89 Caravan 3.0 Chasing problems.. Help!

I'll give a brief history:

Van ran fine, then developed a stall-like hesistation when first
accelerating from a stop when engine warm but not cold. This turned worse
within a few weeks but was still drivable. Finally, the van would only
sputter, maybe it was even a backfire, it was obviously misfiring.

I was able to put a scan tool on it. I received a code of 26. This is a fuel
injector bank high resistance code. Fine; I replaced all the injectors and
cleaned and very lightly greased the connectors of the injector harness. The
van started but was still sputtering or missing. But it was a huge
improvment over its' previous operation. The code went away as well.

I put a timing light on the engine and observed the timing mark jumps
between about 10 and 15 deg. btc. I have also checked the MAP sensor and the
coolant temp sensor, both appear to be operating normally. The distributor
cap and rotor as well as the plugs have been changed a few months prior to
this all starting. The old parts looked 'normal' in wear.

My questions:
Where would be a good place to start looking for the problem? (Van still
sputters/misses. Some stalls when starting from stop sign. No trouble codes)
On a wild thought, could this be a problem with a the timing belt? The
timing mark jumping around did not look right to me.

Before I go further in chasing rabbits, I'd greatly appreciate some insight
from all of you. This has been a great little van with no other problems in
150k miles. Only replaced the normal things so far.

Thanks for any replies!

Ric

 

codes)

A good place to look is all the spark plugs. Make sure they are all
tight; a friend of mine had a 90 lebaron (same engine) with the same
problem and it turned out one of the spark plugs came loose on the back
of the motor. Tightened all the plugs and it ran great ever since.

Have you replaced the belt recently (or have someone else replace it)?
If it hasn't been changed it wouldn't hurt to change it since the van
has a considerable amount of miles (only if it needs it though).

Hope this helps!

 

If the engine runs fine when it's cold and when it's warm it misfires in
all RPM ranges, you might have a bad coil. Coils sometimes go bad
this way - they work fine when cold then when they get hot the windings
inside move around as the coil expands, and short against each other.

Another possibility are bad plug wires, but I would try another coil first.

Ted

 

My 95 GC behaved this way, so I took it to my mechanic. He changed the
spark plug wires and it's run great ever since.

Brigitte