[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]
Whoa, wait a sec! I know if you have a cylinder temp head sensor it is quite
critical. My '75 Porsche 941 1.8L, which uses a Type IV motor like all 914-4's,
has a cylinder temp sensor. If this sensor fails, the engine will not operate.
Period. I know because I went through Wallet-Hell (spent money) before I
finally replaced the sensor. Once I replaced the sensor the engine ran
beautifully!! For a Porsche the part cost less than $50 and I replaced it
myself (it's kinda tough to do since you're doin' it blind).
Don't give up yet. Disconnect the negative cable (ground) from the battery.
Grab a wire bristle brush and clean every electrical connection you can get your
hands on. Use emery cloth too, it needed. Then LIGHTLY coat the connections
with electrical grease or WD-40 (this helps keep away the corrosion). Replace
worn wires, cover all connections to keep them from shorting out. Make sure the
battery is in good condition. Clean *all* grounding straps thoroughly! You
want your electrical system in top notch, conductive condition. While you're at
it, clean the fuse box and fuses, remove all of the corrosion, make the metal
shine! Now, go back and put the negative cable back on the battery. Assuming
that the ignition switch is working (the starter engages and turns the engine),
you have fresh gas and a new fuel filter, try to start her up. If she still
doesn't work, hey, you tried your best. Either trouble shoot the components of
the FI or sell her as you planned.
Toby Erkson
air_cooled_nut@pobox.com
modified '72 Squareback 2.0L
stock '75 Porsche 914 1.8L
______________________________ Reply Separator _________________________________
Subject: Re: Faulty injection system
Author: type-3-errors@umich.edu at SMTPGATE
Date: 10/16/96 10:38 AM
On Wed, 16 Oct 1996, mark R lewis wrote:
> dear greg, i have had the ECU checked by a pro and there is
> nothing wrong with it so it must be a sensor proper beyond
> that i cannot say.
> Mark
Hi Mark,
the temp sensors are not that expensive, and only really play a
big role during warm-up. If you were *really* nuts, you could replace
them with dash-mounted variable resistors...
The temp sensors are little semiconductor devices whose
resistance *decreases* as they get hotter.
The sensors that remain are the manifold pressure sensor
(critically important) and the throttle position switch (also important).
The pressure sensor is how the brain determines how much air is being
ingetsted by the engine. The throttle positioner lets the brain know if
you floor it, so that it can enrich the mixture--just like an accelerator
pump on a carb. Oh--I suppose that you would also consider the extra pair
of points in the base of the distributor to be a kind of sensor--if these
aren't sending a signal, the injectors won't ever open!
-Greg
'71 squareback
'63 Beetle