Mono Motronic Injection into MK I

[Peter Jones]

As the title says, I'm about to attempt to graft the mono motronic injection from a '96 Cordoba into a MK I.

The MK I already has a SEAT 1800 in it that was previously injected. It also started life a a diesel so it has the dual fuel lines and the diesel tank.

I also have a complete, running Seat donor car for the injection system.

If anyone has attempted this before I'd love to hear about it, specifically,

1 Fuel Pump / Tank.
The pump appears to be in the Tank on the SEAT. Should I attempt to mount the entire tank into the MK I or use a different kind of external pump and which kind?

2 Immobiliser
The donor car has the chip in the key style of immobiliser. Is there an easy way to disable the system? I'm open to just installing it and making it work with the MK I ignition, fiddly be looks do-able. Last choice option is just to tape the SEAT key to the immobiliser sensor and jam it all up under the dash never to be seen again.

3. Which bits of the pollution gear are essential? I'll put as much of it as I can back in there but I don't know if it's all going to fit!

4. I'll be unravelling the wiring loom and removing the unrelated bits before re-looming it again properly. Anything I should watch out for?


By the time I'm finished this Mk I will have the following SEAT running gear.
Motor (already in)
Injection/ignition.
Tank?
rear brakes
radiator and fans (already in)
Seat belts. (Rear retractors in front with stalks off SEAT seats.)
5speed gear box (not looking forward to linkages!)
Anything else that fits!

Pete

[shaneth]

Sounds like you are in for a fun time Peter. Look forward to reading more about the build.

[h100vw]

The pump appears to be in the Tank on the SEAT. Should I attempt to mount the entire tank into the MK I or use a different kind of external pump and which kind?
++++++++++++++++++++++++++++++++++++++++++++++++++ +
MK1 GTI type set up with external to tank pump would work I reckon. No need for the accumulator though. I have a mk2 digifant pump in the shed which would be upto the job for your application.
++++++++++++++++++++++++++++++++++++++++++++
2 Immobiliser
The donor car has the chip in the key style of immobiliser. Is there an easy way to disable the system? I'm open to just installing it and making it work with the MK I ignition, fiddly be looks do-able. Last choice option is just to tape the SEAT key to the immobiliser sensor and jam it all up under the dash never to be seen again.

+++++++++++++++++++++++++++++++++++++++++++++++++
Just fit the full loom and tape the key to the pick up coil.
++++++++++++++++++++++++++++++++++++++++++++++++++ ++

3. Which bits of the pollution gear are essential? I'll put as much of it as I can back in there but I don't know if it's all going to fit!

++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++
I think that would depend on what legislation you need to meet. Personally, I'd bin it and plug any spare pipes up.
++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++

4. I'll be unravelling the wiring loom and removing the unrelated bits before re-looming it again properly. Anything I should watch out for?

++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++
The engine loom should be independent to the lights and stuff so I wouldn't expect much will need removing. I would fit it and any spare stuff, I'd just cut the plugs off and tape them into the loom. Removing stuff can be time consuming and of little benefit to the finished article. I know cos I am in Avionics and spend my life doing it. ;(
++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++

By the time I'm finished this Mk I will have the following SEAT running gear.
Motor (already in)
Injection/ignition.
Tank?
rear brakes
radiator and fans (already in)
Seat belts. (Rear retractors in front with stalks off SEAT seats.)
5speed gear box (not looking forward to linkages!)

++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++
If you have a 4 speed donor then you only need a couple of 5 speed bits to make that work.
++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++


Anything else that fits!

Pete

I have done a few conversions in my time. 16V MK1s/MK2s G60s working stuff out isn't that hard with the right manuals.

Gavin

[Golf Loon]

Yeah Gavin is right about the fuel pump. The eletric one you are using atm might even be upto the job as it doesnt need high pressure like kjet.

Theres not many extra bits in the loom, blinkers, wiper and fan control. Just chop em and tape em in.

I reckon there is probably only a few wires to actually power up the ecu.

Pickup coil with the chip glued to it is an easy fix too.

Keep us posted, sounds like a good conversion, car will be very efficient on fuel.

[Peter Jones]

Any ideas on the actual specs of the fuel pump? The one I've got in there at the moment is a Facet, it can probably hit 8 PSI or so, I had to put in a regulator set to 3.5 psi to stop it forcing fuel past the needle and seat.

The Facet is also a pulsed pump rather than the more constant flow of the rotary style pumps. Any thoughts?

The radiator looks good in there. I've got to bring accross the variable speed wiring yet, I'm using the MK 1 wiring to drive it at the moment.

I'll pop up some pictures soon, it was a pretty tight fit! I've still got to make up some air baffles yet.

Pete

[h100vw]

Any ideas on the actual specs of the fuel pump? The one I've got in there at the moment is a Facet, it can probably hit 8 PSI or so, I had to put in a regulator set to 3.5 psi to stop it forcing fuel past the needle and seat.

The Facet is also a pulsed pump rather than the more constant flow of the rotary style pumps. Any thoughts?

The radiator looks good in there. I've got to bring accross the variable speed wiring yet, I'm using the MK 1 wiring to drive it at the moment.

I'll pop up some pictures soon, it was a pretty tight fit! I've still got to make up some air baffles yet.

Pete

An electronic injector will need around 50PSI mate, so it ain't never going to run off 8PSI.

The pump I have is the std one off a digifant GTI which was running well when the engine was replaced for a 16V. The 16V has Kjet which requires a higher pressure to operate than digifant so the pump had to be replaced too.

It has a built in fuel filter in the housing too.

Gavin

[Peter Jones]

I've been google-ing away all night and I've tracked down the numbers.

The normal operating range for mono-motronic is 0.8 -1.2 Bar which equates to 11.6 - 17.4 psi.

The best Facet solid state pump will only will do 7-10 psi.

Still quite low pressure for injection but not as low as carby. I guess it works ok because the injector sits above the throttle valve.

SO we were all sort of headed in roughly the right direction. I suppose a higher pressure pump would just make the regulator work harder.

Does anyone know if the SEAT tank will just fit in the MK I?

Some of the early SEATs had two pumps, a lift pump and a inline pump, perhaps I could just use the inline version. Anyone?

Thanks for all the comments.

Pete

[h100vw]

Peter, please post your source, that seems mega low to me.

Cheers
Gavin

[Peter Jones]

I'd heard that these were very low pressure systems. I'm still looking for more info. I suppose i could borrow a gauge and test it if I get the time.

Here's where I found the info, looks like a scanned workshop manual.

http://wheels.vc.org.ua/petrunko/volks/1081-04d.pdf

Thanks for your interest, I'm sure we'll nut this thing out.


Pete

[h100vw]

Good find, something new to me.

If you can only get 8PSI from the facet, I reckon it'll run proper weak.

Don't forget that pressure and flow are 2 different things. Just getting to 1.2 BAR without adequate volume will not do.

Need to know the pressure an volume. Something like 2 litres a minute or something like that. There are specs for a MK1 GTI along those lines. Picked that as it's the only one I ever had cause to check.

Gavin