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jetronic M1 vs motronic M1

3K views 6 replies 4 participants last post by  Duk  
#1 ·
could any one give me a short explanation of the difference between the jetronic M1 as on the 3.0 verde of 88' and the next step up motronic 3.0 verde of 89'? thanks in advance for any info.
 
#2 ·
Off the top of my head the Motronic would have probably had:

- Digital fuel map in the ECU (vs. analog L-Jet)
- Digital timing advance map in the ECU (vs. the L-Jet ignition module)
- Active idle control (replaced AAV)
- Cold start enrichment via ECU (replaced CSI)
- Self-diagnostic capability (check engine light probably wasn't implemented on the Euro cars, but likely there was an OBD1 diagnostic port)
 
#4 ·
No, the US S4 cars flash out codes using the check engine light. There's a button behind the passenger seat that activates this. I don't think the Euro cars had this, though, and may have just had a diagnostic port. But I could be wrong.
 
#7 ·
I wouldn't go putting the Alfa spec version of the Motronic on any sort of pedistal. They must have used the cheapest, most whittled down version of the Motronic known to Germans. :001_tt2:

They still squirted all of the injectors together.
They still used ye-olde throttle position switch.
They maintained the use of the vane/flap type air flow meter.
And they still had a single coil, distributor based ignition system.

In my opinion, if you aspire to get some decent results from an Alfa engine, especially the V6 engines, then you need to go with either a suitably tuned later/better version of the Motronic or simply a decent after market programmable computer that is based on crank angle sensor engine positioning to atleast squirt the injectors in pairs.