PorKen

I was reading through the Service Bulletin for '85 EZF/LH and saw something that caught my eye.

The Temp II on 32V cars has two separate sensors; one for LH, and one for EZF. According to the bulletin, the EZF side: "...advances ignition timing in partial load range with a cold engine for better pickup".

I've noticed that my '86 is a bit dull on pickup when warm (even with 3° cam advance), but noticeably perkier in this area when cold. As far as I've seen on other cars, this period of advance is retarded by various methods so as to reduce NOx emissions.

If I disconnect the EZF wire to Temp II, and wire it through a 2K ohm resistor (< 85°F) to ground, I could retain this advance?

(*Update* - works, see page 4)

danglerb

What about just increasing the overall advance?

Mike Frye

Porken,

I can't see how it would hurt anything.

Here's one: How about wiring it through a Potentiometer or a switch that you could adjust or flip from the driver's seat?

sharkmeister85

I'm sure glad Porken bought himself one of the '85-'86 MY's. I fully expect him to have me driving a 400 rwhp monster before too long, through the careful use of bubble gum, bailing wire and maybe a little duct tape (Canadian models only).
Glenn

PorKen

From the limited information in the bulletin, I think that it's a programmable threshold. Although, (I think unlikely) it could be variable.

The specs are the same as for the LH side, in ohms:
32°, 4.4 - 6.8 K
60° - 85°, 1.4 - 3.6 K
105°, 1.0 - 1.3 K
175°, 250 - 290
212°, 100 - 210

Maybe I'll use 5 or 10K to be sure.

Jadz928

I've also noticed my car is perkier when it's cold or cool outside. I'd be curious to see how this works.

What are the drawbacks?

Mike Frye

I'm thinking the only drawbacks would be the reason it's variable in the first place, as Porken says:
'this period of advance is retarded by various methods so as to reduce NOx emissions'

PorKen

Possible pinging (pinking for Canadians ).

Part of the cold effect is the air temp/density. Also, the EZF checks the air temp sensor (Temp I, in the bottom of the air filter box) and retards by 3° if the intake air temp is over 122°F.

Notes:
Unplugging or shorting the Temp I is seen as a fault = -3°
The 'octane loop' plug appears to work by grounding the Temp I input = -3°
The LH doesn't use Temp I, it relies on the MAF

Richard S

Then he could call it a PorKentiometer and sell it to us.....

Rich

John Speake

You'll be able to fully remap it to whatever you want when the LH2.2 ST is done.....

Jadz928

John,
I assume that does not apply to the early LH of my 84?

PorKen

I can't wait!

No really, I can't wait...must have more, now.

Vilhuer

There are sometimes setbacks in development. '86.5 below was supposed to be development mule for LH2.2 SharkTuner. Luckily there are other local cars for Niklas to use.





928 will live on, new owner is already fixing it.

PorKen

Moose?

Vilhuer

Light pole, moose wouldn't leave so pretty scars.