How2 - Convert from C18NZ SPi to C20NE MPi

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Robsey
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How2 - Convert from C18NZ SPi to C20NE MPi

Post by Robsey »

The Robsey Way - How to convert from 1.8 SPi to 2.0 MPi

Information before you start.

Section 1 - Why change the Engine.
Section 2 - What is Needed
Section 3 - Insurance and DVLA information.
Section 4 - Removing the 1.8 SPi
Section 5 - Fitting the 2.0 MPi
Section 6 - Teething Problems

Section 1 - Why Change the Engine?

There are two main reasons for changing your engine.

a) To replace a faulty /worn / broken engine
b) To get a bit more Ooomph

Anyone who has been reading my very long bizarre Work in Progress thread, will know that I changed my engine, because I was convinced that it was now very old and worn out, The 1.8 lump had done 225,000 miles and I was getting a low engine oil pressure light on the dash at idle when the engine was warm.
Despite top end and bottom end work, I decided that it would not be worth throwing any more money at the old engine to have the crank-shaft, bearings,shell, rings and the various other bolts and seals replaced that would be required to do the job properly.
Approx £350 to £500 in my estimate - more than my battered old Cav was worth!!

So I threw in the towel and opted to get an alternative engine...

Another 1.8 SPi would have been very simple, and could have been done within the day, with the correct equipment.
But there was nothing available at the right time for the right money.

So in the end I shelled out less than 100 notes for a complete 2.0 litre MPi set-up...well almost complete... Total cost was approx £250 including service parts and other spares that became apparent on the way.

Section 2 - What is Needed

This is a rough list of everything that I came across.

1) Electrics.
a) The correct ECU Loom and the Power Loom- Note that these are diferent between manual and auto models.
b) An ECU - Motronic 1.5.Usually Alpha Code GE for C20NE or 20NE.
Most are non-immobiliser units. If yours is a very late Immobilised set-up, then ensure that you have the correct matched key transponder, pick-up ring barrel and immobiliser unit etc.
c) Black Injection / Fuel Pump relay - Different from the purple SPi relay.
d) All the sensors - Crank Angle Sensor (CAS), Coolant Temperature Sensor (CTS)
e) The correct coil - usually Alpha Code WE for the NE engines.
f) The correct Yellow Octane coding plug.

2) The Engine itself
a) A known good engine,
b) starter and matched flywheel or flex-plate as required
c) Get a fresh gasket set for things like manifold gaskets, pump seals etc.
d) The C18NZ alternator, Power steering pump and other ancillary components can be fitted to the C20NE.
e) Clutch Assembly, whilst the engine and box are apart. Check which flywheel you have, as this will affect which pressure plate you need. (Flat or Pot flywheel).

3) The Induction side of things
a) The inlet manifold
b) The throttle body complete with Throttle Position Sensor
c) Idle control Valve
d) Vacuum hoses, breather pipes and brake servo vacuum pipe
e) The correct Intake Pipe (Bigger internal diameter than the SPi set-up)
f) The Air filter housing complete with the Air Flow Meter and filter
g) It is a good idea to get gaskets for the throttle-body and induction manifold components

4) Exhaust side of things
a) manifold with Gaskets, seals etc
b) Correct front pipe with Oxygen / Lambda sensor
(I used the manifold and front pipe from the NZ, I just fitted the multi-wired Lambda sensor into the NZ exhaust manifold in place of the single wire sensor.)

5) Fuel Stuff
a) Multi-Point Fuel Pump
b) Tank vent valve
c) New fuel pipe clamps etc and 8mm bore fuel hose.

6) Equipment / Tools / Misc
a) Engine Crane - Essential due to the weight of an engine.
b) Wide range of sockets and spanners, screwdrivers, etc.
Includes "E" External torx Sockets, Trolley Jack and Axle stands.
c) PVC / Electrical tape and / or Cable-Ties for tidying up looms etc.

7) Chemicals
a) Oil, water, Anti-freeze.
b) RTV or gasket paste.(Blue or grey paste... the red stuff is not as good)
Do not use any paste on the induction side of the engine. - it may get sucked in and block vacuum or fuel flow.
c) Thread Locking paste - Loctite 342 or similar for ALL fixtures that you don't want to work loose.
d) Coppa-Slip for all threads that you may wish to undo later
e) White Petroleum Jelly / Vaseline for all electrical connectors, but you can also use Coppa-Slip.

Section 3 - Insurance and DVLA information.

Please consider the effect of carrying out an engine transplant.

1) The vehicle insurance premiums MAY increase, as engine changes are considered to be too risky for most companies to consider providing cover... that and Alloy wheels.
I just declare the correct engine size when renewing my policies. In my case the prices did not increase compared to the 1.8 prices.

2) If you do have an accident, and it is blatantly obvious that you have not declared the correct engine in your vehicle, then the insurance company will do their best not to pay out.
Your insurance may be declared void - Leading to other potential legal issues.

Insurers will want to know everything about the car that the donor engine came from - Model, year, trim level, auto/manual and so on.

3) The DVLA will need to know that you have changed the engine, however evidence for the purchase of the engine will be required.

Especially if the engine is of a different size.
Do not consider reducing the size of the engine to below 1500cc, as the red-tape / politics is a total ball-ache.

They will wish to know
Engine Capacity (cc) and also the Engine Number.

Declaring / advising of the change of engine details is FREE of charge.

Well that is the boring waffle bit done with... :roll:

Now for what happened...

Section 4 - Removing the 1.8 SPi

I did this in a rather unorthodox method - read on.
c18nz engine.JPG
c18nz engine.JPG (51.82 KiB) Viewed 3523 times
The first thing is to drain the fluids,

That is : -
a) Drain the oil from the sump.
b) Drain the coolant, and then disconnect the hoses from the header tank and matrix stubs.
c) Remove the coolant header tank from the inner wing.
d) Disconnect the fuel lines from the throttle body and plug with an 8mm diameter rod or bolt. (make a note which is inlet and which is return)

Disconnect and remove the air filter housing and all the trunking along with the throttle body "top-hat" cover., vacuum pipe and the hot-air duct tube from the exhaust manifold.

Disconnect the electrics.. There are three connection points.
a) The big Barrel shaped connector in front of the Battery.
In the Haynes manual this is referred to as X5, and supplies electrical current to the starter and also the ignition live to the ECU loom.

b) The heavy red cable on the red battery terminal (mine had a thick black sleeve over it), this supplies battery live to the ignition / fuel pump relay.

c) The main earth tag bolted either to the gearbox end-plate, or in my case, it was held on by one of the top bell-housing to engine block bolts.

Disconnect the ECU loom from the engine, sensors, coil, amplifier, and it's termination connection at the ancillary loom (thick black wire).

Then disconnect the ancillary loom from the starter, coolant sensor (gauges), oil pressure switch (gauges), starter, reverse light switch on the gearbox.

Now the mechanicals....
Jack up the front of the car and sit on axle stands.

Remove the exhaust front pipe (at the cat box flange), and unbolt the exhaust manifold
Drop this out, remove under the front of the car.

Disconnect the hoses from the radiator, and remove the radiator.

Remove the alternator and power steering drive belt

It is about now that you should disconnect your bottom ball joints on the wishbones... this did not happen for me, as despite having 3 different ball joint splitters, none of them would go into the gap between the leg and the wishbone.

So instead I cleared as much as possible from the timing belt end of the engine..

So off came the Alternator complete with steady brackets, power steering pump, alternator drive belt tensioner and crankshaft pulley (not the sprocket).

Now we need to support the engine, and remove the mounting from the timing belt end.

I had to remove all the bolts holding the bell housing to the engine block, so also includes the fly-wheel inspection cover plate (gearbox end of the sump).

There are two dowels that hold the gearbox onto the engine.

I rocked the engine firmly, and then pulled the engine away from the box... there is JUST enough space to clear the out put shaft.

Once clear of the gearbox, I pulled the whole engine toward the front of the car, and then swung the timing belt end rearward.

The engine was then hoisted up, clear of the engine bay using a medical hoist, as found in nursing homes.
twist out.JPG
With the engine bay clear, I was able to clean the bay, replace my clutch release bearing, and also rip-out my fuel lines.

Last thing to remove is the ECU Loom. This requires the driver's kick panel being removed, then unscrew the ECU from the side wall.

Disconnect the ECU plugs (2 on the C18NZ), along with the three small square connectors for the Diagnostics, Road speed signal and the air-con connections where fitted.

Then it is just a matter of withdrawing the whole loom through the bulk head (behind where the coolant header tank was located).

Bye Bye all traces of the C18NZ........ :cry
no engine.JPG
no engine.JPG (46.8 KiB) Viewed 3523 times
next part is the C20NE going in :)
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Robsey
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Re: Converting my C18NZ SPi to C20NE MPi

Post by Robsey »

Section 5 - Fitting the 2.0 MPi

Prior to fitting the C20NE to my car,

It was necessary to reconfigure the wires in the ECU connector plug, as it had come from a Diplomat Auto, and was now to be fitted into my LSi Manual. (A simple matter of swapping pins 21 and 42 in the plug)

I fitted a new rear crankshaft oil seal.
And fitted a new timing belt

Next to be fitted are the flywheel, starter and timing belt tensioner from the C18NZ that I had just removed.

I then bought and a complete new clutch and fitted that ready to go.

I dismantled, cleaned and refitted the whole induction system complete with fresh gaskets.

I fitted fresh fuel lines which had been made for me by sriguy

Now the fun begins !!

I hoisted the engine into the bay, using the reverse of the sequence detailed above.

With the hoist taking the weight of the engine, it was offered up to the clutch bell housing. This was assisted by having the passenger side wheel jacked off the ground - I rotated the road wheel, until the output shaft splines lined up with those in the clutch friction plate.

This allowed the engine to be pushed fully home against the bell housing. Most of the bell housing bolts were tightened so that the dowels were firmly located.

The right hand engine mount was fitted and tightened up per the values in the Haynes manual. (Remembering to thread a brand new alternator drive belt through the mount before it is bolted together.

Next I installed the ECU loom, and the ancillary power loom, whilst I could see around the back of the engine...

The loom was threaded into the cabin area, and the gromet / seal was pushed home securely.
ecu loom hole.JPG
The ignition live feed from the C18NZ ancillary loom, and the ECU loom from the C20NE would not connect, as they both had male connectors.
I used the Ancillary loom connector from the C20NE . A matter of removing the NZ male connector and fitting the NE female connector in it's place.
c20ne x5.JPG
I then fitted the rear plumbing - hoses from the matrix stubs and the big plastic pipe across the back of the engine.
Then fit the coolant bottle and the rear hoses .

Then it is a matter of fitting all the parts to the timing belt end of the engine...

That is: - (In this order)

Aletrnator drive belt tensioner
Power steering pump
Crankshaft pulley (not sprocket)
Then the alternator and the new drive belt.

Fit the radiator and connect up the three hoses and the electrical fan thermo switch.

Then fit the air-box and air-flow meter assembly, and connect the loom.

Fit the exhaust manifold and front down-pipe - I used the same parts that were fitted to the NZ.

Note - the Oxy sensor should be fitted to the front pipe on the NE, but it is situated in the manifiold on the NZ.

Fit the multi-wire oxygen sensor in the NZ manifold, in place of the single wire sensor already fitted.
c20ne oxy.JPG
Fit a fresh oil filter, fill with fresh 10w40 oil, and refill the coolant system as required.

Now then as I was going from SPi to MPi - It is necessary to fit an MPi fuel pump and fuel pump relay.

After ironing out a few technical issues, I was then able to start and run the car - yay...job done.
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Robsey
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Location: East Manchester

Re: Converting my C18NZ SPi to C20NE MPi

Post by Robsey »

So here is my poor C18NZ, now being stripped for compatible spares.
hoisted nz.JPG
hoisted nz.JPG (65.02 KiB) Viewed 3521 times
Here is the big connector plug for the C20NE / 20NE ECU
ecu plug.JPG
ecu plug.JPG (133.94 KiB) Viewed 3519 times
Section 6 - Teething Problems

As said there were a few teething problems, which can easily be confusing..

Initially I got a flash code for no rpm signal from the crank angle sensor, however this happened to be due insufficient current and voltage from the battery.

Problems also arose due to insufficient fuel pressure, however this was due to two things..

1) At that point I hadn't fitted the MPi fuel pump.

2) Insufficient fuel in the tank.

Finally, I had a rough idle due to an induction leak... albeit very tiny... this was due to a gasket not being changed between the throttle body and the manifold body.

This post was written approx 2 months after work was completed, and the Cav now runs fine, although the idle is just a little low.

Was it worth doing - Hell yes!!

A total new lease of life in the old girl - it is amazing what 25 extra horses can feel like.

So just for a final list of information,
Here are the Diagnostic Flash Codes for the C20NE (Motronic 1.5)

ALDL Plug (10 pin Diagnostic)

•A - Ground
•B - Engine ECU
•C - Automatic Gearbox (except models with traction control)
•D - Fuel Computer (not UK models)
•E - Engine ECU
•F - +12v (fused)
•G - Bi directional data line
•H - Alarm
•J - 4x4 or Traction Control (pin may not be present on certain models)
•K - ABS



12 Diagnosis initiation/separator (indicates beginning/end of fault code list)
13 Oxygen sensor - open circuit
14 Coolant temperature sensor - voltage low
15 Coolant temperature sensor - voltage high
16 Knock signal circuit - no voltage change
17 Knock signal circuit 2 - no voltage change (V6 models only)
18 Knock control module (ECU)
19 Incorrect RPM signal (Crankshaft sensor - incorrect signal)
21 Throttle position sensor - voltage high
22 Throttle position sensor - voltage low
23 Knock sensor - out of range
24 Speed sensor (MPH)
25 Injector 1 - voltage high
26 Injector 2 - voltage high
27 Injector 3 - voltage high
28 Injector 4 - voltage high
29 Injector 5 - voltage high/ Fuel pump relay voltage low (non-V6 models)
30 Injector 6 - voltage high (V6 models only)
31 No engine RPM signal (engine not running, or no Crankshaft sensor signal)
32 Fuel pump relay - voltage high
33 MAP sensor - voltage high
34 MAP sensor - voltage low
35 Idle air control valve stepper motor (no idle speed control)
38 Oxygen sensor - voltage low (weak mixture)
39 Oxygen sensor - voltage high (rich mixture)
41 1 gear indent switch - voltage low
42 1 gear indent switch - voltage high
43 EGR system
44 Oxygen circuit - voltage low (weak mixture)
45 Oxygen circuit - voltage high (rich mixture)
47 Linear EGR position
48 Battery - voltage low
49 Battery - voltage high
51 ECU memory failure
52 Check engine light - voltage high
53 Fuel pump relay - voltage low
54 Fuel pump relay - voltage high
55 ECU faulty
56 Idle air control valve - voltage low/high
57 Idle air control valve - voltage high/low
61 Fuel tank vent valve - voltage low
62 Fuel tank vent valve - voltage high
63 EST line coil cylinders 2 & 3 - voltage low
64 EST line coil cylinders 1 & 4 - voltage low
65 Idle CO potentiometer - voltage low
66 Idle CO potentiometer - voltage high
67 Idle position switch - voltage low (idle position switch not opening)
69 Intake air temperature sensor - voltage low
71 Intake air temperature sensor - voltage high
72 Full position switch - voltage high
73 Air flow sensor - voltage low
74 Air flow sensor -voltage high
75 Torque control - voltage low
76 Torque control - continuous
79 Full load inhibitor - voltage low (traction control signal)
81 Injector valve 1 - voltage low
82 Injector valve 2 - voltage low
83 Injector valve 3 - voltage low
84 Injector valve 4 - voltage low
85 Injector valve 5 - voltage low (V6 models only)
86 Injector valve 6 - voltage low (V6 models only)
87 A/C cut-off relay - voltage low
88 A/C cut-off relay - voltage high
92 Camshaft sensor failure
93 Hall sensor - voltage low
94 Hall sensor - voltage high
95 Hot start valve - voltage low
96 Hot start valve - voltage high
97 Ignition/Injection cut off - voltage high (traction control signal)
113 Boost control out of range (turbo models only)
114 Boost pressure (idle) above upper limit (turbo models only)
115 Boost pressure (full) below upper limit (turbo models only)
116 Boost pressure (full above upper limit (turbo models only)
117 Wastegate valve - voltage low (turbo models only)
118 Wastegate valve - voltage high (turbo models only)
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Robsey
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Location: East Manchester

Re: How2 - Convert from C18NZ SPi to C20NE MPi

Post by Robsey »

UPDATE -
ECU pin out for the standard C20NE / 20NE ECU.

Typical ECU Alpha Code is GE or similar
Firmware is M1.5 and M1.5.2 for later vehicles.

Here are the pin outs.

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