car cutting off

[MLJ]

To anyone who can help me- I have a '91 740 Turbo. Lately it has bee
cutting off sporatically when I am turning into a parking space o
turning out of a parking space. Today it cut off in slow traffic.
took the car to one Volvo mechanic who said it was the fuel pump relay
which he replaced. The problem continued. I took it to another Volv
mechanic that said I needed a tune-up which he did. The problem stil
continues. When I called him back he now says it might be the fue
pump. Can anyone tell me if this sounds like a fuel pump problem? I
there a way where they can look and see if the fuel pump is going bad
Help!

ML

 

[Michael Pardee]

To anyone who can help me- I have a '91 740 Turbo. Lately it has been
cutting off sporatically when I am turning into a parking space or
turning out of a parking space. Today it cut off in slow traffic. I
took the car to one Volvo mechanic who said it was the fuel pump relay,
which he replaced. The problem continued. I took it to another Volvo
mechanic that said I needed a tune-up which he did. The problem still
continues. When I called him back he now says it might be the fuel
pump. Can anyone tell me if this sounds like a fuel pump problem? Is
there a way where they can look and see if the fuel pump is going bad?
Help!

MLJ

Fuel pumps don't often become intermittent - they usually stay bad once they
quit. There are a few common causes of this sort of dying (and the fuel pump
relay was a good suspect, even if it didn't fix the problem) that the gurus
here can help you with. I'm thinking about the crank angle sensor myself,
but don't spend money on my guess ;-)

A cheap thing to check is the condition of the connections at the positive
battery terminals. Our '85 765 turbo - somewhat similar to your car - had
problems with cutting out in left hand turns. It turned out to be the
connection where the lone wire attached to my positive terminal - apparently
the stresses of turning left stirred up the bad connection. When you take
the car back for whatever work the gurus recommend, having the battery
connections cleaned to ward off evil spirits might be a good thing.

Mike

 

[Bev A. Kupf]

Fuel pumps don't often become intermittent - they usually stay bad once they
quit. There are a few common causes of this sort of dying (and the fuel pump
relay was a good suspect, even if it didn't fix the problem) that the gurus
here can help you with. I'm thinking about the crank angle sensor myself,
but don't spend money on my guess ;-)

I agree with Mike - I don't think that fuel pumps go bad gradually.
But the intermittent problem that you have could be the radio suppression
relay (its also called the fuel injector relay).

I don't know where it is in a '91 740. It was moved around in the engine
compartment by model and year.

Beverly

 

[Michael Pardee]

I agree with Mike - I don't think that fuel pumps go bad gradually.
But the intermittent problem that you have could be the radio suppression
relay (its also called the fuel injector relay).

I don't know where it is in a '91 740. It was moved around in the engine
compartment by model and year.

Beverly

I knew the experts would be here soon - thanks, Beverly! Mike F has
mentioned the relay and an identical one that are beside each other in some
models, and that they can be simply swapped to determine whether that is the
problem, but again I don't know about a '91 940T. I can't even find them in
my '85 765T.

Mike

 

[Bev A. Kupf]

Mike F has
mentioned the relay and an identical one that are beside each other in some
models, and that they can be simply swapped to determine whether that is the
problem,

Hi Mike - dead on recollection of what Mike F posted. That would be the
electric cooling fan relay.

but again I don't know about a '91 940T. I can't even find them in
my '85 765T.

Your '85 wouldn't have one. The fuel injector circuit was not isolated
until the '86 models. My understanding is that 7(4|6)0/940 series used
them from '86 until the last model year of the 940.

Beverly

 

[Michael Pardee]

Hi Mike - dead on recollection of what Mike F posted. That would be the
electric cooling fan relay.


Your '85 wouldn't have one. The fuel injector circuit was not isolated
until the '86 models. My understanding is that 7(4|6)0/940 series used
them from '86 until the last model year of the 940.

Beverly

Thanks - at least I can stop looking for mine!

Mike

 

[MLJ]

Thanks to you all! I now feel like I have some knowledge and I a
prepared when I take the car back in. Thanks again!

ML

 

[Mike F]

Thanks to you all! I now feel like I have some knowledge and I am
prepared when I take the car back in. Thanks again!

MLJ

Hopefully the tune up you got included a cleaning of the throttle body
and idle air valve, as these 2 things gunking up is a major cause of
your stalling problem.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)