[urq] RE : Data point for hard starts when hot....

[DGraber460 at aol.com]

In a message dated 4/22/2006 8:54:43 A.M. Mountain Daylight Time,  lar
aa at sympatico.ca writes:

Well,  Martin, I think you might want to revise your judgment of the
injector  cooling fan. It is indeed a lot easier to start now, like it
always  did.

And to add another data point, I reinstalled my own stock ECU (I  was
using Brady's chipped ECU since February) and unplug the  injector
cooling fan switch, to rule out the fact that a chipped ECU may  be
harder to start when hot. 

Result: yes, the engine is very long  to start when the fan is not
working, even with a stock ECU. Later the same  day, I reconnected the
switch, drove the car on the highway, stopped,  waited 15 minutes, and
she restarted right now ! So maybe the German  engineers were right when
they mandated this system on the Turbo CIS  cars... It has a role, even
if it is just to prevent evaporation when the  engine is stopped.

BTW, those of you who have problems with hot starts,  be sure that the
"intake" hose of the injector cooling fan is there, as it  draws cool air
from bellow the engine compartment... Item 17, page 1-33,  18-00
(http://filebox.vt.edu/users/rfitton/ETKA/1_33_18-00.pdf)  

Louis-Alain


> Let us know... I found it to be useless in  Canadian
> summers anyway.
> The real problem was usually a leaky  injector or system that did not
hold pressure for one or another  reason.
> --
> Martin Pajak
> 
> 
> >  Louis-Alain Richard
> >
> > So today, which is as hot as  yesterday, will prove or
> contradicts that
> > this fan has a  real role in helping the hot starts.
> Fingers  crossed.


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Louis-Alain,
Your observations verify what I have been saying for years. These cars  
vapor-lock very easily. I have been having an increasing problem with this  due to 
the increased content of ethanol in our Rocky Mountain High  gasoline. The 
more ethanol the lower the boiling point of the fuel, and  consequently the 
greater tendency to vapor-lock even in winter. The  presence of a tech bulletin 
directing the opening of a hole in the injector  cooling diffuser to cool the 
injector lines also confirms what I have found. 
I have to date used several adaptations to cure the issue. The hole in the  
diffuser modification helped. A hood vent helped. A timed relay to run the  
injector fan for a set amount of time was almost 100%.
On my current car I have wired the fuel pump and the cold start injector to  
2 manual override switches. This has been a 100% cure. I just run the fuel  
pump manually to circulate the "air bubbles" back into the tank (you can very  
audibly hear the bubbling of the air back into the tank) and then bump the cold 
 start valve to get it to fire which lifts the air plate, and bingo - fires 
up  every time.
In OE state the cars will work fine with late eighties formula gasoline,  but 
not with the current issue from our petrol  empires.   

 
Dennis
Denver