Cranking Advance Drops off between attempts to start

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woznaldo
Helpful MS/Extra'er
Posts: 120
Joined: Sat Dec 11, 2004 7:51 am
Location: Canberra (Previously UK)

Cranking Advance Drops off between attempts to start

Post by woznaldo »

I was having Cranking PW problems, but I they a sorted now (see thread: http://www.msextra.com/forums/viewtopic.php?f=4&t=65888) so I thought it prudent to start another thread particular to the current issue.

1397cc OHV Renault C1J with Garrett T2 turbo
440cc/min injectors
EDIS4 Wasted Spark

I have been playing about with Cranking Advance Angle and I almost had the car started with around 4 deg BTDC.I slowly increased the Cranking PW (0.2 per adjustment) and was getting a little (if at all) better each time, until the display started showing 0 deg BTDC??

I seem to be getting a strange RPM peak when I initially crank the engine which then drops to either the cranking RPM or to between 450-600 if the engine is trying to fire up. When the Cranking Advance drops off, the engine doesn't seem to want to fire at all.

I currently have my cranking RPM set at 500 (generally the engine cranks at 250 RPM), do I need to set this higher?
Trying to make my Renault 5 GT Turbo a bit more driveable and a lot more reliable!

1988 Renault 5 GT Turbo MS2 Extra
1972 Datsun 510 - L18 on Twin Webers
1973 Jaguar XJ6 - 4.2 XK on std twin SUs, but plans to squirt in the near future...
slow_hemi6
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Posts: 4122
Joined: Fri May 07, 2004 3:33 am
Location: Australia

Re: Cranking Advance Drops off between attempts to start

Post by slow_hemi6 »

From memory EDIS module controls the cranking advance not the MS. SAW only takes effect over 400 or 500rpm.
Find the Manuals up top under Quick links: Manuals. :RTFM:
Cheers Luke
woznaldo
Helpful MS/Extra'er
Posts: 120
Joined: Sat Dec 11, 2004 7:51 am
Location: Canberra (Previously UK)

Re: Cranking Advance Drops off between attempts to start

Post by woznaldo »

When I set the cranking advance at -10, TunerStudio displays -10 during cranking. When I change cranking advance to +5, TunerStudio shows +5 or 0??

When TunerStudio shows +5, the engine tends to cough and splutter like it's trying to start, but when it shows 0, it turns overs without firing? Apart from the occasional cough back through the throttle body on initial crank?

Can anyone confirm how EDIS works during cranking?
Trying to make my Renault 5 GT Turbo a bit more driveable and a lot more reliable!

1988 Renault 5 GT Turbo MS2 Extra
1972 Datsun 510 - L18 on Twin Webers
1973 Jaguar XJ6 - 4.2 XK on std twin SUs, but plans to squirt in the near future...
slow_hemi6
Super MS/Extra'er
Posts: 4122
Joined: Fri May 07, 2004 3:33 am
Location: Australia

Re: Cranking Advance Drops off between attempts to start

Post by slow_hemi6 »

I have never heard of EDIS being able to have ATDC timing. It's range is 10 BTDC to 59 BTDC. There is no SAW value for anything under 10 BTDC. So there is no point putting impossible cranking advance into the parameter. Almost 100% certain cranking advance only works on MSnS(basic triggers) or toothed wheel anyway. Do you have a timing light?
Find the Manuals up top under Quick links: Manuals. :RTFM:
Cheers Luke
woznaldo
Helpful MS/Extra'er
Posts: 120
Joined: Sat Dec 11, 2004 7:51 am
Location: Canberra (Previously UK)

Re: Cranking Advance Drops off between attempts to start

Post by woznaldo »

Thanks for the reply slow_hemi6,

I double checked the VR sensor clearance and it's 1.5mm. I think that should be fine as the car has run with this setup on ignition only and the old carby just fine.

I did find this reference: http://www.megamanual.com/ms2/EDIS.htm That says: "EDIS Range: 64 - 1792 µsec (57½° BTDC to 10° ATDC)"

I do have a timing light and tried it earlier today, only to find it no longer works? I'll grab another from a mate tomorrow and try again!

I will double check all the mechanical items this week to confirm there isn't a massive air leak somewhere.
Trying to make my Renault 5 GT Turbo a bit more driveable and a lot more reliable!

1988 Renault 5 GT Turbo MS2 Extra
1972 Datsun 510 - L18 on Twin Webers
1973 Jaguar XJ6 - 4.2 XK on std twin SUs, but plans to squirt in the near future...
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