Hi gang-
My TR6 has recently begun, on occasion, to suddenly lose power out of
nowhere, though not cut out completely, and then in a short while pull
itself back together again and continue running fine.
The symptoms are the car will suddenly begin to run like its gasping for
something. For you medical types, its kind of like a steady heartbeat
suddenly erupting into spasms of arhythmia. A total change in engine
sound and pitch accompanies, like a low humm or buzz. It always happens
while I am either running under power and in lower gears while
accelerating, thought not hard acceleration, or when holding at a lower
speed. It never happens more than once on a trip, but is happening with
increasing frequency. The engine doesn't cut out, just no power. I can
maybe get the rpms up to 3000-3500 at best in revving though for some
reason revving seems to make it worse as its occurring. I find if I put
it back into gear and stay on the accelerator, it will pull itself out
of the gasping arhythmia and back to steady running within a minute or
less. It's never died completely of this and doesn't recur on the same
trip. There is some mild popping sounds when the condition occurs, but
no particularly bad smell, smoke or fuel odors. It has happened on both
hot and mild days, so it seems unlikely to be vapor lock. It has always
happened on straight and flat roads. Unfortunately it always happens in
a busy place so I can't get out and look in the engine real-time.
The gas tank is an aluminum tank installed 3 years ago, a 3 year old
stock mechnical fuel pump, the incoming filter is new and clean (clear
bowl). Unchecked is the mid-line fuel filter (large canister type not
see-thru). There is an AC fuel pressure meter on the fuel line and I run
dual Weber DGV's. I have an ignitor ignition, new sport coil and new
ignition wires. I have done nothing lately to adjust anything in the
system. I have checked all vacuum hoses visually and they appear to be
tightly connected.
I'm guessing its somewhere in the fuel system, though I am open to the
idea it may be somewhere else. But before I start going through it and
replacing parts end to end, I thought I'd ask where I might start first
and what order to go through by highest likelihood of cause.
I know there have been tons of such incidents reported on the list and
lots said about them but my memory is getting weak with age. Off-list
responses are fine if anyone thinks they can help.
TIA
Keith Ehrlich
74 TR6 "Gasper"
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