Cold - Pissed Off - Fuel Pump not Priming.. any Good Ideas?
Discussion
Typical, I park the Chimaera against the hedge on the far side of the drive 8 days ago, and today is won't work and I need to move the car out of the way. 
Getting the obvious things out of the way - the battery is fully charged, everything was working perfectly well before parking, and yes it does have petrol in it.
Basically it all works, the engine will crank over, but the fuel pump has not "primed" first so the fuel rail is not pressurised, therefore won't start. (By priming I mean the funny buzzy squirty noise before cranking the engine)
So far:
Replaced the Fuel Pump relay - I can hear it clicking too on turning the ignition on, so thats not the problem.
Replaced the 20A Fuse (Fuse 13, 97-97 layout) - It wasn't blown anyway but as I had one I swapped out out as well as giving the fuseboard some WD40.
Got under the car and cleaned and WD40'd all the connections to the Fuel Pump.
Yet to try:
Volt meter at the Fuel Pump connections - trying to de-frost my fingers before that one.
...?
Anyone got any really good ideas before I continue the thankless "hunt the mystery problem" game..
Many thanks,
Matt.
Getting the obvious things out of the way - the battery is fully charged, everything was working perfectly well before parking, and yes it does have petrol in it.
Basically it all works, the engine will crank over, but the fuel pump has not "primed" first so the fuel rail is not pressurised, therefore won't start. (By priming I mean the funny buzzy squirty noise before cranking the engine)
So far:
Replaced the Fuel Pump relay - I can hear it clicking too on turning the ignition on, so thats not the problem.
Replaced the 20A Fuse (Fuse 13, 97-97 layout) - It wasn't blown anyway but as I had one I swapped out out as well as giving the fuseboard some WD40.
Got under the car and cleaned and WD40'd all the connections to the Fuel Pump.
Yet to try:
Volt meter at the Fuel Pump connections - trying to de-frost my fingers before that one.
...?
Anyone got any really good ideas before I continue the thankless "hunt the mystery problem" game..
Many thanks,
Matt.
M@H said:
Is there !? I'll have a look...
Would the realy still be clicking if this was blown
Cheers,
Matt.
Cant remeber if my relay was clicking, i think it was because it took me a while to check these fuses...there are two of them each in its own holder lose with the relays.
My engine was turning over, lights and everything was working but no fuel pump...replaced this fuse and it has been fine ever since...it went through a phaase of blowing them every other day...twisted the next new fuse slightly and crimpped the connector a bit and it has been fine ever since.
There are two circuits through the relay (one for the coil that operates the relay, one for the power switched by the relay) and they are fused separately. If you heat the relay clicking it suggests that the fuse for the contgrol circuit is OK, but you still need to check the other one. If this is a problem that you *have* to investigate on the coldest day of the year then that would be worth checking. If it was me I'd just hotwire the fuel pump and get the car to somewhere more pleasant to work on it.
GreenV8S said:
There are two circuits through the relay (one for the coil that operates the relay, one for the power switched by the relay) and they are fused separately. If you heat the relay clicking it suggests that the fuse for the contgrol circuit is OK, but you still need to check the other one.
Thanks Pete, much appreciated GreenV8S said:
If this is a problem that you *have* to investigate on the coldest day of the year then that would be worth checking. If it was me I'd just hotwire the fuel pump and get the car to somewhere more pleasant to work on it.
Ahh you're on of those lucky people with somewhere for the car that is more pleasant than the driveway 
It may be cold but its not raining, which is worse still 
Edited by M@H on Wednesday 24th January 15:57
Short across the relay terminals, the ones that are the input from the loom and the one that goes to the pump. The clicking does not necessarily mean that the relay is passing current. If the there is current to the pump but it is not turning it could be a bad earth for the pump, quite possible is this damp weather, or the pump is u/s. The 944 ones just used to stop working for fun. I have a spare if it is an externally mounted one it may fit. I think they ran at about 36 psi
The crash cut-out switch under the passenger side dashboard? Undo the elastic pocket (2 screws) then open the access panel. Don't know why it should trip, but it's another thing in the power circuit which goes ecu-relays-cutout-connector-pump. The connector is one of those multi-way things under the access panel behind the passenger door. If you hot-wire power to each point in turn you can isolate the problem area.
Ian.
Ian.
lwt said:
The crash cut-out switch under the passenger side dashboard?
That's worth a look. Being a 1997 car though, it should have a warning light to say it's tripped. Left of the speedo, has an "i" symbol on it.
M@H, are you sure it's the fuel relay that's clicking? I wouldn't want you to think it's ok, only to check everything else and then find that it's not.
Mine has the same problem but intermitent usually when the car has been left a while.
There are two relays of the same type on the same part of the loose wiring loom (lays on top of the battery). when it first happened I swaped them over and it worked but the plug in imobiliser fob stopped working (I had to use the remote). I think I now have one intermitant relay (always clicks, does not always work) and one broken one (does not click).
I have never really got to the bottom of what the problem is. I bought a couple of aftermarket relays but these do not work at all (Buz when you turn the ignition off). I guess I need to buy the Bosch one - quite expensive I am told.
The problem with this occaisional fault is that it is difficult to fault find.
Last time it happened I turned the ignition on and off about 30 times and when just about to give up it sparked into life. It was dark and cold so no opportunity to get the multi meter out.
This fault has showed up and disappeared half a dozen times in the last 2 years. However, it has always worked in the end and has not left me stranded. yet.....
Be interested to know what your fault is. I need to cough up for new relays and see if the fault occurs again.
Matt
There are two relays of the same type on the same part of the loose wiring loom (lays on top of the battery). when it first happened I swaped them over and it worked but the plug in imobiliser fob stopped working (I had to use the remote). I think I now have one intermitant relay (always clicks, does not always work) and one broken one (does not click).
I have never really got to the bottom of what the problem is. I bought a couple of aftermarket relays but these do not work at all (Buz when you turn the ignition off). I guess I need to buy the Bosch one - quite expensive I am told.
The problem with this occaisional fault is that it is difficult to fault find.
Last time it happened I turned the ignition on and off about 30 times and when just about to give up it sparked into life. It was dark and cold so no opportunity to get the multi meter out.
This fault has showed up and disappeared half a dozen times in the last 2 years. However, it has always worked in the end and has not left me stranded. yet.....
Be interested to know what your fault is. I need to cough up for new relays and see if the fault occurs again.
Matt
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