injector order wasted spark setup

[bens_cab]

Hi guys

just a quick question im running v3 msns-extra 029q2

its wasted spark so 1&4 and 2&3 whats the best way to wire my injectors
1&4 to bank 1 2&3 to bank2???
or should i be doing this differently does it even matter???

at present i have 1&4 bank1 and 2&3 bank2

[bens_cab]

to add injury to insult ive got a weird over heating petrol thing going on fuel pump screaches and filter is very warm to touch im using the standard k-jet fuel pump accuilator and surge tank with a digifant fuel filter

20vt fuel rail and regulator 20vt fuel pump relay

any ideas

really silly question is if for some stupid reason i got the feed and return pipes on the fuel rail the wrong way round would it run enough not to notice and cause the fuel to heat up

i havnt checked this yet as i think if they were round the wrong way the car wouldnt rev as it does

[keithmac]

Check the in-tank lift pump, if that`s not supplying fuel to the main pump the main pump will overheat and sieze quite quickly..

I don`t really think it matters which channel go to which injector, maybe run 1 and 4 together on channel1 and 2 and 3 on channel2?.(just read this is how it`s wired )

You could check which is fuel feed by removing the pipes from the solid lines in the engine bay and getting a mate to quickly turn the ignition on/off, the prime from the MS would fire the pump, be carefull not to squirt fuel everywhere though!

[bens_cab]

i think it may be the clear plastic box i have near my fuel pump im sure its some kid of recycle catch tank which was standard on late mk1 cabs

that being the case the fuel isnt making it back to the tank but straight back to the pump does that make sense

been thinking hard about this and i 99% sure it has somthing to do with that plastic thingy mk1 hard top golfs didnt have it why ??

[bens_cab]

right found the problem thanks to keith my intank pump isnt getting any power should this be controlled via the relay the same as the main pump

can i just splice the 2 wires together even tho there a different gauge wire
my main pump runs of the fuel pump relay so onlys for 2 secs with ignition then on with crank and run

so basicaly cut into the live 12v supply to the main pump and solder the lift pump live to that

what voltage should they draw just 12v cos ive just put my meter to check and its saying 17v but then it is a cheap crappy meter the batery says 17v too??

[T3Bunny]

On my installs, I run both the main and lift fuel pumps off the relay for the MS.

Its actualy better to wire injectors 1+3 and then 2+4 together. This way its a more even drop across the fuel rail. Less pulsation this way. Since we are not talking about sequential injection, the injectors should be wired up so they cause the most even pressures on the fuel system possible.

[T3Bunny]

Oh, the MK-1 cabbies around 1987 have a WEIRD setup with that plastic tank. The best thing to do is undo your feed line up front, and make SURE its your feed line. Practice safe procedures here of course... If you hook feed and return up wrong... And on these cars the "blow test" will actualy return fuel out of that box and out the return into the tank, either line you blow into.

This setup is a WEIRD combination of the CIS and the Digifant fuel systems. To look up parts in the ETKA you actualy have to pull up BOTH types of fuel systems. Its a surge tank. In theory, because of the way its working, it could heat you fuel up more than normal at its returning fuel into the same tank its sucking fuel from. Its a strange setup for sure. I stared at the first one I saw for quite some time trying to figure out what was going on.

[bens_cab]

so basically i could in theory wire both to the sam point on the fuel pump relay the lift pump itself is only small so was worried about overloading it as its in the tank

[T3Bunny]

Wire both up to your MS fuel pump output. It workes fine. Did you see our old thread on the Vortex?

Yes, I MSed a MK1 cabby not too long ago actually. We had some weird issues because of the confusion the tank caused. DEFINATLY open a line and power it on for a sec and make SURE you got the lines hooked up right up front. We defiantly didn't have them right and it caused some weird issues. I hooked up a gauge to the digi rail and saw it wasn't getting any fuel pressure with the pumps running. The fuel definatly got hot quickly too this way.

[bens_cab]

i pretty sure the lines are on right i took them off to day and blew down the return and could here the fuel entering the tank i tried the same with the feed but couldnt blow down it

also the car does run ok on tickover and i have driven it lighty with auto tune on but gets worse the hotter the fuel gets so im hoping that cos the lift pump isnt powered its causing the main pump to work harder causing more heat

i couldnt believe it when it first fired up i was amazed at how easy it was a 20vt on megasquirt wow just need to do the hard bit now get it running right

[T3Bunny]

What I was saying is with that little plastic tank setup, blowing through the lines won't tell you anything. We did the same thing and it lies because of how the tank works.

But obviously your on the right track if its running at tickover.

Because of the way that tank works, I would eliminate it ESPECIALLY with the turbo setup! What its doing is its returning fuel into that small tank instead of the fuel tank. That tank ALSO feeds the main pump. Only when the engine is returning a lot more fuel does it "overflow" and return fuel to the main gastank. If your lines are still going across the firewall over to the drivers side, its going to REALY REALY exasberate the issue and cook fuel, then feed it right back into the main pump.

Get your lines off the firewall if they are still there. Or at least use a metal sheild and then something like dynomat heat reflecting sheild overtop of it. My turbo has gotten hot enough to cook brake fluid in those lines... I have an 8v turbo setup in my cabby, I imagine yours is even tighter and hotter.

[bens_cab]

yeah the cis fuel tank system is weird i did think about taking that surge tank out and running the return straight to the tank but thought it must be there for a reason?????

the fuel lines run straight up the drivers side (rhd) moved them across when the engine was out so they were away from the fire wall

vw seem to make things as hard as they can god knows why i thougth it would be as simple as feed and return

the car ticks over ok until the fuel heats up then starts to get all funky missing a beat here and there

what was the thread on vortex called

[T3Bunny]

Yeah, VW definatly does some weird stuff... I realy don't see any reason you would HAVE to retain that tank. But also its likely you have simple warmup issues too? What you need to do is to get a quantifiable reading on the fuel temputure to make sure thats actualy an issue. I would get a non-contact lazer temp gun.

You could even perform a simple test and run a hose wil cool water over the feed and return lines and see if it helps any. If it makes a substantial differance, then overheated fuel is your issue.