Re: [T3] Piss poor mileage

[stans4@ix.netcom.com (Stan Schaefer)]

An ignition switch shouldn't have anything to do with poor mileage,
it's probably coincidental.  You could have  a charging system going
bad, though, per Jim, low voltage causes a rich condition.  

Here's my drill though:

Check the throttle position switch, since it's '71, you should be able
to turn the ignition switch on and hear 20 clicks as you operate the
throttle.  If you can't, check the switch contacts, a gentle cleaning
with an eraser will help.  I've had wires inside break, too, easy to
fix. If the switch is OK and you still can't get clicks(injectors are
firing), check the continuity of the harness to the control box.

The usual air leaks in the hoses and seals will cause a rich
condition, usually, though, you can't get a good idle and that's a
hint.  Pull a plug and see if it's really black.

You might have a leaky injector(or more).

The factory cloth-covered fuel hose will crack and you can't see
where.  I've had it leak for a while without finding the leak, I've
smelled gas, but it never dripped, the cloth covering wicked it away.
The only way to check it is to ground the pump at the terminal in the
back and visually inspect the covered lines from front to rear.  If
you haven't replaced hose in a while�:�ht be the time to do it.
Cracked hose will cause hard starting, too.  T3 flambe if you're not
careful.

You do NOT need a FI tester, a cheapie digital or analog volt-ohmmeter
works just fine, they've had DVMs for $10 at Harbor Freight recently,
no excuse to be without one.  Even a buzzer or light bulb with a
couple of batteries will work for checking continuity.  The
temperature sensors need to be checked with an ohmmeter, unless
they're open, shorted or wildly off value, they probably are OK.

On Thu, 27 May 1999 19:51:16 -0700, you wrote:

>Okay,
>It's been a few tanks, and I can't figure it out.  My mileage has been
>pretty good (23mpg city) for quite some time now, but it has suddenly gone
>to about 14-15 mpg the last four tanks.  Here is the history of what was
>leading up to this:
>
>1) Ignition switch burned out, so I replaced it. Everything worked fine, but
>I was not paying attention to mileage.
>2) The car was being a little sluggish about a week later--poor
>acceleration, poor mileage.
>3)  It stalled in traffic, which resulted from loose battery cables (I
>didn't fully tighten them after replacing the ignition switch--ie, user
>error).
>4)   I tightened the battery cables. The acceleration was better, but the
>mileage did not improve.
>5)  I performed a tune up without replacing parts. No improvement in
>mileage.
>6)  It is about time for a tune up anyways, so I am about to replace the
>cap, rotor, spark plugs, condensor, air intake boot.  Besides,
>unfortunately, I am going on a big road trip (already paid for it) this
>weekend.  Perfect timing for the wonderful mileage.
>
>I read in Bentley that  "high fuel consumption" is a result of a failed
>sensor.  Which one?  Well, they said to test it--only Toby has a tester.
>They also stated that it could be a mix up with the + and 50 wire vs the 30
>and 50 wire (Bentley, 4-10.3 table A. "Basic fuel injection troubleshooting
>guide" entry #8).  I don't think I changed any wires there, but here is a
>little story about the ignition switch:
>
>There wt!\�nition switch '71 t3 specific available, so I had to use a
>B*g ignition switch.  The wire harness was not the same.  I removed the
>wires (soldering) and replaced the same wires (matching the colors) to the
>switch.  There was one extra terminal on the switch, so I left it empty.
>
>So, any hints on why I am suddenly getting 14 mpg?
>
>Steve
>
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