Out with the old, in with the, old? And thank you tiny Japanese hands.

So last Wednesday the clutch slipped on the Mazda. I’d already ordered a replacement one ready for when the engine comes out but decided to do it now before the long drive this week. What a shitter of a job! Got it up in the air nicely Wednesday night and its oil draining (which was black!) then Thursday I attacked it. The book says to remove the PPF, exhaust, slave cylinder and remove. For those who don’t know, there’s a large girder underneath the car which bolts the differential and gearbox together – they call it the power plant frame (PPF). The bolts holding it together are tightened to 89lb, but these were a lot tighter, and seized! I didn’t think any of the parts had been replaced before but maybe they had, or maybe using cadmium plated steel bolts in aluminium wasn’t a good idea by them.

I’d also had another problem with the car since Monday night when I left the pub. It was odd, the charge light came on but the headlights stayed bright. I had two choices, stay in the unlit pub car park freezing and wait for recovery or see what happens on the way home. 20 miles later the charge light went out. This was the same Tuesday and Wednesday so I did a bit of meter reading and decided that it was coming on when the alternator was putting over 16 volts into the car, meaning the alternator must be duff. So whilst it was up in the air I did some Google searches to find it’s over £200 for a new one! Bollocks to that, I found a “tested” one in Milton Keynes for £30, bargain. So as I left my dad to wrestle with a stuck bolt I shot off and collected it. He could be a good contact as he’s an MX5 breaker, however, keep reading…

I supported the engine off a block and tackle on the RSJ in the garage rood. Out comes the propsaft, off comes the PPF, now for the gearbox. Or maybe not. These bolts which are meant to be around 40lb (from memory, could be 50lb) was just as tight as the PPF. This is why a suspect it may have been fiddled with before. And amazingly, one of the bolts was so buggered it damaged the thread in the engine as it was removed. The more I was working on this car the more I was realising how small Japanese people are. You need seven joints in each finger to reach a lot of these bolts. Something which necessitated the need to remove the coil pack, held in by a bolt in quite possibly the worst position ever conceived. With that eventually removed it was time to call it a day. I had to go into college in the evening and everyone was dying from exhaustion.

The next day whilst waiting for help to arrive I decided to replace the alternator. As it turns out this is an easy job, when the car isn’t three feet in the air and when the under-tray is removed! After removing it, and cursing as I couldn’t get the bolt back to put the new one in I removed the under-tray and it was a piece of piss. Of course that’s ignoring the bolts which broke when removing the tray… Help arrives, the remaining bolts get removed, the gearbox stays where it is. It’s bloody heavy and it was getting caught on the exhaust I still refused to remove. No way was I touching exhaust bolts which may be been there for 23 years! It also didn’t help that the clutch slave cylinder hadn’t been removed… I didn’t read that part in the manual until then! The exhaust had (note, had) some insulation on it in terms of fibreglass wrapped in metal and its lip was catching on the bell housing. With some effort and careful twisting the gearbox was eventually out. With it on the ground the slave was removed as when the car was up in the air it was noticed to be leaking and a replacement ordered. And the exhaust insulation was hacked off!

The clutch was fecked. Down to its rivets and burnt. I’m happy I replaced it now as between last Friday when it was put back on the road and next Wednesday when it’ll be having its engine removed it will have clocked up near 700 miles. I get around… So now it was time to put the gearbox back, sans slave cylinder. Again, a rubbish job. It wouldn’t go into the hole for it in the body work as it was still hitting the exhaust. A rest with the gearbox on my stomach and another assessment and I spotted how to get it up there. Funny how you can struggle for ages then get a clear thought which makes it all fall into place! Then as Haynes says, refit was the reverse of removal.

When all was said and done and after maybe 16 hours the clutch, slave and alternator had been replaced. Except it wasn’t that simple. Now there was a new fault when the engine was hunting, hesitating when driven and generally crap. Saturday I got my multimeter out and checked over the O2 sensor, throttle position sensor, air flow meter and timing. All seemed fine and there were no error codes. I checked the charging circuit and it was putting in 17v, just the same as the older alternator… I also noticed that the charge light was dim with ignition on and with the engine running the light pulsed. Hmm… I wonder if it’s the alternator. This is when I found out it was far easier to replace with the car on the ground. What do you know, it fixed it! And, the charge light fault seems to have been cured, for now. Bloody thing!

Oh, and amongst all this mayhem I found out my 2010 fuel hose on the Herald had perished and was pissing fuel everywhere.

cheeky postie

So there I am working in the garage when the postman walks up and calls me a traitor! When I ask why he jokes that I’ve defected by buying a Japanese car. Cue five minute conversation of my plans and him recalling when he owned a 948 as his first car.

Wen I bought the Mazda I wasn’t given an old MOT but was told it had a short one and I haven’t received the V5C yet so couldn’t check when the MOT run out. The one before the current one expired 18/03/2013 so I thought it was going to end around now and seeing as I want to change a few things on the engine and prove its reliability to myself I booked it in to my normal station and made the half mile trip. By the way, don’t these heat up quickly. Over 6lt of water in the system and it was already putting out warm air when I arrived. Give him my keys, he brings it into the workshop to warm up and logs into the MOT computer. Short story short, it’s got over a months MOT left on it! He tells me to stop apologising and doesn’t charge me as he gets 5-7 cars a years to test from us.

Ok, onto more useful progress. All of my other time yesterday was spent getting the fibreglass bonnet on. A bit of advice for anyone thinking of getting one – they fit like shit and don’t buy a used one. I have no idea who made the holes in this one for the hoop or catches but Stevie Wonder could have done a better job. It’s too long in some places, too short in others, the material is too thick meaning it doesn’t sit on the bulkhead properly and the catches don’t sit correctly, the apertures for the headlight bowls are too small and… I’ll stop whining. It’s on and I just need to get the o/s lights fitted before a bit of de-rusting to some brackets and glassing in of others.

Yes, it fits like shit. But at least it won’t rust!

Japanese spaghetti

After Fridays cock up and hassle yesterday was far easier. To be fair something I did went wrong when removing the immobiliser but it was odd it somehow fixed itself. Removing it was simple, except for the extra complications. So the next days task was to remove the Mazda branded alarm. I was a little worried about this as it should have been wired into everything, and it was! The interior lights, boot, petrol flap, glove box, doors, bonnet and the SS Marine Sulphur Queen were all attached to the black box of magic and sorcery. Sorry, boxes. In reality, it was a piece of piss! The only awkward part was re-soldering where it split into the coil wire. Other than that it was just a case of carefully ripping wires out.

I also made myself a little diagnostic jobby. Well, it seemed like an essential tool after the last faff! I’ll copy and paste and link back to where I found the info so you all can read it. Plus of course include my photos of it.

Today I’m going to remove the Herald bonnet and try to fix on the fibreglass one. It’s not finished, has no lights etc. but it feels like I need to get it on to be motivated right now.

Written by Fletcher Blades. Note that this may not work for models newer than 1995 (OBD-II))

So, what’s up with your engine? Is your engine playing up? Want to know what’s wrong with it? Well now you can find out what’s wrong with your engine, or, at least what the Engine Control Unit (ECU) thinks is wrong with it, which should lead you a good way down the path to correct diagnosis…

The MX-5’s ECU continuously monitors many of the parameters related to engine performance such as fuel, spark, air, RPM, etc. It uses this information to get the most performance and fuel economy possible from the engine. A nice side effect is that it can detect many problems your engine may be experiencing and it even has a way to tell you about them. You may have read in Miata Magazine about reading off the error codes on the check engine light on the dash-board, but our MX-5’s and Eunos Roadsters don’t have this light. Due to a bit of detective work by Glenn Stephens in England, we can now report to you how to make an indicator so you can read these error codes yourself, without having to bother your friendly local Mazda technician with his expensive special service tools.

You will need a Light Emitting Diode (LED) and a resistor. These can be purchased at Dick Smith Electronics, Jaycar or any other similar electronic hobbyist supplier for spare change – less than $2. You’ll also need a separate short length of wire. (An unpainted paper clip will do) If you buy a red coloured LED, you will need a 2000 Ohm resistor, or any other colour will need a 500 Ohm resistor. (If you happen to already have a selection of resistors, any value within about +/ – 25% of these will do). Simply solder one lead of the resistor to one lead of the LED. It doesn’t matter which side of the diode you put the resistor on, but it will pay to take note of which is the longer of the two leads on the diode, as this will determine how you plug it into the car.

The finished product is shown in the picture – it’s that simple! Now, locate the Diagnostic Connector in the engine bay. It’s a small black box about the size of a packet of matches, near the top of the passenger’s side (Right hand drive MX5s) shock absorber, also near the engine air inlet snorkel (and it has Diagnostic stamped on it!). After you unlatch the cover, there should be a label inside explaining what the different terminals are called. With the ignition off, use the short piece of wire (or paperclip) to connect the TEN terminal to one of the several GND terminals. Now, connect the indicator between terminals B+ and FEN, with whichever side of the diode had the long lead towards B+ (If you get it the wrong way around, no damage will be done, you’ll just get no light out of it)

Now turn on the ignition, but don’t start the engine. The LED will light up for about five seconds (assuming you got it the right way round) before it starts flashing out the error codes (if there are any). This will give you a chance to get around to where you can see the indicator. Count the number of flashes to indicate the malfunction code. If the code is a two-digit number, the tens digit will be displayed first with a long flash, then after a 1.6-second dark pause, the ones digit will be displayed with shorter flashes. If there are multiple codes, they will each be separated by a four-second pause and may include two-digit codes, so pay attention. (For example, one long flash followed by three short flashes would be a code of 13) The codes will repeat after four seconds so don’t worry if you miss them the first time. Take as long as you need to record the codes and then refer to the Fault Codes chart shown.

Keep in mind that the indicated device may not be faulty itself, but may have a bad electrical connection, or some other fault may be making it have an abnormal signal. The fault codes are stored by the ECU indefinitely, so after you’ve done something to cure the problem, you need to clear the codes by disconnecting the car battery for a minute or so. This will wipe the computer of its error codes. Now you can drive the car again for a while, and re-check to make sure the error code hasn’t come back. (If you didn’t clear the ECU’s memory, it will still have the old codes.) Hopefully, as several others and I have been able to, you’ll be able to use this information to find the cause of whatever’s wrong with your car. However, I do know one car that runs poorly, but has no fault codes, so its not a complete solution, but it should help the home mechanic (or any mechanic without Mazda’s diagnostic gear) get a better idea what any fault may or may-not be. I hope you’ll only need to use this info to satisfy your curiosity rather than from necessity.

Code
Meaning
1
Ignition pulse
2
Ne signal
3
G signal
4
SGT signal (1.8L)
8
Airflow meter
9
Water thermistor
10
Intake air thermistor in airflow meter
12
Throttle position sensor
14
Atmospheric pressure sensor
15
Oxygen sensor (output too low)
16
EGR function sensor (1.8L)
17
Oxygen sensor (output not changing)
25
PRC solenoid valve (1.8L)
26
Solenoid valve (Evaporative canister purge)
27
EGR solenoid valve (vacuum)(1.8L)
28
EGR solenoid valve (vent)(1.8L)
34
34 Idle air control (1.8L)
36
Idle speed control valve