Looking through list after list of Volvo info, I thought I would check
our fuel pressure relay. It looks like it might be the culprit.
Can someone explan to me how this is supposed to work? I understand
how relays work, here is the scenario for ours (observed in the car
just now (it's minus 32C, so excuse the rough sentences, talk about
lousy weather to diagnose a stuck car!!).
If you are looking at the relay installed (BTW, we have the white
plastic relay in our 1988), but with the cover off, there are two
coils. The left and the right. When I turn the key in the ignition to
position three ("on"), this relay clicks. The other relay remains
motionless and there is no noise from my fuel pump. Being a bit of an
idiot, I figured what happens if... So carefully inserting a tiny
screwdriver to close the second relay (the right hand side), I noticed
that then I could in fact hear the fuel pump merrily whirring away.
Still the car will not start.
Can someone explain just what is supposed to be the sequence of
operation in a functioning fuel pressure relay? Which side should be
closed? Opened? When?
The car is still cranking wonderfully, but it just won't catch. It ran
so wonderfully when I parked it last Thursday night, wish I knew what
happened that night!
Chris Mears
Charlottetown, PEI
1988 Volvo 245GL "Daisy"
> If you are looking at the relay installed (BTW, we have the white
> plastic relay in our 1988), but with the cover off, there are two
> coils. The left and the right. When I turn the key in the ignition to
> position three ("on"), this relay clicks. The other relay remains
> motionless and there is no noise from my fuel pump. Being a bit of an
> idiot, I figured what happens if... So carefully inserting a tiny
> screwdriver to close the second relay (the right hand side), I noticed
> that then I could in fact hear the fuel pump merrily whirring away.
> Still the car will not start.
I have a similar problem with an '88 here (it's a parts car, so it's not
a priority to fix). In my case, the left relay clicks in then drops
straight back out when the ignition is turned on. The solution is to
hold the left relay in whilst cranking. Once the engine starts, there
appears to be sufficient power to hold the relay in?!?
Of course, this is a RHD car, so the technique involves sitting in the
driver's seat and lying across the gearshift so that I can just reach
the relay with the left hand while turning the key with the right hand!
I don't know whether the fault is in the relay or in whatever circuit
drives it.
--
Athol
<http://cust.idl.com.au/athol> Linux Registered User # 254000
The state of infrastructure in New South Wales is a disgrace.
I'm a Libran Engineer. I don't argue, I discuss.
Bob
--
The goal when driving is to miss the maximum number of objects.
So looking at the top, and replying in the most simple of terms:
(Described looking at relay with plug at top of unit and relays facing
user)
-Left relay is MAIN and is the on/off for the entire unit.
-Right relay turns fuel pumps on and off, and is dependant on LEFT
being on.
Have I got this?
Thanks
Chris
Yes, but to clarify, the fuel pump part is also dependant on the fuel
control unit receiving pulses from the ignition control unit (i.e.
working ignition, engine rotating) before it will ground the pin that
turns the fuel relay on.
--
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.)
Regards
Per Hauge
"chris mears" <orange...@yahoo.com> skrev i en meddelelse
news:1140404515.1...@g44g2000cwa.googlegroups.com...
Rather than spend countless hours studying the workings of the relay,
take a look at the date stamp on the case. If it's approximately the
same date as the vehicle year then just replace it. In my shop the
symptoms you describe plus the date confirmation would require
replacement of the relay simply for maintenance purposes.
regards
wharf rat in Ashland, Oregon