AAn Ecu been socketed?!

[UrS4boy]

It was when the ECU's were swapped from 551A to 551AA. 551A is socketed, 551AA and 551B (the autobox one, not RS2) isn't. That might not be 100% true of course, just my experience from pulling apart 30+ ECU's.

That seems reasonable. Unfortunately, my good friend Kate no longer knows about the 551A version. In fact, as of 01/01/2002 she doesn't really even know about the 551AA version since it has been superceded to a rebuilt 4A0997551X.

Perhaps earlier documentation (prior to the 01/01/2002 date) would provide a VIN number break between 551A and 551AA.

Matters only to the obsessive parts trivia freaks.

(me)

[prj]

As far as I know, it was only the very early 92 model year UrS4s, e.g. ones built in the Aug 91 to Oct 91 period that have socketed ECUs. At some point, Nov 91 (?), they started soldering the chips without the sockets. There is no documentation on the breakpoint on this, unlike the switch in the location of the cam position sensor in mid-Feb. 92.

It was when the ECU's were swapped from 551A to 551AA. 551A is socketed, 551AA and 551B (the autobox one, not RS2) isn't.
That might not be 100% true of course, just my experience from pulling apart 30+ ECU's.

[UrS4boy]

Yes, some ECU's are indeed socketed from the factory.
Mostly the earlier ones from my experience. For the later ones it's a soldering job.

As far as I know, it was only the very early 92 model year UrS4s, e.g. ones built in the Aug 91 to Oct 91 period that have socketed ECUs. At some point, Nov 91 (?), they started soldering the chips without the sockets. There is no documentation on the breakpoint on this switch, unlike the location of the cam position sensor which changed location in mid-Feb. 92.

[prj]

im just relatively new to motronic ecu, id normally use autronic or DTA for better results on live mapping.

Just pointing out that keeping motronic without knowing how to map it and screwing with boost without at the bare minimum adjusting the last cells in the fuel/ign chip while some wannabe tuner turned off the load limiter in "tuned software that makes your car go fast" is the fastest way to disaster...
Sorry, just my experience... I deal with such cases weekly

Would a 91 3b ECU be socketed from factory?

Yes, all 3B are socketed.

[Sleeper_Avant]

ive been building very high power cars for myself and customers for many years, im not about to do any of the above for a few extra horsepower.

im just relatively new to motronic ecu, id normally use autronic or DTA for better results on live mapping.

i was only curious about the socketing thats all

thankyou for the info.

[ian4455]

Would a 91 3b ECU be socketed from factory?

[prj]

Boost isnt a problem as its controlled outside the ECU via stand alone

And why?
On stock turbo that is mostly ok, as long as you don't go over 1.5 bar.
Then again, with stock software you will have fuel cut long before.

Manual boost control, RS2 hardware and software without load limiter is how very many people have bent their rods or blown up their engines.
If you run on your car what you have written in your signature, you will need either a standalone or very in-depth remapping and a different maf.

[Sleeper_Avant]

Boost isnt a problem as its controlled outside the ECU via stand alone,
Will be measuring various things tomorow when i take it to work

cheers for this,

Sean.

[prj]

Yes, some ECU's are indeed socketed from the factory.
Mostly the earlier ones from my experience.
For the later ones it's a soldering job.

Check that your ECU is not labelled 551A. If it is, you can't just stick any AAN chips in there, you'll need a custom boost chip.
Measure R201... on RS2 it is 5.6k on AAN 6.5k iirc.

[s2_wot]

Some ecu's were socketed from the factory AFAIK.

[Sleeper_Avant]

took my standard ECU out for general poking around purposes and noticed that its already been socketed and the chips just plug in and out, is this normal for a 92 AAN?

very interested to see as cant find any info on this, need to take it to work tomorow and measure resistance to see if its been RS2`d,

intrigued, Sean