[s-cars] Smooth to Rough to Smooth to Rough

[JC]

That's a real good start for a list. Sounds like it's dropping a cylinder
one way or another so ignition followed by fuel.  The big add I'd have would
be a bad POS as the other extremely common known failure and if a POS
channel has completely crapped out then this is exactly the kind of thing
you'd get.

But start here:

If it is running badly consistently that's actually 'great', especially if
it happens at idle.  That means you can let it idle in the drive while you
disconnect one injector at a time. If runs worse when you unplug the
injector, then that cylinder is not the problem. When you pull an injector
wire and nothing changes you've found your non-firing cylinder and you can
start to zero in on ignition and fuel for that one. If all injectors are the
same (aka make it run worse), then it is a "system wide" problem like fuel
or air.

Have fun and good luck!

JC

>
> Fuel supply problem
> cracked coil pack
> cracked spark plug
> broken ignition lead
>
> Suggestions welcome before his timer starts ticking.
>
> Brian
>


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