| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 1168.1 | Heard that before!! | IOSG::REES | | Thu Jul 26 1990 16:40 | 4 |
| Don't know anything about it, but my dads Granada does the same
thing...!!
|
| 1168.2 | | ANNECY::MATTHEWS | M+M Enterprises. Thats the CATCH | Thu Jul 26 1990 16:43 | 5 |
| Don't all cars do that ??? All mine do. As to the reason, it is
probably related to the engine sucking in petrol/air due to the
engine turing over, rather than you pumping in the petrol/air
when you have the accelerator open ... this could be complete BS
by the way.
|
| 1168.3 | Trabi's don't! | HOO78C::DUINHOVEN | Dutch treat | Thu Jul 26 1990 17:03 | 9 |
| Al cars I've driven do the same.
The only ones, which don't are two-stroke ones like Trabi's.
They don't have much "brake" performance downhill anyway.
That will improve, if ignition is switched off downhill.
You'll have some fun, when switched on again at the end.....
Hans
|
| 1168.4 | I don't think that its BS!! | NSDC::SIMPSON | File Under 'Common Knowledge' | Thu Jul 26 1990 17:16 | 3 |
| You could all be right - I've only noticed it because I've got the window
open in this hot weather. Here in Switzerland there a lot of hills to pop
up and down, so I guess that I notice it rather more than I would in England.
|
| 1168.5 | Carburettors only | IOSG::MARSHALL | Harry Palmer | Thu Jul 26 1990 17:34 | 12 |
| Petrol isn't pumped into the engine (unless you have injection, but assuming
it's a carburettor...) the throttle controls the size of orifice through which
the petrol / air mixture is sucked, hence the quantity of mixture reaching the
engine. If you close the throttle but (due to going downhill) the engine revs
stay high, you're bound to get the wrong quantity and mixture, hence mis-firing.
If it's noticeably bad, you may find the idle speed adjustment (ie the small
amount the throttle stays open when you take your foot off the pedal) or
mixture adjustment (ie ratio of air to petrol) need adjusting. There may also
be a problem with the bypass-idle circuit, if your carb has one.
Scott
|
| 1168.6 | But... | ANNECY::MATTHEWS | M+M Enterprises. Thats the CATCH | Thu Jul 26 1990 17:49 | 7 |
| re: .5
Could the suction created with the revs high and zero throttle opening
cause the throttle to open, and gulp in some petrol/air ??? Suppose it
depends on how strong the throttle return spring is ...
Mark
|
| 1168.7 | The cars in question.... | NSDC::SIMPSON | File Under 'Common Knowledge' | Thu Jul 26 1990 18:10 | 7 |
| Thanks for the info. so far.
.5 shows me that I ought to say what sort of fuel feed I have - 'cos one the
cars does have injection.
I've got a VW Transporter - transitorised ignition; still has a distributor
VW Golf GTI.
|
| 1168.8 | race tuned exhaust? | SHAPES::BUCKLEYC | Bareback on the Shark | Thu Jul 26 1990 18:11 | 4 |
| Having a small hole in the exhaust, near the engine can cause popping
Chris
|
| 1168.9 | | GVA01::STIFF | Paul Stiff, EHQIM-OIS DTN:821 4167 | Fri Jul 27 1990 17:26 | 4 |
| My modified 1275GT Mini does that, but I retarded the ignition a
few degrees, and that and the pinking stopped.
Paul
|
| 1168.11 | 'Cool, man'! | CSSE::WAITE | | Fri Jul 27 1990 20:16 | 7 |
| Back in my high school days, a properly sounding 'poping off' sound
was thought to be a sign of a well tuned/timed engine and was 'cool'!
Nothing quite like a slightly warmed over Ford V8 flathead to produce
the desired effect.
Dick_who_is_showing_his_age
|