'91 100q 5 injectors replaced - now car wont start

Mike Arman Armanmik at earthlink.net
Thu Jun 27 12:33:23 PDT 2013



Have you run a compression test on this engine?


My feeling is that yes, it is going to be something "dumb" (which we've all done at one time or 
another).


If you drove the car to where you worked on it, as was mentioned, you could NOT have magically blown 
a head gasket while the car was sitting - and even if you had, you wouldn't lose compression on ALL 
the cylinders. If the gasket blows between two cylinders, three will still show full compression. If 
it blows out to the water jacket, four will still be good. There is NO WAY a blown head gasket will 
lose the compression on ALL the cylinders.


Gas - compression - spark. The basics. Don't go taking things apart until the diagnosis is made.

If and only if the timing belt slipped, you just might have some bent valves (is this an 
interference engine?) and then you'd have to pull the head, and *then* yes, you could lose 
compression on all the cylinders. Andy why would it choose to slip "just then", right when you 
changed the injectors?


Establish what is already correct first, you want to find something specific before you start taking 
stuff apart.


I've taken vehicles to places for a diagnosis, and I am invariably told that I need the most 
expensive part - and when I fix the thing myself, that was never what was wrong. Don't fix your car 
by throwing money at it. Fix it by finding out what is REALLY wrong and fix *that*.


When I fix stuff for other people, I always ask "Who was the last person who worked on this and what 
did they do to it?" Start there . . .


Best Regards,

Mike Arman
90V8Q, and a BUNCH of other stuff


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