There's a couple versions of these out there, but to my eyes, they were difficult to read, or lacked info, so I made these.



Single page, landscape:

(EZF_LH22_32V.pdf)

(EZF_LH22_16V.pdf)


Green = sensor
Brown = ground
Black/Red = +12v
Purple = RPM signal


Notes:

-LH pin 15-
16V, 32V, inhibit decel inj. cutoff, is only implemented on green motherboards.
'86.5 LHs with yellow motherboards do not have this feature (missing components).
SAAB/Volvo with LH2.2 use this input to code for automatics.

-LH pin 19-
32V, LH octane loop, changes the O2 sensor loop rich/lean pattern slightly.
16V, Check Engine Light, indicates if the MAF signal is out of spec., LH in 'limp home' mode.









LH 2.2 LH22 LH2.2 ECU connector connectors terminal terminals pins pin plug S3 S2 85 86 86.5 ignition fuel injection

 

These are great.
Thank you!

 

Great reference material.

*subscribes*

 

Thanks! Added to the library.

 

Thanks Ken. I think some of this applies to my Euro as well.

 

Printing now, thank a bunch.

 

Fantastic much needed. Thank you!

 

Jim - I split the LH into two versions for y'all ROW types. EZFs are the same, just with different maps.





For those who log stuff*, note the MAP sensor (= vacuum level) voltage on EZF pin 21. Contrast this with the MAF sensor (= air flow) voltage on the LH pin 24.

* I'll be using an Innovate SSI-4.

 

Updated with one page PDFs.

 

Updated with revised and new info.


I was wrong, pin 24 on the LH is not the MAF voltage, but a load signal for EZ-K ignition. (SAABs, Volvos use LH2² with a single distributor version of EZ-K.) 0~200 hz pulses. I see 0 when decelerating, 11 at idle, 25 cruising, 109 max @ 6400 rpm jumping to 168 when the rev limiter kicks in.

Grounding pin 23 opens the idle control valve, pin 10 closes it. These switch back and forth rapidly to keep the idle speed. Oddly, the idle control keeps cycling all the way up to ~2500rpm, where it levels off with a 55/45% bias closed.




Here's how to solder in a wire for a road speed (speedometer pulses) input for logging or satnav on the cruise control plug, pin 11:

 

Updated 32V JPG, and PDF.


LH 32V pin 15 is an unused coding input for automatics. It is implemented in the EPROM code, but for some reason was not wired into the harness connector.

Normally, when you lift off the throttle when over 2000 rpm, rpms will drop to 1200 rpm or so for a brief period before dropping to around 700*. Ground pin 15, and it drops to idle 'gracefully'.



*This affect is quite noticeable with my S300s chips, and creates a throttle blip to aid shifting.

 

Thanks Ken!

I can attest to this. It was a little unexpected when I got the new chip a few weeks ago and started driving. At first I thought it was because I was wearing work boots and wasn't shifting right. Then I tested it and saw that there's a noticeable 'blip' when you lift to shift. It will take a little getting used to, but when accelerating quickly though the gears it definitely helps.

Someone on here once wrote about the shifting of the 928 that you can't just slam it into gear, you kind of 'offer it up' and let it drop into gear. This is smoother with the new chip and quicker.

 

Very nicely done. You need to add the info that in '90 and up, the cable is on the other end of the connector...

 

Er...Wally, EZK and LH2.3 will be in a different thread.

 

Thanks, Ken - That will help teach me to read more carefully!