Back down to earth

Ah well, I was almost right...

Went out for a long, 300 mile day trip to Cheddar Gorge with SKCC. The weather was supposed to be good and it was in patches; unfortunately, between those patches were torrential downpours!

A nice 7am start, and all started well - a good 80 mile thrash to the first coffee/petrol stop, nice chinwag with the others, then on our way again. Dark clouds loomed and there followed a series of 60 second monsoons. After the first couple, I decided to put my roof up, whereupon the rain stopped and the sun came out. Thinking it was clearing, I took my roof off and, yup, you guessed it; grey clouds, dark clouds, rain. During the day, I took my roof on and off about 5 times and only once did I time it right to save a soaking!!

Still, some great roads and reasonable traffic made it enjoyable - until my misfire returned!!!! Arrrgggghhhhhhhh!!!!

Initially, it was very gentle, just a slight hesitation, and I thought that might just be down to not having recalibrated the TPS after I replaced it but it got worse and worse, finally returning to pre-TPS replacement levels.

About 100 miles from home, I stopped and wiggled lots of wires, pushed injectors etc on and VOILA - no misfire for the rest of my return trip. So I'm returning to that perennial bugbear of mine - butt connectors instead of soldered wires. The wire to my TPS, I recall (need to confirm), has a load of butt connectors (I had to extend the wires because they weren't long enough) and I think one or more of them are just about in the connector but, after a bit of time vibrating, they are hanging by a thread - the same issue I had with my ignition wiring, which have been fine since I soldered them.

So, moral of the story: do NOT use butt connectors, they are cr*p!! Well, maybe they're OK if there is some technique for using them that I don't know but otherwise, steer clear.

Of course, this may be another false dawn but it worked for my ignition wiring which have been fine for months now, so it's time for the soldering iron on the TPS wiring. I'll let you know how it goes...

A soggy-looking picture of us at Cheddar Gorge (it wasn't actually raining, which you can tell because I have my roof up!!):

So most of the run was good fun, especially the last 100 miles after I fixed the misfire - I just set my sat-nav to 'scenic' route and followed it part of the way, until I recognised where I was. I took a route that is normally very busy but I must have just timed it right because it had a few cars as target practice but the rest was lovely and clear and when Zedster is running smoothly, he is a blast.

Wonders? Ceasing? Nope!

Unbelievably, replacing the TPS sensor has worked! OK, just a quick 5 mile drive but no sign of my misfire - I am a bona-fide mechanical genius! 

It amazes me that this sensor can have this problem and annoying that my previous research never brought it up as an issue. Only now, when I looked up TPS senor, I found a page that showed symptoms of TPS failure which matched exactly what I had.

So hopefully fixed just in time for a long day trip on Sunday to Somerset and then should be ready for the Alps in 4 weeks or so....

Oh yeah, wiggling the wire for my temp sensor kicked the gauge into life as well... 

Speech Therapy

So Zedster has started stuttering again - time for therapy...

Last time this happened, I improved the security of the coil pack plug and that seemed to fix the problem - until now. So I decided to make it even better - the cable to the coil pack has always been pretty tight, so I convinced myself that was the problem and decided to try get some slack into the system.

I cut off the existing plug, bought a new one with wires already fitted, dug out the soldering iron for the wires, more holes in the bracket I made previously for another cable tie and voila!

Before                                                                         After

Looks much better, less stress on the plug - good, huh? No. Made no difference - back to square one.

I have previously replaced all the HT leads, spark plugs and coil pack so it seemed unlikely to be them. To be sure, I took all the plugs out, checked them for any obvious problems - all fine. Checked the resistance of the HT leads - all seem reasonable.

The next step was to try use the Emerald datalogger software. I have tried this before and, to be frank, without experience, it never really helped but I'd run out of other ideas.

So out for a short run and, amazingly, I may have found something:

That yellow trace is the throttle position and that is what happens when my misfire occurs - it should be a nice, straight yellow line (purple is RPM) but it's spiking down - either the TPS sensor is kaput or my wiring is. The ECU is getting a signal to say I'm taking my foot off the pedal, so it shuts off the fuel but then, milliseconds later, it gets a full signal again and pumps a load of fuel in. Because it is reacting so quickly, I get the stuttering/misfire effect. Sounds plausible?

To be honest, I suspect my wiring more than the sensor but as it is fairly cheap and simple to replace, I've ordered a new sensor. If I'm right, I'm a fricking genius!!

While mucking about, I've broken the connection to my temperature gauge (wonderful) and I also have the dread of my first ever MOT in the next few months and I have a few issues:

1. My horn isn't working.
2. My high beam isn't working.
3. My reverse light isn't working.

The first 2 are wiring issues (who'd have guessed?!) and the reverse light is a physical problem; the cheap light unit has always had a defect meaning the bulb doesn't get held in place well and keeps dropping out. I've got a cunning plan to fix that...

And my Alps trip may be back on!! German/Australian guy checked with immigration and they said he would be OK to cross borders and France has dropped it's quarantine rules (I think -  the wording is a bit ambiguous), so we'll make a call nearer the time.

In, out, shake it all about

IN - Great run out today.
OUT - My misfire is back!!!

Had another 6am start for a run with the SKCC club and it was a doozer...about 20 cars turned up at the start point in Edenbridge, 8 of them Elise's. There were 2 different runs that had been arranged separately - the Elise's and a couple of kits went off one way, we went the other.

A great run, much less bumpy than last week, some great roads, not too much traffic. I was near the back, right behind a snorting Caterham 620R which kept flying off and I could only just keep in sight but HUGE fun. The advantage of following someone faster than you is you realise how much quicker you can go, in particular, how quick Zedster will go round corners.

I was having great fun until about an hour in and my misfire reared it's ugly head again. I stopped to try fix it, assuming it was the same coil plug problem I had last time. The plug did seem to be not seated right and after pushing it back in, it was ok for a while but it must have worked loose again as the misfire returned for the rest of the run and my journey home.

The endpoint of the run was a fisheries (Hawkhurst?) - also there was another Lotus 7s car club, so there were about 20 kits in total - and 6 or 7 Porsche 911s turned up shortly after us - a petrolheads delight:

My trip back was marred by the misfire, although there were a few brief moments of smooth fun.

I think the problem is that the wire to the coil plug is only just long enough - it needs some slack to stop the vibrations loosening the plug. I'm going to work on that...

Sadly, my Alps trip this year is definitely off - my German benefactor is actually Australian and because Australia won't let anyone into Australia, no-one in Europe will let an Australian into their country. Its amazing that governments can be so childish but there ya go...will just have to wait for next year.

Clouds are forming....

The rattle I mentioned last time doesn't seem to be the tensioner - I took it off and it seems pretty quiet, unless it is only slightly on the way out and rattles when under tension? Very worrying...next step is to run the engine (briefly) with the belt off, so I can rule out the tensioner, water pump, driveshaft and alternator as the source.

A minor job was to try cut-down on the irritating buzz from the gearstick. Above 50mph or so, it vibrates with a high-pitched wail which I normally prevent by just resting a finger against it. It's nothing new (thankfully) but it would be nice to stop it happening. My genius idea was to hack an old mouse mat apart and fit it under the gearstick surround, with a vague H-shape in it, the idea being that the rubbery material would do what my finger does, stopping the rattle.

This was what it looked like (excuse the weird shape of my gearstick surround - I had to 'fettle' it when I first made it to allow 1st gear to be selected):

 


It is an improvement but still rattles at motorway speeds - ah well. This is a common issue with the GBS quick shift and a possible fix others have done is to replace the rod-end for a better quality item. Personally, I can't see that is the problem but the part only costs £16 so worth a shot at some point in the near future.


I've also got a new throttle cable to consider fitting (and it's at least good to have a spare), again in the future.

Had a great drive out today with the SKCC - weather lovely although the 6am start was painful for me. We had a lot of rain the night before, so there were a lot of damp roads and a couple of rear-end slides pulling out of shaded junctions - quite fun, actually:

The route included some very bumpy roads and I really thumped the bottom of Zedster a few times - sounded horrendous but hopefully no long-term damage. I looked at my seat bolts a few weeks ago and they're worn down to the nut now!

Still hoping to do my Alps trip (now July 20th), providing France cancels it's quarantine policy.