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Hello,
I've finally found the time to put Frenchy back on the road after a 4 yr hibernation in a carcoon.
She started fine and ticked over lovely about two months ago, but recently I needed to replace the fuel pump that stopped turning.
Heard it priming, but then the engine would only run for about 10 seconds.
Occasionally turning key to start caused a "click" (some relay?) and complete power failure, which recovered after some deep breathing downtime!
Frenchy hasn't moved yet, and more recently, even after 2 new accessory and an RPM/fuel relays, the instrument cluster now has no power, and the fuel pump now can't be heard to
prime, so the engine just happily cranks away with no firing!
No fuses blown, incl no.10! Weird...
Any troubleshooting thoughts to point me in the right direction would be sooo helpful please?
(my intention is just to able to drive her out of her carcoon, flatbed her to Chris in Canvey Island for a well deserved thorough going over after her rest!)
Thanks all,
Mat
#3866
DOC 100 Vin#3866 Ashington, West Sussex
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Sounds like you have to pay most attention to the MAIN and ACCESSORY relays. Have you knocked the connection plugs to them? Have you disturbed them in any way? Have you put the correct plug on the correct relay between the two if you've had them disconnected?
Following circuits is normally the first path of understanding any break down in function.
Fuel pump requires the following routed connections to be in place: MAIN relay with ignition ON, fuse #1, fuse #7, RPM relay, fuel pump, inertia switch, grounds.
The binnacle requires the following routed connections to be in place for basic power: MAIN relay with ignition ON, fuse#5, grounds.
Rissy
(Forum Member 288)
(DOC Member 663)
May 1981 vin#1458 "LEX"
Grey, Flapped, Black
Chassis: #1073
Engine: #2839
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2005 BMW M3 in Velvet Blue
2010 Honda Civic Type R in Sapphire Blue (1 of 115 made)
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Have you been messing around under/near the instrument binnacle? could you have activated the inertia switch and stopped your fuel pump working?
Posts: 64
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(21 Jul 2022, 07:28)Rissy Wrote: Hello! Thanks very much for the reply - it sounds like i have some interesting investigation work to be getting on! Out comes the multimeter! I'll let you know how I get on..
I have some spare time during next week so I'm hoping to get on top of it...
The relays seem identical (recently bought from DeloreanGo) but will check their connections again, and maybe swap em back with the old ones to rule them in or out as a troubleshooting exercise...
Thanks again... Mat
Sounds like you have to pay most attention to the MAIN and ACCESSORY relays. Have you knocked the connection plugs to them? Have you disturbed them in any way? Have you put the correct plug on the correct relay between the two if you've had them disconnected?
Following circuits is normally the first path of understanding any break down in function.
Fuel pump requires the following routed connections to be in place: MAIN relay with ignition ON, fuse #1, fuse #7, RPM relay, fuel pump, inertia switch, grounds.
The binnacle requires the following routed connections to be in place for basic power: MAIN relay with ignition ON, fuse#5, grounds.
(21 Jul 2022, 18:38)Chris Williams Wrote: Have you been messing around under/near the instrument binnacle? could you have activated the inertia switch and stopped your fuel pump working?
Hi Chris,
Thanks for your reply...
I had checked the position of the inertia switch popup, but will properly investigate whether my clumsy foot has pulled a wire!
Gotta get the multimeter out and do some investigating...typical Delorean, bless her, but fun!
Cheers,
Mat
DOC 100 Vin#3866 Ashington, West Sussex
Posts: 64
Threads: 22
Joined: Jul 2006
Things move slowly with Frenchy!
So, once upon a time, you could hear the fuel pump priming before starting.
I shorted pins 30/87 on the RPM relay which forces the fuel pump to run, so that's good news and the inertia switch works okay when activated.
(Didn't try starting the engine in this config.?)
I have tried both my new and old RPM fuel pump relays and no joy starting. (maybe both dodgy?)
Haven't yet swapped back the MAIN and ACCESSORY relays to troubleshoot.
All Relay pins and plugs look good in my humble opinion!
(Still yet to troubleshoot the no power to binnacle/fuel gauges etc, apart from back lighting when headlight switch is on.)
DOC 100 Vin#3866 Ashington, West Sussex
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Quote:I shorted pins 30/87 on the RPM relay which forces the fuel pump to run, so that's good news and the inertia switch works okay when activated.
(Didn't try starting the engine in this config.?)
Would have been no issues trying to start it like this. Give it a go.
Posts: 64
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(29 Sep 2022, 20:15)Chris Williams Wrote: Quote:I shorted pins 30/87 on the RPM relay which forces the fuel pump to run, so that's good news and the inertia switch works okay when activated.
(Didn't try starting the engine in this config.?)
Would have been no issues trying to start it like this. Give it a go.
Will do! Thanks for the go ahead!
DOC 100 Vin#3866 Ashington, West Sussex
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Hello again,
Some good news; after some fiddling around with the relays I had replaced I embarrassingly found human error was to blame! I could've kicked myself quite hard!
Anyway, so the engine runs, but sits very high at about 2600 to 3000 rpm. Any pressure on the throttle causes a brief rise but then kills the engine if foot left there!
I'll do some forum digging coz I believe this issue isn't new the Delorean but it is to me & poor old Frenchy. Her engine has been 100% since 2004, so left sitting around for awhile, she's rebelling!!
Any help in the meantime, many many thanks... Mat
DOC #100
VIN 3866
DOC 100 Vin#3866 Ashington, West Sussex
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Quote:Some good news; after some fiddling around with the relays I had replaced I embarrassingly found human error was to blame! I could've kicked myself quite hard!
Cant leave it like that without fessing up!
The more clean/fresh fuel is run through the better. Having sat for so long there will no doubt be varnish/gum etc in various places. I do have some commercial injection cleaner that i use that works well to clear it.
Posts: 64
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Joined: Jul 2006
(20 Oct 2022, 19:34)Chris Williams Wrote: Quote:Some good news; after some fiddling around with the relays I had replaced I embarrassingly found human error was to blame! I could've kicked myself quite hard!
Cant leave it like that without fessing up!
The more clean/fresh fuel is run through the better. Having sat for so long there will no doubt be varnish/gum etc in various places. I do have some commercial injection cleaner that i use that works well to clear it.
Crumbs I can't believe how time flies...
Had another play with her today and the same as before - she sits very high at about 3000rpm and any mention of my foot approaching the accelerator shuts her down!
(okay, the embarrassing human error as mentioned above was fiddling around with the relays & not plugging one of the arms back in properly… Such a common problem that we hear and know about from the forums, but I still went ahead and did it myself!!)
DOC 100 Vin#3866 Ashington, West Sussex
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