Syncro 4&4 Discussion and Q&A last answered over 2 years ago.
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I know tencent was doing that Mod, I am lucky enough not to have had to remove the oil pump. Syncrospares found my oil leak though whilst doing the insurance repairs, the oil was leaking out through the middle of the high pressure switch behind the crank pulley wheel.
Well done on the MOT. Mines up in January, but the garage that has done it for 5 years has closed so got to find someone else who knows about VW rear wheel hub bearings Even new ones.
The engine sounds sweet because this is what it looked like 5 years ago.
that's not the wbx engine stand it's the VW delivery crate - I had 4 of those through my hands before stock ran out on a buy one, get one half price only one return required basis, worked out at £1200 inc the vat each, 2 went to Hacksaw Bob (one is in Max's van) and one is in Beaker and one in Tonka, neither of which I have any more, I'm making do with a factory original 153k miles engine
Ian I have a VW 307 engine stand (2 actually one's with SimonTMT) and another VW 309 which Stan currently has, could come your way as you are more likely to find time and space to use them that I am at the mo
Aidan wrote:I had 4 of those through my hands before stock ran out on a buy one, get one half price only one return required basis, worked out at £1200 inc the vat each
Aidan, you tease! If I could turn back time...
Last edited by syncropatrick on 23 Nov 2011, 21:03, edited 1 time in total.
Syncro for sale Syncro 16” AGG Dehler Profi hightop Caravelle/Camper
Aidan wrote:
Ian I have a VW 307 engine stand (2 actually one's with SimonTMT) and another VW 309 which Stan currently has, could come your way as you are more likely to find time and space to use them that I am at the mo
Ta very much indeed! Looks like the works' Vito will be well loaded up after the next visit to TalbotGetriebewerke
1985 Oettinger 3.2 Caravelle RHD syncro twin slider. SA Microbus bumpers, duplex winch system, ARC 7X15 period alloys
have you ever hooked up an exhaust gas analyser at the same time, wondered how the reading would correlate to the Lamda and whether this would reflect changes in the richness.......
One of my other "projects" is an E38 Bimmer with the 4.4 V8, got full laptop diagnostics running so you can see lambda on both banks and what the adaptives are doing etc - great way to confuse the hell outta yourself
have you ever hooked up an exhaust gas analyser at the same time, wondered how the reading would correlate to the Lamda and whether this would reflect changes in the richness.......
One of my other "projects" is an E38 Bimmer with the 4.4 V8, got full laptop diagnostics running so you can see lambda on both banks and what the adaptives are doing etc - great way to confuse the hell outta yourself
MM
Took me two years to properly work out what was going on with the lambda, I am an only an enthusiastic amateur!!!
Other than it passed I have no idea what the MOT level was.
This was the readings three years ago when I had her dyno'd.
KarlT wrote:If the micro switch cuts the injectors, how does it tick-over?
My guess work would say that when you release the throttle the injectors would drop back to tick-over levels, which would be a very lean mixture at 3000rpm. I dont know whether the ecu can tell the difference between proper idle, and over-run. On the over-run the throttle position switch would be telling the ecu that the throttle is closed, but the AFM would show that more air is being sucked through the engine. I dont know if the ECU would cut all petrol injection in that over-run situation. If it did it might explain the slight 'bump' you sometimes get when you open the throttle after a period of over-run, this would be the ecu going from injector close down to injection.
It's all guess work really, I would put my money on the injectors always squirting at least a tick over amount of fuel, but that being enough of a reduction to give engine braking. Tick over must give less than 5hp, otherwise the alternator and power steering wouldnt stall the engine without intervention from the idle stabilisation unit.
IIRC the ECU for an auto is slightly different to a manual. I am guessing that one of the differences is the mapping as in a closed throttle situation on an auto you don't have the transmission still turning the engine over so the injectors have to default to tickove otherwise it would cut out completely.
I guess it depends on whether it was considered a good thing to have an ultra-lean mixture on the overrun (safe as it's off load, so the engine momentarily becomes an air pump) or to save a tiny amount of fuel by shutting down completely until the rpm signal gets close to idle values.
Going lean would be better for a smoother progression onto load, as opposed to an injector shutdown followed by a sudden return to on-load conditions (possibly compensated for with a "fire all" signal, but not very refined)
I don't know enough about Bosch systems TBH.
1985 Oettinger 3.2 Caravelle RHD syncro twin slider. SA Microbus bumpers, duplex winch system, ARC 7X15 period alloys
Thanks for the video. It allowed me to verify my fuel pressure readings. Was thinking of fitting a lambda sensor, but won't bother now.
I would like to comment on the function of the vacuum line to the fuel pressure regulator. It is common belief that it is there for enrichment of some sort, but its real purpose is to maintain a constant pressure gradient across the injectors. Where you are revving the engine you can observe the fuel pressure dropping when the revs are increasing and vice versa. Fuel pressure is simply following intake air manifold pressure through the vacuum line and the difference remains constant at around 2.5 bar at all times. If you keep the revs high you will observe the fuel pressure dropping and remaining at a lower level than when idling.
Even new ones.
