1993 850 doesn't want to restart after short drive

Hi all,

I have a 1993 850 GLT that has been sitting for the past five
[winter] months. It was started every two weeks or so, and
taken on a short drive once a month, but that's it. I've started
to drive it again... once a day, up the road 2 miles to the
convenience store. When it is cold, it starts up perfectly. But
when I come out from the convenience store and try to restart
it, it doesn't want to start. It will turn over for 5-7 seconds
without seeming to fire, then sometimes it will start to fireup,
but I have to give it just the right amount of gas at the right
moment and then keep the revs up. I have to be carefull not to
let the revs drop on the way home or it will stall and then be even
harder to start. So far I've been lucky.

Does this ring any bells with someone? Might things improve
once I've polished off the old tank of gas? I'd like to take it
for a good long drive on the highway, or to the dealer, but I'm
not sure how it would act.

 

Classic case of it being carboned up and flooding from the short runs. These
engines really do not like cold starts followed by shut down and re-start.
You are actually quite lucky it will re start at all.

Get some fresh fuel in the tank, and take it for a fast hard drive of
50miles +, plenty of load and high revs and it will feel alot sharper after.

Tim..

 

Carboned up as in what? Fouled spark plugs? Gunked up fuel
injection?

Are there any additives that help with that? Would cleaning/replacing
the spark plugs serve the same purpose?

Thanks

 

Additive: Chevron "Techron" every 5 to 10k miles will keep fuel system
clean. I've used it for years, and my local Volvo dealer uses it every 10k
on all cars they do maintenance on. If you use an exclusive diet of Chevron
gas, you probably won't need to use the additive as Chevron contains Techron
in the gas.

 

And start using Chevron Techron. It is about the best thing there is to
prevent or remove carbon deposits. It comes in Chevron gas but is
available as an additive for any gas.

 

Does our temperature gauge work properly?

The reason I ask is that the temp sensor failed on mine recently. It went
intermittant. With the sensor 'offline' The car would start fine when cold,
as you describe, but when heated up ran like a bag of spanners ...again as
you describe....

 

AFAICT the gauge is behaving normally... ie initially reading
cold and then indicating increasing temperature as the engine
warms up. How did you know your temp sensor was bad?
Did your gauge reflect an obviously wrong reading? Did you
put a meter on the sensor? Engine code?

 

I believe these cars have hydraulic tappets and after a short drive oil
gets under the tappets and therefore the valves do not close properly
therfore no compression to fire against - probably.