[DeTomaso] Unhappy motor - looking for suggestions

[Charles McCall]

Hi all

 

I just got back from a Supercar event in northern Spain with 35 cars
attending - Lambo, Ferrari, Viper, Porsche, and, as usual, a lone DeTomaso!

 

The highlight for me without a doubt was an 8-minute burst on the highway
with the police clearing the way for us, cruising at a steady GPS-indicated
180 k/hr in a 35 car convoy. the people out for a Sunday drive must have had
their minds boggled. 

 

Anyway, my engine is not happy. This morning in the hotel parking lot I
really thought that we'd have to skip today's event because it wouldn't
start and didn't sound like it was even thinking about starting. Took
probably 5 minutes of crank-wait-crank-wait before it fired. Yesterday at
the gas station it took 2-3 minutes to start, something that has never, ever
happened before. It is really hard to describe the problem so much of it is
"feel", but I'll do my best. 

 

A few weeks ago I noticed that the engine would tend to stumble if I would
floor the throttle, then clear its throat and pull. For example, I like to
heel-and-toe, just because, and when blipping the throttle it would stumble
instead of rev. The engine also felt a little rougher, as though it vibrated
more than I remembered it. I don't remember if this was before or after I
did a short tune-up, by adjusting the valve lash (I have mechanical
lifters), and cleaning the K&N air filter by applying K&N filter oil, etc.
or if it is irrelevant. So I was messing around in the engine bay recently.

 

This weekend the engine felt considerably worse. It felt like it would
stumble under partial throttle as well. It would stumble a little bit under
trailing throttle going downhill as well, so I don't think it is a clogged
fuel filter. 

 

Oil temp is perfect. Oil pressure is perfect. Water temp is perfect. The
engine idles perfectly. But if you floor the gas from idle, it'll stall. The
engine doesn't feel crisp, it feels bloated and soft, if that makes sense.
It feels rough, and it feels like it occasionally stumbles under constant
throttle at highway speed. It pulls hard when accelerating, but I don't
think as hard as it used to, or as high (I have a 6500 rpm limiting chip in
the MSD that it used to pull very easily to). 

 

Suggestions for where to begin looking? And other info that would help in
troubleshooting? 

 

 

-------------- next part --------------
   Hi all


   I just got back from a Supercar event in northern Spain with 35 cars
   attending - Lambo, Ferrari, Viper, Porsche, and, as usual, a lone
   DeTomaso!


   The highlight for me without a doubt was an 8-minute burst on the
   highway with the police clearing the way for us, cruising at a steady
   GPS-indicated 180 k/hr in a 35 car convoy... the people out for a
   Sunday drive must have had their minds boggled...


   Anyway, my engine is not happy. This morning in the hotel parking lot I
   really thought that we'd have to skip today's event because it wouldn't
   start and didn't sound like it was even thinking about starting. Took
   probably 5 minutes of crank-wait-crank-wait before it fired. Yesterday
   at the gas station it took 2-3 minutes to start, something that has
   never, ever happened before. It is really hard to describe the problem
   so much of it is "feel", but I'll do my best.


   A few weeks ago I noticed that the engine would tend to stumble if I
   would floor the throttle, then clear its throat and pull. For example,
   I like to heel-and-toe, just because, and when blipping the throttle it
   would stumble instead of rev. The engine also felt a little rougher, as
   though it vibrated more than I remembered it. I don't remember if this
   was before or after I did a short tune-up, by adjusting the valve lash
   (I have mechanical lifters), and cleaning the K&N air filter by
   applying K&N filter oil, etc. or if it is irrelevant. So I was messing
   around in the engine bay recently...


   This weekend the engine felt considerably worse. It felt like it would
   stumble under partial throttle as well. It would stumble a little bit
   under trailing throttle going downhill as well, so I don't think it is
   a clogged fuel filter.


   Oil temp is perfect. Oil pressure is perfect. Water temp is perfect.
   The engine idles perfectly. But if you floor the gas from idle, it'll
   stall. The engine doesn't feel crisp, it feels bloated and soft, if
   that makes sense. It feels rough, and it feels like it occasionally
   stumbles under constant throttle at highway speed. It pulls hard when
   accelerating, but I don't think as hard as it used to, or as high (I
   have a 6500 rpm limiting chip in the MSD that it used to pull very
   easily to).


   Suggestions for where to begin looking? And other info that would help
   in troubleshooting?