m103 first start unsuccessful

VladimirYesin

m103 engine. Doesn't start at all.
What I checked:
1.wiring connection - all good

Fuel pressure 4.5 bar
Cleaned all sparkplugs
4.ICV controlled by stock ECU

Cranked the engine multiple times, sometimes it feels like it wants to start, but still doesn't.

Here are logs from old and new commanders.

Please point me into some direction .

20260828-184516-first-start.zip

13kB

log-jetronic-6a09-v417-20260828-184057.csv

36kB

oleksiyko

Air leaks?

VladimirYesin

oleksiyko
i thought air leaks could lead to poor idling, but in my case it just doesn't start

JHM

Everything looks good in the log, except the battery is dead.
Maybe wet spark plugs?

VladimirYesin

The problem was crankshaft position sensor.
So the car started and I did a first small test drive.
Questions:

When ignition on (engine not running) "Idle" stays green if acceleration pedal is not pressed. But when I start engine - it's not green any more. Is it expected behavior?
Idle is controlled by invent. I have automatic transmission. When I correct idle at 750 while being in Park, after selecting "Drive" RPM drops and car nearly stalls. I only changed idle minimal position 0 and 60 deg.
After the car cooled down - the start is almost impossible, so I increased idle min position at 0, car started but RPMs are fluctuating (see log 2)

Please let me know how to fix my issues.

first-drivejetronic-6a09-20260904-202743-v417.bin

8kB

cold-start-log-jetronic-6a09-v417-20260904-203258.csv

110kB

first-drive-log-jetronic-6a09-v417-20260904-164045.csv

473kB

oleksiyko

IMHO: "Ext" or "Ac"wire must to be connected to selector of transmision, then Invent will know when to inrease ICV position.

VladimirYesin

ok, my main question now is the "idle" indicator. When the engine is not running, "IDLE" is green in commander. I also measured resistance between pins 1 and 2 ( idle and ground ) and it is 0 Ohm. Once i start the engine, "IDLE" indicator is NO LONGER green and resistance becomes like 200 Ohms...
Do you think my throttle switch is bad?

VladimirYesin

ok, the problem with IDLE not engaging when engine starts was solved with a new throttle.
The issue is now that when I start the car I have to crank longer than I wanted and the idle RPMs at start are very low, but then they raise and stabilize.

log-jetronic-6a09-v417-20260905-111659.csv

105kB

oleksiyko

What ICV position do you have when iddling OK?

VladimirYesin

where can i look that up?

oleksiyko

VladimirYesin

stable r

oleksiyko
stable rpms are at ICV 40-41%

oleksiyko

To the cell 1 enter 40, to the cell 2 - 36, and try to start engine.