still having problems with my 240

My 1990 245 still has a problem. It was running a bit rough, but
getting good mileage and had good power and response. Then one morning
it had a problem. It hesitates at throttle opening and is low on
power, but runs fair above about 2000 rpm, but still hesitates a
little when throttle is increased in that range, but responds better
than at off-idle. The off-idle peformance is really poor, and with a
cold engine I can nearly get it to die by slowly opening the throttle.
It feels to me like an overly-lean situation- no popping, backfiring,
or any such symptoms that would indicate an overly-rich state. When I
"pump" the throttle I can get it to not hesitate quiite so badly
off-idle, so it would seem, again, to point to an lean mixture (I
realize it does not have an accelerator pump).

At first I thought Throttle Position Switch, but the hesitation and
low-power is at least somewhat evident throughout the normal operating
RPM range.

I have checked a LOT of things, including (but not limited to):
-OBD socket 2 and socket 6 codes (none displayed for some time, but
originally was getting a 1-2-1, "no signal to/from AMM").
-OBD socket 2, test 2 and 3. Everything checked out fine.
-Cleaned and reinstalled throttle body
-Cleaned and reinstalled Idle Air Control (this car has the 2 wire
version
-Readjusted Throttle Position Switch (three times)
-Readjusted throttle cable and linkage
-Adjusted idle stop
-Checked for any air leaks between AMM and throttle body.
-Replaced Plugs, ignition wires, and dist cap (rotor on the way).
-Checked every vac line I could find, made sure that they were tight,
and trimmed the ends of those that felt even a little loose.
-Checked all the intake manifold bolts.
-Cleaned all vac fittings on manifold to be sure they were clear.
-Cleaned flame trap and related lines. (good vac at oil cap and no
significant oil leaks).
-Removed all under-hood connectors I could find, cleaned contacts,
silicone greased, and reconnected/disconnected a few times before
fastening.

Another oddity (maybe) is that the "Check Engine" light never came on.
It illuminates when the switch is in P-II and goes out when the cars
is started, but even when the AMM code was set, the light did not come
on... if that means anything... I hope not.

I have a few guesses as to what it might be, but to just start
replacing parts until I get lucky can get expensive, particularly with
what one or two of the suspects cost! I also have a few more things to
check, but thought I would ask here to see if I am heading in the
right direction before I give up and take it to an independent service
center..

I am going to try the "Spray something on all vac leak suspected
places to see if the RPM or behavior changes" trick (use WD-40?), but
if you have any thoughts or any directions to send me beyond all this
please feel free to share them. I would much rather be driving my car
than washing my hands three or four times a day with mechanics' hand
cleaner, if you know what I mean..

It is (or seems to be) idling a bit smoother (roughness mostly gone, I
think) but the hesitation is fairly severe and needs to be taken care
of.

When started cold, it goes to about 2000 RPM, drops to about 700-800
or so, goes back up to about 1100, then settles in at around 1000,
slowly dropping to around the correct idle speed as it warms up.

HELP!

.... and thanks!


__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"

 

Could still be an ignition problem, despite all you've changed. Sudden
onset and all. I'd also check your EGR is not stuck open.

 

I think I may have stumbled upon something- more background. The
seller was not totally honest about the car (no surprise there) but
the shop who serviced it was also less than forthwith as to the car's
condition. Based on what I have seen, I think this car sat unused for
a while. I don't think it was too long, but for a car that has just
short of 190,000 on it, long enough to create some difficulties.

I got a Mityvac unit today and hooked it up to a few things- among
them the fuel line pressure regulator, which I worked a few times with
the vac pump. I think it might have been just a bit sticky, and I
think it is now working better. Additionally, the other problems (old
distributor cap, rotor, plugs, and wires) which needed changing were
also a small part of the problem. Add to that I found a few slightly
loose vac lines- just a bit, mind you, as well as a dirty vac port on
the flame trap... getting the picture? There wasn't any one thing
terribly wrong, but a lot of little things which cumulatively added up
to a rough running motor.

So.... With those other problems going on, when I adjusted the
throttle plate's stop screw, the throttle position switch, and the
throttle linkage, I got it wrong. Seemed OK at the time, but with the
other problems it made it difficult to tell what was going on, and I
had adjusted it with the throttle too open. Remember that these
engines have the idle controlled by the computer by varying the
mixture (this one has the two-wire idle air control which is either
open or closed, I think. In any case it doesn't vibrate like the one
on my 960, but seems to be binary...?). When the throttle is too open
it throws off the idle mixture because the computer is dealing with
air through the calibrated Idle Air Control valve as well as the air
getting past the throttle plate in the throttle body. So off idle
performance suffers in the transition between idle and just off idle.

So, it goes to show that 1, a little knowledge is a dangerous thing,
and 2, these cars are quite complicated and the systems are so
interrelated that it can be difficult to find small problems.

Now, if I can just figure out why it keeps posting a 1-2-1 code for a
"Bad/missing signal to/from AMM." Yup- did it again while I was
adjusting the idle and throttle... :-/

__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"

 

Have you moved the coil wire away from the MAF sensor cable this will
also set 121 a wire tie will do attach to a brake line @ the master Cyl

--
"*-344-*Never Forgotten"
Is for the New York City Firemen who lost their lives on September 11,2001.
The official count is 343, but there was also a volunteer who lost his life
aiding in the initial rescue efforts. And I will never forget them as
long as I live,
nor should any American.

 

I wouldn't have thought of that! I don't think that it is an issue
with my car....

On the '90 245, the coil is mounted in a bracket on the front of the
driver's side strut tower along with the power steering reservoir, and
the distributor is on the left front side of the motor, so the coil
wire runs in a long, straight line from one to the other.


__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"

 

....and in the case of my '83 245, the coil wire ran right behind the
power steering reservoir. While underway, the wire rubbed up against the
tank enough to wear the insulation off the wire and short to ground.

 

Hmmm:

1. bad connection at the plug into the AMM or bad wires to AMM?

2. bad AMM?

 

Those were my first two guesses. I pulled back the boot and the wires
look and feel good. The AMM is more difficult to test. If I had a
spare it would be a lot easier, but they don't come cheap. If it keeps
posting the code I think I will shop for a used one.


__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"

 

If I understand correctly, the AMM can be tested with an ohmmeter.
There have been several references to this on the newsgroup. I think.

 

There are some basic tests that can be done, but my problem seems
intermittant and so I am not sure how effective they might be in
finding my problem. I have other things to deal with as well to
eliminate any other possible source of the casue, but at least for now
it's running decently.


__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"

 

Randy
I had almost exactly the same symptoms as you describe on my wife's 1989 240 and
checked a bunch of the same ignition and fuel system parts. What the problem turned
out to be was a backfire or something had popped out part of the intake manifold
gasket and caused a vac leak in cylinders 1 and 2. Wouldn't have found it but a
sharp eyed friend looking at it with me said "what's that" and pointed to the piece
of paper gasket hanging below the manifold.
I got a new gasket and installed and torque the manifold properly and the problem
has not reappeared.

Now my off topic question on a 1989 240L
The odometer stopped working this weekend. Would a change of what the Haynes manual
calls the "speedometer sensor" in the rear axel housing be the fix?

Also we have problems with the Overdrive switch on occasion locking out the OD when
it wishes to, and no ammount of pushing the button will turn it off. Would the OD
relay be the culprit?

Some on let me know.

Big Al in Birmingham AL

 

The sensor controls both the speedo and odometer so if either is working
then the problem is in the guage itself. The two most common problems are
bad solder joints on the circuit board in the speedometer, and the gear that
drives the odometer can sometimes break but the latter is more common on the
pre-'86 cable driven speedos.

Yes, that's almost certainly the problem, at least if the arrow light is
coming on but it can be either way. Again solder joints are the usual
culprit, or you can just replace the relay.

 

My speedo in my 90 every once in a while will just drop to zero, a good
smack or a few on top of the dash will get it reading again.

I read your reply to mr brown:

Where are these bad joints? I had my speedo out but could not fnd anything
that even under magnification looked faulty.

Thanks in advance.

Duane

 

On the circuit board inside the speedo, in my experience nearly all the
joints are poorly done right from the start and look cloudy, I suspect they
may have used lead free solder or poor quality flux, it can be tricky to
resolder them nicely too, I had to use a desoldering iron to suck off all
the old stuff one joint at a time, tedious but it worked.

 

Thanks, I'll look for the more cloudy solder caps.

Duane

 

Look (with the magnifying glass) for teeny hairline cracks running around
the joint. They are normally at the base of the cone, but they can be at the
top where the lead protrudes. Depending on your age, you may need direct
sunlight or equivalent to see them. That's how it is with me since I turned
50, but when I was young I could see them without magnification in room
light. Sigh.

Mike (the elder)

 

Thank you James and others for the replies.
My Speedometer seems to have a mechanical cable from the manual, but I haven't
opened it up yet to be sure.
Only the Odometer is out, the Speedo works fine, along with the rest of the gauge
cluster.
If it is solder joints where should they be?
My manual does have wiring diagrams, and the sensor does go strait to the ODO in the
diagrams.
Thanks again for the swift replies.
Al Brown

 

If the car is an '89 the speed is not mechanical, the last year that was
used was '85 in a 240, every Volvo since then has been electronic.

 

For the end of teh story, see the thread:
It's RUNNING!


__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"