Fixed - Fuel Pump Not Priming.

[Ams 23 1 Cars]

The problem I'm currently facing is regarding the fuel pump not priming, the engine will turn but will not fire up. I experienced this last year (in this thread - http://forum.205gtidrivers.com/index.php?showtopic=151681&page=1 ) but the fuel pump priming issue went away when I replaced the relay. The car then sat for a few months through winter, then a few months ago I replaced the battery and it fired up instantly. I then sent it to a bodyshop for bodywork repairs and painting. The car has been in the hands of the bodyshop for some time and they reported the car had been starting fine (they had the car for the last few months) but then recently the car started to cut out 20 seconds or so after starting, shortly after the fuel pump completely stopped priming.

 

So far I have:

• Checked the Inertia Switch (now bridged).
• Tried two different Fuel Pump Relays, both verified as working 100% on another GTI6 205 (Dobboys).
• Checked the Fuel Pump Relay socket female connectors (all ok).
• Bridged Pins 5 and 8 which did indeed result in the fuel pump audibly buzz/prime (ruling out fuel pump failure?)

I am stumped as to how the fuel pump primes when I bridge pins 5 and 8 yet it won't prime when I fit either working relays? Dobboy suggested checking the relevant relay pins for 12v readings which I will do tomorrow (the left coloumn of pins of No.40 Engine Management Relay just below) in case there is a broken bit of wiring leading up to the terminal itself:

 

 

 

It's a real kick in the arse seeing as the car is finished and looks great but now it's stuck at the bodyshop! Is it at all possible that there is a bad earth that could cause the fuel pump not to prime? I'm slightly worried the ECU may have somehow locked itself as well. Appreciate any advice.

Edited September 1, 2014 by Ams

[Ryan 99]

The ECU turns on the fuel pump by earthing one side of the relay coil. From the diagram it looks like pin 7 of the ECU and pin 7 of the relay. Check to see if you get an earth there when the pump is supposed to prime.

[Toddy 7]

Check you are getting 12v at pin 14 ( when ignition switched on) which is the switched live from the ignition.

[dobboy 231 2 Cars]

I'm betting on a dodgy joint from the 205 loom to the wire serving Pin14.

 

You should also check the wiring is seated correctly (and fuses ok) in the little dist box near pass headlight, as bonnets been off etc at painters.

 

Also, you said you thought you heard a crackling from front OS in engine compartment, iirc the 16v loom gets powered from the alternator stud, so make sure all is healthy down there too.

 

Take a small mirror and torch with you today, and buy yourself a cheap multimeter from Aldi/Lidl/Maplins.

 

If you've no joy today find out what hours they work and I'll see if I can nip across, I'm sure it will be simple to fault find and fix if I have it in front of me.

 

Also try locate where the jointing of the loom was done, either above pedals, pass footwell, or around NS wing.

 

Good luck today!

[Ams 23 1 Cars]

Will do Dobboy, I really appreciate the help your offering mate. I will check the areas mentioned in this thread and report back. Just heading over to bodyshop now.

[Ams 23 1 Cars]

Just to update, Dobboy was kind enough to pop over and have a look at the wiring on my car (big thanks for that!) Dobboy verified the GTI6/205 aspect of the wiring seems fine. Pin 14 was not showing 12v. So Dobboy linked relay pin 14 directly to the battery and bridged pin 5 and 8 of the same relay to see what happens, the result was the horn/light relay started going like the clappers. This particular relays behaviour reminded me of the exact same issue I had last year that was linked to the alarm system (last sentence in first paragraph followed by pic of the clicking relay: http://forum.205gtidrivers.com/index.php?showtopic=151681&page=1 ). As far as I know this relay clicks as it's meant to flash the lights and activate the horn along as part of the alarm system.

 

I searched for issues regarding the type of alarm I have (a Clifford G-series system) and discovered the siren unit is equipped with an internal backup battery. According to the manual this backup battery exists to ensure the alarm continues to blare in the event of a car thief clipping the mains wire from the horn to the car battery. However Clifford fail to mention that should this external battery inevitably fail it will create the symtpom I'm currently experiencing i.e. fuel pump not priming. To prove this we removed the negative cable from the battery while the alarm was armed, the alarm SHOULD blare, powered by its backup battery, along with the horn/light relay activating (it did this in the past) - however the alarm was silent. I'll be investigating this further and will try and get hold of a Clifford specialist who should have a laptop and cable to connect to the Clifford ECU module.

 

[Miles 331 1 Cars]

Good old Cliffords, a car a mate of mine bought had a silly clifford alarm fitted with a invoice for over a grand, Oddly enough it failed after a couple of weeks of him having it and it was the fuel pump side abit a MI16 engine, No idea what the fault was as we ripped the silly thing out and put it where it should be.

 

The alarm was just over 12 months old too

 

Heaven

Edited September 2, 2014 by Miles

[Ams 23 1 Cars]

Agreed they are notorious, so much so that there are no alarm installers in and around the Glasgow area that I could find that deal with Clifford anymore. However I may have been premature in blaming the Clifford, I got an auto electrician out and told him the checks that have already been carried out. He managed to then quickly trace the problem as originating at the fuse circuit board in the glovebox. It looks like a fizzy drink had spilled on it sometime in the past, the plactic casing appears to have been opened before as sections of it were warped (probably to drain and dry out the fizzy drink) by a previous owner. Here are some pics of it opened:

 

 

 

If a direct feed was applied to the ignition connector on the fuseboard the car started up right away! He cleaned the contacts etc as much as possible but it refused the car refuse to start otherwise. The pin above was also heavily oxidised.I am now sourcing a replacement locally, will know more tomorrow.

[Ams 23 1 Cars]

OK! The problem has now been fixed. The primary ignition feed to the alarm module was not relaying the live feed to the fusebox. So the alarm was indeed at fault as initially suspected but not in the manner I originally thought. The iffy condition of the fusebox still needs to be rectified regardless (replacement arriving tomorrow).

The auto elec managed to retain the functionality of the alarm (immobilisation, locking etc) which was great. He stated one of the internal relays within the alarm ECU module needs replacing. Apparently Cliffords are notorious for it, he mentioned something to do with module location being critical else dry heat affects the board, can't remember what/why specifically but explains why others that have had similar issues (like the bloke Miles mentioned).

Anyway it's fixed and in the process the questionable wiring of the Clifford installer has also been rectified. Many thanks to Dobboy for checking the GTI6 > 205 wiring. At least I know that side of things is all good as well.

[dobboy 231 2 Cars]

Great stuff Ams.... and your car looks great into the bargain.

 

A few adrenalin fueled runs and you'll forget all about the hassle you've had.

 

Sorry about spilling your can of coke BTW......

[Ams 23 1 Cars]

Aye I was proper thirsty as well.

[Spood205gti 0]

On 01/09/2014 at 11:43 PM, Toddy said:

Check you are getting 12v at pin 14 ( when ignition switched on) which is the switched live from the ignition.

Sorry to keep this thread going, but i have no 12v at pin 14 on the fuel relay when the ignition is on. My fuse box also looks like the picture above (like someone has spilt juice or somethibg on it)