fuel pump doesnt prime when ignition is turned on

[MattDon]

so i got a mile down the road and the engine cuts out and wont restart, did a paper clip test & its the infamous 41 code, is it normal to be imobilised by this fault? i have a hall sensor at home but am affraid to mess up the timing. anyone have any suggestions?

[muley]

Sorry to hear you are having a problem.

If the sensor is fitted in roughly the same place as the old one it should work - we've seen Elans with the timing way out and they will run - you can always refine the timing later.

Jim

[MattDon]

aa bloke thought it might be the fuel pump that was stopping me from going, aparrently there was no fuel going through the injectors when i was cranking it and i couldnt hear the fuel pump fire up when i turned the ignition, still have to get the cas sorted as i still have the 41 code, not been a good day for my car. got to say cant fault the AA i almost feel guilty that im moving to a break down service offered cheaply by the insurance company.

i am right in thinking the fuel pump sits practicaly on top of the fuel tank and apart from all the trim is pretty easy to get to?

[rip]

Are you sure you've not tripped your fuel pump's inertia switch? It's the push button switch next to the battery.

I wouldn't worry about upsetting your timing. That's an easy fix & your Elan may run a lot better with it set to a value other than 16btdc anyway. Mine certainly does!

[Monty]

Even with the 41 code you should get home on limp mode

Is there a fuse for the fuel pump?

[RayD]

...

[MattDon]

i think the inertia switch is behind the passanger side rear speaker enclosure, we did check that out. thanks for the diagram ray, i was asked where the fuse was but there are so many all over the place..... i think.

Will checkout the fuse and the wiring for the pump hopefully get that sorted and then fit the hall effect sensor. sounds easyish until i realise its the coldest winter so far in..... a long time and my garage is full of part stripped elan, i realy didnt thnk this through.

[matts1972]

I wouldn't worry about upsetting your timing. That's an easy fix & your Elan may run a lot better with it set to a value other than 16btdc anyway. Mine certainly does!

Sorry to be a bit off topic here, but how did you find a better timing than 16btdc? Did just try different settings (this would seem a bit cumbersome to me), or is there a way to approach the perfect timing in one go?
Cheers,
Matthias

[rip]

Sorry to be a bit off topic here, but how did you find a better timing than 16btdc? Did just try different settings (this would seem a bit cumbersome to me)

Yes, at 16btdc, mine ran poorly. I couldn't even feel the turbo doing anything, overboost was achieved at 4100rpm, the exhaust was sooty as hell & overrun was common.
I found a flat, straight, quiet bit of dual carriageway & did a times 30-70 in 4th (or was it 3rd, I can't really remember). I used Elanscan to check for knock.
I almost halved the 30-70 time.

[MattDon]

checked the fuse, and theres still no life, inertia switch has been throughly fiddled with, if thats the one by the passanger side speaker enclosure on an S2. i hear a click from that area which sounds like its related to the fuel pump, because the pump (normaly) comes on for a few seconds upon tuning the key then stop and im pretty sure the click is related to the stopping of the pump as the timing is just right. this is looking like its the pump but i havnt managed to check if theres voltage across it yet, as i remember its a real pain getting in under there. actualy im not sure what im asking because im going to have to bite the bullet either way.

oh unless there is an easier way to make sure the fuel pump is getting power?

[DeeAitch]

checked the fuse, and theres still no life, inertia switch has been throughly fiddled with, if thats the one by the passanger side speaker enclosure on an S2. i hear a click from that area which sounds like its related to the fuel pump, because the pump (normaly) comes on for a few seconds upon tuning the key then stop and im pretty sure the click is related to the stopping of the pump as the timing is just right. this is looking like its the pump but i havnt managed to check if theres voltage across it yet, as i remember its a real pain getting in under there. actualy im not sure what im asking because im going to have to bite the bullet either way.

oh unless there is an easier way to make sure the fuel pump is getting power?

Worth checking the relay to see if is getting power from the ECM (terminal 1) as well as the Inertia switch (terminal 3) - not sure about the S2 but on RHD SE's both of these are in the battery compartment.
The ECM needs to see an engine crank signal before it will allow the pump to run - that's why the pump normally stops after a few seconds when you switch the ignition on but don't crank the engine.

[MattDon]

so does than mean if there is something wrong with the engine crank signal then the pump wont spin after the first stage of ignition? the reaon i ask is because im not sure where the engine crank signal comes from but it sounds like it could be something to do with the CAS which ive been having problems with. Realy dont want to have to replace the fuel pump to find out it not the issue.

will dig around the manuals to find those terminals and to double check the location of the inertia switch.

[DeeAitch]

so does than mean if there is something wrong with the engine crank signal then the pump wont spin after the first stage of ignition? the reaon i ask is because im not sure where the engine crank signal comes from but it sounds like it could be something to do with the CAS which ive been having problems with. Realy dont want to have to replace the fuel pump to find out it not the issue.

will dig around the manuals to find those terminals and to double check the location of the inertia switch.

It gets its signal from the ignition module but I guess that must get something from the CAS?
See EMK2 page 8 & 9

[MattDon]

ok so ive got to what i thought was the fuel pump but that turned out to be the fuel filter and i finaly managed to find the fuel system section in the manual, turns out its in the fuel tank, oh the joy!!! ive checked and there is power across the fuse in the foot well, and theres still the click that im pretty sure is the pump being told to stop pumping when turning the ignition on. Ive also had a good look and the inertia switch is where i thought and all seems well there. Ive not got the emj/emk or eml handy and i'll try to dig out my E-versions as i suspect i havnt printed them out.

But this is looking like a roof stowage compartment floor removal which is a job and ive never managed to get everything out without damage.

will find EMK before i do anymore im hoping theres an eaier way to check the fuel pump in there.

[lotusnut]

You could also see if you get 12v at terminal 5 of the fuel pump relay when you first turn the ign on. You should have 12v at terminal 3 and I think 5v at terminal 1, terminal 2 is earthed. If nothing at terminal 5 when ign first turned on, poss relay fault. To confirm relay fault, fit a fused jump wire across terminals 3 and 5 and try and start the car. If it starts, needs a relay.

[MattDon]

hello im back, been mad busy but got a chance to look at the car today....

with the ignition on at the fuel pump relay i get terminal 1 0v terminal 2 0v terminal 3 1.5-2v terminal 5 0v
within the first 2 seconds of ignition i get 11v 0v 1.5-2v 0v

i tried to bridge 3 and 5 but made no difference, so im looking at the inertia switch thinking 1.5-2v seems abit low and it might have a problem, but i dont have a replacment as its a different design to the SE version, and i cant get a contact to it to check of voltage, i tried bridging that too but it didnt seem to help but i dont know if i got a good connection.

im also showing 1.5-2v on the white and green wire ontop of the fuel tank, and battery voltage to the sender, using the earth on the tank top so im assuming thats good.

if i dont get any suggestions i may just try to wire up the old fuel pump from the se and see if that pumps. but its at work so cant do it today, oooh should i try putting 12v direct to the pump to see if that makes it work? could nick the input from the sender and listen...

[wayne]

Hi Matt

Sorry to read about the problems your having.


After having fuel pump problems a good few years ago...and code 41 problems recently (The code 41 turned out to be a bad ECU. Car would start when cold, run like crap occasionally quit altogether when warm)! Looking at montys suguestion about the limp home mode. maybe problems are not related. You are welcome to borrow my duff ECU to see if it will start. or maybe someone closer could offer you a loan of one if you think this may be a problem it will start my car runs normally sor a few seconds and then gives a CEL?


Fuel pump problems was car quit whilst under full throttle and would not restart... the occasional cough. From what I am reading in your posts. I think I went along a similar route, checking fuse, voltages at relay, inertia switch, etc... Voltages still didn't seem right and still not convinced so pulled the fuel pump from the car and wired it up in a bucket of water... It worked but pumped with very little pressure.(nothing like 50psi)!

I replaced the pump with a locally found varient.. I think it was from an oldsmobile £30 instead of £250 for 1 from Lotus. I had to solder wires as connector differed slightly, other than this the pump looked identical.

As far as I know it has worked fine for years except I had to upgrade fuse... I seem to remembering it recomended a higher value than the origional and the origional blew after several months.

If your problem is a fuel pump. as you said you can hear a click... (probably a relay, mine is a LHD SE but my inertia switch is behind the speaker and I seem to remember the relay being in the same place. sorry no wireing diagram in front of me at the moment.. I hope I will be corrected if wrong)

My first suguestion would be after turning the ignition key after not using the car and fuel pressure in the rail being 0, can you hear the pump run??? (and not just a click)

I never really noticed mine running when I first turned the ignition untill I sorted out the problem... I'ts not loud but it's audable... (well in my car it is but there again it's not an origional pump and it's the only elan I know)!

I probably have a spare pump... but at the moment it's in an unknown condition and for what the last one cost I think if I was going to go through the hassle of replacing it. I would stick a new one in...

Although the worst job for me was removing the fuel line connectors on top of the tank. other than this there's a few of the plastic Scrivets to remove which tended to round off, but if you already have access to the fuel pump then I believe these these are already removed.

If it's looking like the pump and you can't find one locally let me know and I'll see what I can do.

Hope this helps

Wayne

[MattDon]

hi wayne thanks for all the advice and your kind offers, no the pump does not pump when the ignition is on and i just tried to wire it direct from the sender wire with no luck, i do have a second complete fuel tank so i'll try wiring it up to check first and if it spins then i'll swap the whole lot over (the internals not the tanks) once i crack this is a hall effect sensor then we should be all good.

[MattDon]

update. direct 12v to pump does work, so im back to being confussed, could it be the inertia switch or something between that and the A3 fuse? im trying to work out where the voltage drop comes from someone did say 5v is normal at terminal 3 of the fuel relay, what drops that after A3 fuse? and why am i showing 1.5-2v or is that down to my flatish battery? and if thats normal whats going wrong? ive tried a different relay with no luck.

[wayne]

Hope U get it sorted matt..... some people have better luck getting the fuel pipes off than others...

Before you splash out on a new HES. Is your CAs using an origional HES? If so I have one here that I believe is good.

I replaced it due to the same error code, first I had one of our avionics guys test it and resolder all connections and then still had same problem. (New ECU fixed the problem)!

I ended up chopping wireing loom to fit new style HES....

Sorry I do not want to part with it ( I will buy an Elan whenever i return to live in the uk)! but you are welcome to borrow it if needed (to be returned to a uk address....).

Just a thought to help you chopping wires...!