Centre Console, Air con and Relays

To complete some of the wiring I need to understand where the dash will be and how the centre console will sit. The only issue with this is the dash that comes with the GT4 is relatively basic and wouldn't pass IVA on radius tests alone so will require modifying. also to complete the wiring I need my dials to arrive, which will be in roughly 10 days!

So I've started by making a skeleton for the centre console stretching down the centre. I then sanded the outside edge to give a curved radius which will give me less work to do later.The passenger side is longer to cover more area, the drivers side will require a slightly different piece.

Following that I stretched material around the frame and stapled in place. This provides a skin to frame, I'm now awaiting on the resin to arrive which I will paint on lightly first time so goes hard then a second coat. Following that I will remove the wood where I need  to and then fibre glass the inside for strength. At the point no more will be done until all the required dash pieces are made.

I then decided the relays I'd been putting to the side of the passenger footwell were wired and working correctly for sidelights, headlights and main beam so wanted to protect them. So I found a box used for mini electric circuits and cut the relevant wires for the holes. I then checked the radius on the box and it is 2.5mm so should pass any radius test.

Next I moved on to wiring up the aircon and securing the wires. I studied the wiring diagram and the vintage air system is actually very well explained, I hooked up the battery and ignition wires, followed by the controls and continued to tidy them up.

I wasn't able to test the aircon itself yet as don't have the pipes, however I was able to test the controls and could see the vents move and feel the air coming out, so in principle it all works (hopefully condenser does!) I will be adding a trinary switch which will not only check for high and low pressure switch offs, but prior to the high pressure switch kicking in, on a trinary it can activate a fan to help bring pressure down first (most if not all production cars have this feature)

More electrics and firing the engine up

This week has been a big milestone although not as much in terms of work as I would of liked. So the last intercooler pipe arrived on the Monday ready for a Tuesday evening start so I went and got two gallons of fuel ready.

...It didn't start so I started on testing the basics.

First I checked for a spark - yes but looked weak so I put the battery on charge and put some copper plugs in I had bought.

Now I had a good spark but was unsure on fuel, the MR2 doesn't prime on ignition only once the key is turned to the starting position. So I hooked the fuel pump up differently so it did prime on ignition...No change.

Next was to check the Earths and clean them up, to be honest they all looked clean and good as they were new but I did them again anyway... still not any better.

I started using a multimeter to confirm all the sensors and ECU were within tolerances and getting power, all looked fine. So I posted on an MR2 forum for help and was advised to use the diagnosis port to get the codes out but without the combination cluster I had no engine light to blink. Peter on the forum was helpful and told me the relevant wire to hook up a bulb to and I had my engine light, it flashed out a code of 41... throttle position sensor (TPS) so I set about re-calibrating and adjusting this...still no joy.

A friend then came over and we used a battery booster supporting 900amps... still no joy and not always easy to turn over, we begun to think starter motor so rather then messing about I got one ordered and fitted Saturday morning. still no difference.

tried adjusting the dizzy cap...nothing still

It was at this point I was confident of all my work so decided to whip the cam cover off and the cams appeared to be completely out by 5 / 6 teeth on inlet and same on exhaust but one clockwise out and other anticlockwise.

I never thought to even check here as I had a mechanic do the engine work as I had the head off, unfortunately at the time I was learning a lot about the engine and car so didn't see this mistake being made or feel confident in doing it myself.

I then simply removed the tensioner adjusted the cams, reset the tensioner and fitted it all back together. I put all the inlet parts and intercooler back on and went to start it...fired instantly.

I could only run it for 30 secs as there was no coolant in the system however it started and would rev, the idle was not steady but with the TPS and dizzy cap both being fiddled with and need setting back up, it ran rather well, although loud (no cat or exhaust!).

Since then I've started it twice and it fires instantly.

Now that was sorted I could get back on to the electrics, I have completed the side lights, dipped headlights, horn and Radiator fan.

With all this wiring it was time to start tidying it as I was happy with a number of systems and it was looking messy, so I started to place some in conduit

things become a lot clearer as you move completed systems out the way...however the fusebox area becomes more and more busy all the time.

 I have not bundled in conduit down here yet and have just grouped the wires. On the left hand side of the photo are two relays, one for the side light circuit and one for the dipped headlights, a third will appear for main beam.

As well as getting the above moving along nicely I need to complete the coolant reservoir for the coolant system, so I fitted the filler cap and estimated where I will fit the expansion bottle.

The 3 wires in the photo are for the indicators, sidelights and brake lights, two more wires will appear (reverse and fog) before they are bundled together.

The engine control / wiring, fuel pump, igniter etc... is all exactly the same as the MR2 so should be easy to get assistance if i have any issues to diagnose.

The other circuits, I used the MR2 loom to cut out the wire i wanted and stuck to the same colours as the original MR2, again hopefully making it easier in the future.

Intercooler fitting and more electrics

So first of all, following on from the last update on the 'starting electrics' I had a problem with the starter motor kicking in when the key was turned to the On position, before actually getting to the start position. After 3 hours of tracing backwards, up to the point of the relay then searching online I found out I had missed a key Earth, this earth attaches from the loom under the intake manifold to the intake manifold itself.

This earth can cause many types of weird and wonderful behaviours...don't miss it like I did!!

After that I proceeded to fit the intercooler now the pipes that I had measured arrived, the bracket was designed for an OEM intercooler but I had a more beefy after market one so had to design my own pipework solution and will adapt the brackets. So I ordered various 45 degree bends, reducers and alloy pipes and ended up with the below;

After this it was back to the wiring. The fuseboard I showed installed in the footwell of the passanger side in a previous blog update is the hub to all the electrics outside of starting and charging. so first was to hook up a permanent battery feed to the board (for Hazards) and the ACC switch from the igntion (indicators / lights / Radio etc...)

Once this was done I first completed the column stalk wiring for the washer jet and wiper motor, simply put because this was the easiest and a good test for me. I got this working first time, which is a good start! I also decided on the route the wires would take through the bulk head to get to the front of the car.

Once I had tested the wires (using block connectors temporarily for testing) I then lightly bundled them separately. Shown below from left to right in this photo

Red - Headlights (not wired in yet)
Yellow - Horn
Blue bundle - Wiper motor and Jet
Green Bundle - Indicators
4  seperate leads in choc block - starting wires

The reason I have bundled these separately is for future maintenance although they will be put in a single conduit.

Now I have not had to label any wires, the reason for this is I am using the MR2 original loom for a wire source and stripping it of the required wires and building my own loom, because of this I'm using the same original colour codes meaning once complete the MR2 Electrical Manual will be able to be used for working out what wire is what when required. This should make it easier for any future diagnosis or future owner of course (one day!)

As listed above the front indicators were put in and tested and working correctly, at the same time I tested the hazard switch which worked fine,  although I'm waiting on the 3 pin relay so they just stayed on rather then flashed. The photo below shows the green and blue bundles heading in their relevant directions and the self tapped cable brackets. Remember 300mm maximum spacing for IVA, so its a lot of holes.

Once I was happy everything was working, I then looked to change the choc block with proper automotive connectors, I'm still waiting on water proof connectors to arrive for those areas but I could do the interior connections for the indicators and wipers.

The wire bundles should be quite small under the dash due to my dial cluster solution which will be explained when it arrives soon.

As well as the above I finally fixed the rear fusebox to the chassis and made it secure, there is still more wire securing required down there to be done, but it will be fine until I work out brackets needed.

I also re-bundled the rear lighting harness for the rear clusters and have already run the indicator cables back to them ready to be tested again (in original Mr2 wiring loom colours)

I've found this stage of the wiring easier then I thought I would. The next stage will be the headlights and using the relays and when the one missing intercooler pipe arrives I will attempt to start the engine for the first time in 1yr and 8months!

Electrics and turning over the engine for the first time.

I have managed to complete the electrics for the starting and charging. I managed to get the setup similar to a car OEM setup with alot of safety in the system.

So I removed the high amp fuses from the MR2 these come in a small block so I did not disturb them (or the wiring) and simply used the wires coming off them. This means I have a 120amp from the battery feeding various 80amp / 50amp and 40amp fuses.

At this moment in time I have only concentrated or Ignition and charging so have ignored my secondary board already fitted.

When fitting the 3S-GTE engine the rear engine loom is split in two effectively as the ECU required 3 connections. The engine loom requires no stripping but the other loom also had all the rear lighting wires in it and as Ill be producing my own wiring for that, so it was stripped of the wires.

The number of wires to actually turn the engine over (and hopefully fire it up) is just 6. The image below shows them wired and where the wires came from and what they lead to. the only wire not shown is the very high amp wire direct from battery to starter motor.

So as you can see there are 3 connectors full of wires and only a few required to hopefully run, but don't strip the rest yet there are some other useful wires in there!

After this, all Earths were connected, there are 3 of the engine block / gearbox to the chassis and one in the loom itself. As well as this the fuel pump will require another earth of its own.

At this point various voltmeter tests were done to check the obvious connections.

At this point I unplugged the fuel pump as there is no fuel in there and gave the engine its first crank over

Success...Wont lie, I was pretty happy with myself. Before 3 weeks ago I didn't know what a relay was, how the wiring was done on a car, or what amps mean't and as for a wiring diagram it was just a nice set of lines. I couldn't of completed this though without the PDF file for the MR2 wiring (in colour) as I have had to learn it to some detail.

The next stage is to complete the intercooler piping, once complete I will do a test start up of the engine. Based on how the relays appear to be in series the fact it turned over should mean it will run...however we will have to wait and see.

If that's all successful Ill complete the coolant system overflow and fill it up to leave it running. To be clear the engine is full of oil, Running without coolant for 30seconds wont cause issues...No oil and 30seconds running could be all you'll ever get from that engine!