MOT with a broken engine

The past week or two has been mostly spent trying to understand the various engine issues.

Firstly, after noticing the quantity of smoke produced, and the appearance of some white-yellow mayonnaise-ish looking gunk under the oil filler, I tried a quick compression test, with alarming results.

Expected range for this engine is 142-156 psi (when hot). I couldn't easily get the engine hot without driving it, so I did it cold / warm, and ended up with values between 35 (cold, dry) - 90 (warm, wet [i.e. with a drop of oil in the cylinder]). This was pretty inconclusive, but:

• cylinder 2 looks a bit lower than the others, indicating head gasket issues or liner wear
• all these numbers are very low

Other issues: the car is, or has been running, very rich, hence the smoke.

However, after discussions with Will and others, I've come to the conclusion that there are no symptoms directly attributable to the low compression, so I am inclined to ignore this until I find otherwise, as the fixes are either expensive (head gasket) or very expensive (liner wear = new engine).

We plugged the car into the laptop, and using that and a multimeter, decided that the MAF (airflow sensor) was probably not working, which would explain the richness. Will tried hooking up a pot in place of the MAF and twiddling it by hand to achieve a good idle, and we found that the car would stall when it was twiddled too far, proving that the ECU is indeed using a reading from the MAF. So it was duly replaced with a second-hand MAF off Ebay (new ones are £200, hence the preference for a £20 second-hand one).

However, results with the new MAF are not very clear. The car runs much the same, and again the laptop does not show a change in airflow when I blip the throttle. However:

• wiring between ECU and MAF has been tested and found good
• The signal coming off the MAF is in the right range and responds to throttle blips

Tonight I tried hooking up a pot in place of the MAF again, and seeing what the laptop had to say. It turns out that the laptop still didn't display useful data, even though the car would once again stall if I twiddled it too far - the obvious conclusion being that the software isn't displaying a correct value.

So, the way forward seems to be to assume that the MAF is working OK, that the over-fueling is a thing of the past, and see what happens at MOT on Saturday. The emissions tests will hopefully tell me some useful things. It might even pass.

Longer term, I doubt that the engine is in good shape given the compression numbers, but I guess I can always look for an M3 engine when my bank account is a little healthier - I suspect the engine will probably run for now.

First drive

Lots of progress on various things this weekend. Saturday was mostly electrical: sorting out the reverse light wiring, and extending the wires on the lambda sensors. Unfortunately it turns out that they use solder-defying wire, so I had to use two sets of bullet connectors to insert an extra section of wire, which was a bit tedious, but should work fine.

While I was at it, I got annoyed with the ECU reporting an error for the missing fuel vapour valve (on a proper car, it takes fuel vapour from the tank and feeds it into the air intake when getting a perfect air/fuel mix isn't critical [i.e., part throttle with a warm engine]). I don't have this facility on my car, so I removed the valve. Since the ECU complained, I measured the resistance of the valve, which was about 42 ohms, and stuck in the closest resistor I could find instead (200 ohms), which seemed to keep the ECU happy.

Today was mainly spent working on the bonnet. Emily helped me fine tune the shape, after which we attached the bonnet clips. I'm not completely happy with the fit, but I think it's about as good as we're going to get without cutting a new bonnet from scratch from a fresh aluminium panel.

The plan was then to drive out onto the drive and set up the geometry, but it was a bit dark, so in the end we just tidied the garage and drove back in again. Still, first drive: it went well, although there was a fair bit of smoke from the engine. Will suggests that it may be too rich, caused by faulty air or coolant temperature senors, or maybe just the lambda sensors not being warmed up. Need to try and figure out what's going on here or it will likely fail MOT. Fingers crossed it's not burning oil because of fatal engine issues...

I let Emily drive the car back into the garage. Happily, she didn't crash.

http://www.youtube.com/watch?v=srfQgUFF-ps

Emily, not crashing or speeding. Phew.

The road to Hell

... is paved, they say, with good intentions, and so it proved for me over the weekend.

It started well: it looked like some bits for attaching the clutch switch weren't going to turn up on time, but I was rudely awakened on Saturday by a knock at the door, which turned out to be the postman with the clutch switch. Glad I got up to answer it then.

Plumbing it in was relatively painless, surprisingly - I cut the braided clutch hose, following Peter's advice to use side-cutters, and then switching to a hacksaw when they proved ineffective (the hacksaw worked much better, though I recommend wrapping the hose in tape first to prevent fraying), and attached new end pieces to the cut ends, which, as they have not leaked so far, seem to be good. I cable-tied the switch into place (more on this later), and set about bleeding the clutch.

This went surprisingly badly: despite the reservoir having plenty of fluid in, nothing was coming through. In the end I gave up for the day.

On Sunday, Will came over and had a poke around the car for me. He pointed out that the gearbox switch was clearly going to fail IVA, because it caused the wires to rub against a panel, so after some deliberation we decided to chop the switch down with a hacksaw. Despite very limited access, we were mostly successful, although some work still remains to be done to insulate the wires which now occasionally touch and randomly light the reverse light.

He also pointed out that I could do a better job of mounting the clutch switch. This was clearly true, so with the best intentions, we made up a bracket to mount it onto, and tried to attach it. At this point I snapped off a bolt in the block and after much cursing, was unable to remove it.

Will left me to it at this point, but undeterred, I made up a new bracket which conveniently covered up the mess I'd made with the previous attempt, and got the clutch switch mounted in a much more satisfactory way.

Clutch switch bracket (attempt no. 2). Note cross-threaded banjo bolt.

Whilst tidying up, I noticed that the clutch hose was now a little twisted. Once again with good intentions, I detached it from the master cylinder, rotated the end by 180 to remove the kink, and reattached it... at which point I cross-threaded the bolt and damaged the thread in the master cylinder.

This evening, then, was spent removing the master cylinder to get decent access to it, running a tap down it, and reattaching it. Fortunately the repair process was painless and after a couple of hours, I had everything back in place, with the clutch properly bled, and the switch functioning properly.

Now that I no longer need access to this part of the car, I permanently fixed on the drivers-side front wing, and then the exhaust. It's looking very nearly ready for an MOT...

Nearly ready for MOT?

Edit: props to Emily for her brainwave when it came to fitting the exhaust. (Using a jack to raise the manifold up slightly made it a lot easier to get it on).

Panels and exhaust

After some delays, my replacement primary and the silencer arrived in the post. With Emily packed off to Germany for the weekend, I spent it almost entirely in the garage working on the car.

Exciting parcel.

First up, I fitted the new primary - this one clears everything with plenty of space. With that attached, I put on the manifold, and trial fitted the silencer.

Silencer on.

It's pretty big (8" diameter), but it has twin cats which are good for 300 bhp, so there's plenty of headroom for future engine upgrades. Most importantly, the sound is great: not too quiet, not too loud, with a nice growly sound at idle and a really sporty noise when I poke the throttle a bit.

Once the exhaust mounts were in, I was finally able to bolt down the driver's seat, and attach the rear wheel arch and drivers-side wing.

Saturday's main goal was to run the engine, now that I had a silencer to keep from upsetting the neighbours, and see if everything worked as it came up to temperature. I gave it about 10-15 minutes, during which time the radiator got warm, and no leaks developed, or anything else untoward, other than the Racelogic traction control reading the revs about 50% too high. A bit of internet research suggests that it is probably configured for a 4-cylinder engine, which would make sense, so this will likely be an easy fix. I also tweaked the switches on the dash so that they light up dimly with the sidelights, and brightly when in use.

On Sunday I enlarged and finalised the hole for the exhaust primaries in the front wing; then Rich came round to help have a look at the bonnet. He spent most of the afternoon having a nap in the drivers seat, but eventually he woke up and we got round to lining up the bonnet and bending it. Conveniently, the exhaust is about the right radius to bend it over.

Bonnet on. Looking really close to being complete now...

Unfortunately, the bonnet predates a design change where Peter moved to having flared front wings, to allow hot air to vent at the sides of the engine bay. This means that the rear end of the bonnet needs to come out about 15mm further each side... which I think is the cause of the 10mm vertical gap to the wings. It would be possible to flatten out the lip at the bottom and rebend it, but I can't imagine the result would be very pretty, so I think the best solution will be to get a new, slightly bigger bonnet.

There are a few things left to do before I get an MOT and IVA test, but not many. I need to fit a clutch switch for the traction control to do its full-thottle-gearshift magic (not an IVA requirement, obviously, but access is much easier before I rivet on the drivers-side front wing); cover up some sharp edges with rubber trim; fit the fourth wheel-speed sensor; sort out the bonnet; setup the suspension geometry... and that's more or less it.

I'm tempted to book an MOT a long way away, as (I believe) I can legally drive to it, but this is probably unwise. Tempting though.

Traction control progress

Some progress here: three out of four sensors are mounted in the uprights, and appear to be giving sensible readings, though I won't really know for sure until I've calibrated the system properly. At any rate, when I turn the wheel, the current output by the sensor varies, and is detected by the traction control box, so I'll assume that's working for now.

Traction control switch mounted.

The control unit is now mounted. Not totally sure if this is secure enough from thieves (it's currently stuck on to a bracket with velcro); I might have to fix it a bit more permanently. It looks good though, and some fiddling reveals that the previous owner bought all the upgrades, so I can do full-throttle shifting once I get a clutch switch installed. This should be easy, it's just a hydraulic switch on a T-piece mounted on the clutch hose.

Also: I asked Racelogic about the upgrade screen issue - they got back to me with a solution within hours on a Sunday. Can't complain about that.

Budget: blown

The original intention was to fit traction control, but as the car progressed and my bank account got smaller, I had decided to shelve this for a future project. However, I was unable to resist a (relatively) cheap Ebay auction, so I spent today fitting the Racelogic traction control system and trying hard not to think about my overdraft.

Despite some worrying communications from the Ebay seller (paraphrasing, me: "does it come with all connectors, wires etc"; him: "what are wires?"), it turned up with all the connectors and many metres of wires. As the only space on my bulkhead was right under the dash, all of the wires needed to be trimmed down substantially, so most of the day was spent soldering.

A few niggles arose: the "you are about to reverse park in a hedge" light is switched earth, as opposed to the dashboard lights, which are switched live, so driving the ABS light in the instrument cluster from the traction control will require me sorting out some sort of relay. Also, there seems to be a software issue with the unit itself - when turned on, instead of going into the normal mode, it goes into firmware-flash mode and prints "Waiting for Upgrader" until I twiddle the controls a bit. Probably need to contact Racelogic and find out what's going on here.

Lots of wiring remains to be done; there is the small matter of hooking into the fuel injectors and fitting sensors at each wheel, but the important part is to get the under-dash stuff done so I can bolt the scuttle in.

Exhaust progress (part 2)

Lots of exhaust progress today. I started out by replacing the Elise exhaust mounting bushes, which had worn through and were letting the exhaust rattle around. Much fiddling later, I then started work on the seven.

I'd been putting off cutting out the hole for the exhaust for a while, mainly because it offered lots of potential for awful mistakes. I started by making a template which would fit around the exhaust primaries:

Exhaust template.

In the process of doing this, I noticed that one of the primaries was actually touching the chassis. It looks like this will have to go back to the exhaust people for adjustment, which is a pain as it will probably delay completing the car. Hitting it with a hammer would probably work but would look pretty shoddy, and it would be a shame to make a mess of the shiny exhaust.

Exhaust primary touching chassis (nearest tube touches the diagonal rail)

Leaving that for now, I got on with nibbling out a hole in the panel:

Starting to make an exhaust shaped hole.

As expected, the panel wasn't as bendy as the template, so considerable enlargement was required before it would fit:

Embiggened hole.

Finally, it fit. The final result is pretty good, though the spacing around the edge is rather variable. This was inevitable really, as the panel needs to slide over the primaries into place. There's more space than I would like on the right, and a few places (top middle, left edge) which probably need filing back 5mm or so.