Currently suffering a glorious 15mpg or so from the 1.4 engine. Popping when slowing to junctions at high revs or when the revs drop after you blip the throttle. What's borked (just bunged in a new air filter, still pops).
And I've just pulled a spark plug, they all look pretty alright, though less crudded up than the "normal" one in Haynes.
stuck choke, massive air leak, very bad ignition timing, hand brake on, shagged engine, terrible driver, banger racing in second.
mrcheerful
Terrible driver shouldn't get a 1.4 down to 15mpg. FWIW, I managed 30 out of a Ka.
Knackered carb? I had an E-reg 340 1.4 for a while and it did exactly what you describe. Turned out that the heavy airfilter is just bolted to the carb, and over the years it had damaged the seal between the top and bottom of the carb. Trip to the scrappy and £25 sorted it.
hth mike
Could be a cracked carb housing, or a warped base gasket, both are fairly common. IIRC these use a Pierburg carb which were pretty crap. Also check all the breather and vacuum hoses too, any of those leaking won't help much.
I still want to know what the f*ck PeteM was doing to get a 406 HDI down to
17mpg! My last tankful in the A6 was definitely one of the worst at 35.7mpg, but that had been driven very hard over that tank. Still shouldn't be that low though. It's just had an oil and filter change, air filter not too long ago, fuel filter a few hundred after the recent oil and filter change, so the only potential things left are to get the injectors reconditioned, or the MAF sensor cleaned. Don't know if there's anything wrong with the MAF sensor, as it performs absolutely fine, but economy should definitely be a good 5mpg or so better all round than what I'm getting at the moment.I'm guessing there isn't a DIY method to properly cleaning/reconditioning injectors - just a case of getting them professionally re-done or an exchange set. Any ideas as to whether getting some from GSF/Eurocarparts is going to be significantly worse than OEM ones?
Peter
-- "The truth is working in television is not very glamorous at all. I just go home on my own at night and sit alone and eat crisps."
No, solex carb. Only the last B14.4E used a decent twin choke weber!
Tim..
Popping on the overrun is often a symptom of an exhaust manifold crack or leak.
It's a Renault engine (hence the Solex carb). Might be worth getting a carb recon kit from Webcon (who supply Solex bits these days), as the internals are known to wear eventually.
Alternatively a good strip down and clean up might release a sticky throttle mechanism or blocked jet.
You should be able to slap on the twin Weber 32DRT from a later Volvo, or 1.4L Renault 5 automatic though I'd have thought. Plenty of Renaults using that engine and carbs knocking around in breakers yards...
Rich.
Knackered carb? I had an E-reg 340 1.4 for a while and it did exactly what you describe. Turned out that the heavy airfilter is just bolted to the carb, and over the years it had damaged the seal between the top and bottom of the carb. Trip to the scrappy and £25 sorted it.
hth mike
This is a common problem on the 1.4 340 - the top of the carb works loose and needs nipping up from time to time. Take the air filter off and tighten the screws (careful now....) Check the nuts holding the carb onto the manifold.
Ah, yes it was the 740 that had the Pierburg. It was the Solex to which I was referring anyway.
The big Pierburgs on the B200 / B230's are a much better carb, one cos they're mounted miles from the engine so dont get heat soak problems, and two, so bloody big their thermal mass is huge so the bases dont warp.
The Solex on the B172 engines are sods for doing this!
Tim..
I had to replace the one on our 740, midn you it had done 155k miles.
Oh yes.
-snip-
Indeed they do - on the original Renault version (F2N) you're lucky to get beyond 50,000 miles on the 1.7 litre Renault 5s before the carb base warps. Luckily the Weber replacement I fitted on mine seemed to be more solidly built round the bottom half of the carb - maybe an attempt to keep it flat for longer?
Rich.
It's not going to be easy. Just drive around York all day, park up for lunch and leave it idling, so on and so forth.
Okay so it was during Kermit's running in period, but he only returned 25.7 mpg over one tank in the winter. :-(
It's not difficult to get 30 mpg from Kermit in the city, either.
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