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Shant Fabricatorian
21st October 2004, 11:48 PM
Coming home today in driving rain on the freeway, the spluttering started (naturally, it was in a concrete canyon with no room to pull off), then a few seconds later, fortunately once out of the single-lane canyon, it coughed and died. Take it from me, getting across four lanes of uphill gradient freeway onto the left-most lane (no hard shoulder) with no power sounds a lot more fun than it actually is. Did I mention there was spray and speeding trucks just to make things interesting?

Got it across ok, but I didn't have a clue what to do. I was about 150m from the nearest exit, 150m past the nearest entrance, so no help telephones within sight, and of course, Murphy's Law, I'd forgotten my mobile at home in the rush. It must be the first time I've ever left home in the Beta without it...

But what do you do when the car is resolutely not going anywhere? You sit there. Luckily, after a couple of minutes I tried to restart, it fired (!?) and I got out of there quick smart.

Now, the hard part (well, perhaps not so much). Once I was off the freeway the car kept running, though there were a few severe hiccups on the way. The car was quite low on petrol - I'd been planning to fill up on the way home - and it briefly crossed my mind that maybe I'd run it too far, but I don't think so, because it still fired. The problem, as I discovered on a stretch of quiet road afterwards, was sustained full-throttle running, or close to 100% throttle in any case. Hence the problem on the freeway and hence the hiccuping when I tried to accelerate away.

I'm thinking it's one of two possibles. Possibility one, probably less likely, is that the low level of petrol in the tank meant that the pump drew some gunk at the bottom, clogging the carby. Though I did put in 5 litres or so and the car was pretty ok after that, only hiccuping once on the test run which could have been the final vestiges of some gunk. Possibility two is some problem with the float. There's been a suspicious pool of residue petrol forming on the inlet manifold lately so I'm suspecting it's the latter.

One final point to ponder though. Just before it started hiccuping for the first time, the oil temperature gauge was rather higher than I've come to expect. That was my first thought when it died on me, something to do with this mildly raised oil temp. It wasn't in the danger zone, to be sure, but noticeably higher all the same. Strange thing though was that water temp was perfectly normal and it hasn't hit above 15C in Sydney all day. But the problem didn't reappear for the rest of the drive, it ran at normal oil temp, and oil and coolant levels were all fine when I checked them now. Just one of those things, I suppose, but I don't like not knowing why.

cthargiss
22nd October 2004, 10:09 PM
Sounds similar to a couple of experiences I have had. I discovered that the fuel pump is not quite strong enough if the fuel level is very low and the fuel filters are partially clogged. (don't forget the little one in the carb inlet) A full tank and new filters should cure the hiccups. Allowing the car to sit a bit let some of the gunk settle out of the filter and let the pump to barely supply the carb. The starvation primarily at WOT was the givaway.
Craig

Shant Fabricatorian
23rd October 2004, 03:56 AM
10 litres of Optimax did the trick, it's cured. The fuel filters were done relatively recently, probably about 4 months ago and it hasn't been driven all that much since then, a couple of thousand kays maybe.

SubGothius
10th November 2004, 12:00 AM
I'm not sure how relevant this may (not) be to your situation, but when I first got my '79 Zagato spider this past February, I had a few puzzling instances where the car died or wouldn't start, but then started up fine later "for no apparent reason". Sometimes it would sputter or die at night in the rain and refuse to retstart until after an indefinite wait. At one point, I'd wondered if it was nearly out of gas (car was still new to me, so I wasn't completely familiar with its fuel gauge yet), so had a neighbor drive me to the station for a gallon to get the car started up to drive posthaste to the station for a proper fillup; the car started up after feeding it the gallon, only to die again a few yards away. Splashing some leftover gas into the carb allowed it to fire up right away then die again, so spark seemed good, and fuel delivery was apparently the issue.

At some point when this happened again, I was sitting to wait between attempts to start the car, and it occurred to me that I should conserve battery power, so I started switching off accessories. I happened to have the key on when I switched the heater blower fan off, and that's when I heard the electric fuel pump change pitch and settle into a mellower purr (it's mounted in the trunk as an aftermarket replacement to the problematic mechanical OEM pump -- whenever I start the car, I have to "prime" the fuel rail by leaving the key on briefly until I hear the fuel pump sound mellow out, then I can fire it up). Hearing that change in pitch, I turned the key and she started right up.

All those times previously, I'd unwittingly, inadvertently solved the problem by shutting down the blower fan at some point without realizing that was the solution. The blower fan was apparently sapping juuust enough battery current that the electric fuel pump couldn't quite muster building a column of fuel all the way up to the carb (esp. if the car was parked pointing up an incline); shutting off the blower fan freed up enough battery current to run the fuel pump until the engine started and the (fairly new Bosch) alternator could supply power to everything just fine. This also explained my occasional problems with hesitant running or outright stalling in wet weather at night -- with the wipers and headlights and radio and defroster blower all running at once in wet, electrically-suboptimal conditions, the fuel pump was also struggling.

So now I remember to start up with all accessories turned off (especially if I'm having starting problems), and it always starts up fine. I really should get around to renewing all my electrical grounds, which will provide a more sound, longer-term solution, but at least I finally deduced WTF was going on and how to avoid it. :D

BTW, aside from this, I sometimes still get hesitant running or refusal to start for other, less-puzzling reasons, both of which are usually solved by flooring the gas pedal briefly. Full-throttle fuel pressure will usually flush out any blockages in fuel delivery, or any quasi-vaporlock conditions when the car refuses to start after being run well then shut off hot and left to sit briefly on a hot day before restarting.

Shant Fabricatorian
10th November 2004, 05:13 AM
You know, that's a definite possible. I had lights, wipers, demister all going, and the voltmeter's readings when such is the case is not exactly encouraging. It has been known to dip into the last quarter on such occasions. Switching off the demister and lights would have given it enough current to get some petrol flowing again.

The other possibility was just water and electrics not mixing terribly well. It doesn't get used in the rain an awful lot (it leaks at the top of the windscreen) and this was a proper heavy downpour. As a friend said, "I'm finding it hard not to equate water with failure." Still it has been used in lighter rain since and not given a hint of trouble so I think your explanation about the electrical system not being up to it could have the ring of truth.

Usually when I get hesitant running it's because it's not warmed up properly. Usually I try to keep it below 2500rpm until the oil temp has hit the quarter mark on the gauge. If it's still hesitant after that a quick blast normally sorts out any stickiness.

Hamish
10th November 2004, 11:41 AM
Had a similar problem with my old VX - cured by the lights getting independant relays and all the electrics being overhauled and re-earthed.
If I'd kept it - or if she who must be obeyed had allowed me to keep it - the plan was to overhaul everything possible with an 'independant' relay as all Beta owners will know that switching on electrical 'stuff' on the car at night makes the volmeter to amusing things...... .
Complicated to do all of the electrics :?: Most certainly, but worth it for reliabilities sake :wink: And don't be afraid to take out the fuse/relay box, clean it thoroughly with a suitable cleaner (I used petrol :!: but it was thoroughly cleared away before putting the fuse/relay box back in the car :!: :!: ). The difference to electrical 'performance' after this exercise is light and day.....

Shant Fabricatorian
11th November 2004, 04:46 PM
Thanks for the tips everyone.


Complicated to do all of the electrics :?: Most certainly, but worth it for reliabilities sake :wink: And don't be afraid to take out the fuse/relay box, clean it thoroughly with a suitable cleaner (I used petrol :!: but it was thoroughly cleared away before putting the fuse/relay box back in the car :!: :!: ). The difference to electrical 'performance' after this exercise is light and day.....

I was looking for something to fiddle with over the Christmas break. Looks like I found it. :wink: