It has been suggested that because the 1990 Civic is blowing back
through the throttle body that perhaps the timing belt has jumped.

TeGGeR® made the follwoing comment:
The distributor is driven off the camshaft. If the timing belt has
jumped,
the timing will be so far off that it should be glaringly obvious.
Short
the grey connector hidden behind the top of the passenger-side kick
panel
first. If the belt has jumped a tooth (or more) it can definitely
result in a no-start condition. The ignition timing check will confirm
this.

If you turn the steering wheel all the way to the left, you should see
a
rubber plug about 1-1/2" in diameter set into the splash guard inside
the
wheel well. Pull that and a 19mm socket will fit onto the crank pulley
bolt.

Turn *counter-clockwise* and the engine will revolve (assuming the
tranny
is in neutral). Turn until the marks on the crank pulley (the middle
one of
the group of three) are in line with the timing mark on the timing
belt
cover. This will enable you to find TDC on the #1 cylinder.


--
TeGGeR®
-----------------------------------------------------------------------

The Civic is located about 20 miles from where I live, so I am
depending on a 17 year old girl to do some pre-testing before I arrive
Monday. I took the valve cover off Saterday to see if the belt was
broken or worn. We used a 3/8" 14"
long dwoel to find #1 TDC. I wanted to check each cyl to see if the
valve behaved correctly. I didn't even think of using the timing marks
on the cam
and crank pullies to check timing. I forwarded the above text to her
and she
made some tests.

She says that the camshaft pully does not have "top" like those shown
in her Chilton or Haynes manual, and the TDC mark is not exaclty like
the one shown either. But that the 3 marks on the flywheel pully are
maybe 5 degrees beyond the timing mark when #1 is TDC. There is a
white dot, like the 1984~1987 flywheels, shown in the Chilton manual,
that almost aligns "perfectly"
with the timing mark.

I checked my flywheel and if there is a white dot I can't find it. I
have the 3 marks about 1/4" apart and my flywheel pully looks clean.

I will look again monday morning before we go over for a barbecue.
I have the same Chilton manual and sure enough the pictorial for the
84/87 shows the three marks, followed by a whte TDC mark. I wish it
had not started raining! One web site pointed out that the timing
marks are about 18 degrees before mechanical TDC, and they represent
the firing starting point
for ignition, which is advanced.

The belt is less then a year old, was installed by a local machanic
who
has a very good rep (he is in Iraq or we would bother him), and all
the
parts (T-belt, water pump, tensioner and spring are OEM Honda ordered
from Majestic.

Off the top of your head any idea how far would each tooth be in
degrees?
What are the chances of a "good" timing belt jumping a notch?
I was testing her water damged ECU and the engine attempted to start
and
the hicuped or burped, what are the chances that a faulty ECU cause
a backfire or other event that would cause an otherwise good belt
to jump timing?

I have detailed directions (from the web) showing how to change a
CRX belt, and the civic is very similar. I am hoping that when
the machanic reinstalled the crank bolt that he used less then
1 gigaton/inch of torque! She watched the orignal belt replacement
and says that she "thinks I can do it".[The "I" being her.] With
the engine out of the car, I am fairly certain that I could change
it. But doing it inplace looks a bit chancy and tight. The
directions I have say to put a jack(topped by a wooden block)
under the engine, lossen and remove the crankside engine mount
and lower the engine to gain access. Assuming the crankshaft
bolt will come loose it appears fairly straightforward.

She is machanically inclined, wants to be a mechanical engineer and
has routinly taken apart everything from the kitchen blender to a
Briggs and Stratton lawn mower with good outcomes.

Would it be stupid to back off the tensioner and slip the belt
back into correct timing?

Sorry this is so disjointed, but I am writting this in a hurry
before friends come over for supper.

Terry