Type 44 Thermo Switches & injectors, o2 sensors and....

Ben Swann bswann at worldnet.att.net
Tue Nov 12 11:50:07 EST 2002


Mark,

I had these symptoms when I did the engine rebuild this spring - I had
probably already had noted them, but attributed it to cracked manifold
which precipitated in all the work.  I had an aggravating time getting the
car to run right and it was very frustrating and I was kicking myself and
thinking I did a botch job.  I even pulled out the nice performance cam,
because I thought it was screwing things up, but it wasn't.

Here are some of the marginal components I replaced:

Fuel injectors - they had just been replaced in the last 1 1/2 years, but I
confirmed at least two of the injectors were leaking down ( I actually got
Bosch to send me one replacement).  I finally replaced the entire batch for
the second time.  It helped, expecially with starting, but things still
weren't as expected.

Fuel pressure checks and swapping pressure regulators - NFG as there was no
real problem there, but system pressure regulator o-ring could be/have been
a contributing factor.   I had done this stuff before the fuel injectors,
as I assumed they were good since I had just replaced them.  A S S U M E
!not!

Of course I checked and double checked all vacuum lines.

Replaced the Oxy sensor - car did run even  better, and had a performance
increase.

The MF thermo-switch also was going bad and finally died causing the
coolant light to go on  - I had just repalced that a couple years ago too!
 $85 POS!  That helped a little too.

Finally, I replaced the fuel pressure accumulator.  Don't think it was
absolutley necessary, but I have piece of mind.

The car now generally starts within 3 revs/2 seconds even when cold, and
when warm can bump start the engine in gear or with starter - click VROOM!.

I almost never hear my after-run fan and had to do some digging when very
hot to see if the pump was going on.  I also found in both ot the avants
the impellers were locked up, even though you could feel the motor running,
so beware, all is not as it first appears, and I replaced the pumps with
working units.

Hope this helps.

Q-list in copy.

Ben

On Tuesday, November 12, 2002 8:48 AM, Mark Woodland
[SMTP:markwoodland at hotmail.com] wrote:
> Ben,
> Thanks for getting back to me.
> Last night I went about half nuts tracing the problem,
> and finally traced it to a wire that had pulled out of a
> terminal junction point under the dash, between the fuse block and the
> relays.
> So, now I have the circuits hot to the relays, and I can ground the temp
> switch on the wastegate heat shield and get the injector cooler blower
 to
> come on, and I canshort the two terminals on the temp switch at the
radiator
> hose outlet at the head, and get the rad fan to turn on, but I haven't
been
> able to get the thing hot enough to have either circuit turn on
> automatically.
> In the meantime the problem remains that once the engine is up to temp
and
> turned off for 5 minutes, the engine won't start for hours and hours..
> until the engine temp drops below 75F or so, which on a hot day can take
all
> day.
> When it finally starts, it starts on one cylinder, then two, then picks
up
> all 5.
> All of the injectors have been recently replaced, as has the fuel
> distributor head. Do these symptoms ring a bell?
> Mark
>





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