In August I noticed that when the
engine started up cold sometimes it would die or if I shifted it into
neutral and let the clutch out that would be enough resistance to kill
the engine.

Start by reading any stored ECU codes.

If those check out work your way through the fuel system starting with
cleaning the MAF sensor wires, (use electrical contact cleaner, don't
actually touch them.

Check operation of the IAC, TPS, EGR valve as well as the ERG and canister
purge solonoids.

If that all sounds like techno babble get to www.ultimatesubaru.org and
search for links to the Factory Service Manual (FSM) or the SPFI conversion
manual which includes relevant pages from the FSM regarding
troubleshooting the fuel injection system. A couple hours with a
multimeter can make a huge difference in how it drives.

Joe

 

[Todd H.]

I have a 1988 GL 1.8 SPFI 4WD wagon. In August I noticed that when the
engine started up cold sometimes it would die or if I shifted it into
neutral and let the clutch out that would be enough resistance to kill
the engine.

After learning about how the fuel system can be clogged over time and
how (and how not) to clean it I put a can of BG 44K in and an Italian
tuneup later the engine runs quite smoothly and quietly except for a
rapid (fuel injector?) tapping sound coming from the intake assembly
directly under the air intake boot.

However, something that the FI cleaner didn't remedy is that for the
1.5 years I've owned the car it has been stuttering, hesitating, and
just plain going slow on accelerations. Sometimes it can get into the
groove and run at ideal performance but mostly it feels as if it's
laboring along afflicted by some malady which impairs it's power and
perhaps fuel efficiency.

What things can I try? I've thought about disassembling the air intake
apparatus to see if anything is out of tune or swapping out the spark
plugs (which actually look fine).

I scored here a few weeks ago suggesting "try replacing the plug
wires, and see if the problem goes away" on a hesitation problem.

I had a mazda 626 that, especially when it was humid or raining out or
after a carwash would hesitate on acceleration, and it was always plug
wires. Not sure what it was about that engine, but about every 30k mi
it'd need new ones.

If your car has a distributor ignition, check the cap -- see if it's
cracked. A fouled distributor could give this symptom too.

YMMV. Hope it helps though!

 

[jfindlay]

I scored here a few weeks ago suggesting "try replacing the plug
wires, and see if the problem goes away" on a hesitation problem.

Unfortunately all the plugs, cables, and distributor cap and rotor have
been replaced within the last year. Ignition coil maybe?

YMMV.

Heh, literally. (-:


Justin

 

[jfindlay]

If that all sounds like techno babble get to www.ultimatesubaru.org and
search for links to the Factory Service Manual (FSM) or the SPFI conversion
manual which includes relevant pages from the FSM regarding
troubleshooting the fuel injection system. A couple hours with a
multimeter can make a huge difference in how it drives.

I've poked through the site manually and via google,

http://www.google.com/search?q=FSM+site:www.ultimatesubaru.org

which unfortunately yielded nothing. I am willing and able to probe
the electronics with a multimeter, however I'm so far ignorant as to
any sense regarding the intricate array of hoses and wires strewn
across the top of the engine. (-:


Justin

 

[Todd H.]

Unfortunately all the plugs, cables, and distributor cap and rotor have
been replaced within the last year. Ignition coil maybe?

Well poo. Then I'm no use to ya. Yeah, a coil could cause the
issue. I believe, a multimeter can be used to test it even, but i'm
not sure of the exact procedure and ranges etc.

Heh, literally. (-:

This is a pretty hip crowd, by god.

 

[Joe Kultgen]

(e-mail address removed) wrote in

I've poked through the site manually and via google,

http://www.google.com/search?q=FSM+site:www.ultimatesubaru.org

which unfortunately yielded nothing. I am willing and able to probe
the electronics with a multimeter, however I'm so far ignorant as to
any sense regarding the intricate array of hoses and wires strewn
across the top of the engine. (-:


Justin

Try these. They're for an '89 but the info should be close enough to be
helpful.


http://www.ch601.org/engines/files/SubaruEA82-ServiceManualPart1.pdf
http://www.ch601.org/engines/files/SubaruEA82-ServiceManualPart2.pdf

You may want to right click and do a "save link as", the first file is a
little over five MB and the second is a little over 3 MB. Most of the
SPFI troubleshooting info is in the second part.

Later,
Joe