SaabCentral Forums banner

1 - 18 of 18 Posts

·
Registered
Joined
·
4,666 Posts
Discussion Starter #1
I have been having trouble with the AMM on the T16S. The previous unit broke a wire and its (2nd hand) replacement doesn't seem to want to adjust up from 0.15%CO :evil: Unfortunately the car runs the rare plastic bodies 017 unit which was only used for around a year between the metal bodied 005 and the switch to Lucas.

I know I can't just swap in a 005 unit (I believe its wired differently) which is a shame as I have accesss to a pile of these, but and heres the biggie, can I swap the AMM and change the ECU for a matching unit at the same time without touching the wiring on the car, or will pins have to be swapped in the ECU plug?

Should I go to bed this evening with the Haynes and have a good read?
 

·
Registered
Joined
·
4,666 Posts
Discussion Starter #2
Spent the afternoon playing with AMMs and ECUs :cheesy: :cheesy:

Started by reading the Haynes and frankly useless is too polite. The wireing diagrams are helpfully labelled 'Typical Early Car' and 'Typical Late Car'. Well mine is an atypical intermediate car and nothing in the Haynes matched up. The diagram featured an AMM with 5 wires which is really helpful as my car has six (I assume that this is Lucas connection).

Fortunately Matthew has a set of Genuine Saab Manuals including a wiring diagram for '89- cars (hopefully mine) and the Injection guide for -'88 which covers the 005 AMM.

Reading the manuals showed that both AMMs have 4 wires to the ECU, one to earth and one to the igniton amp. Even better the colour and wiring codes are the same and the wires connect to the same pins on the ECUs. As I expected the plugs were found to be in a different order on the AMM though :evil:

A plan was now forming. If the connectors on my car could be ordered to match those of the earlier unit then everything else would fall into place.

A small precision screwdriver was procured and the work started. Unfortunately the connectors refused to leave the warmth and security of their housing no matter how much we swore at them.

This lead to plan B. Cut the plug out of my loom, do the same for the donor car and then solder the two parts together. This left myself and Matthew trying to solder 6 small wires together, balanced over the top of the engine bay in strong winds, low temperatures and the odd shower or two. Eventually it was done and the wires connected :D .

The AMM was attached to the inlet system, the plug connected and the car cranked over. The car tried to start (which was a huge improvement over the previous time I tried an 005 in it) but was running so rich it could barely idle and I could see my precious Optimax disappearing out ot the exhaust system.

Mmmm, did this mean that the idle maps are vastly different as well. The ECU from the donor car was removed and then fitted in place of mine. This time the car started and idled perfectly. Infact, it now idles better than I can ever remember over the last 11yrs of known ownership.
 

·
Registered
Joined
·
4,666 Posts
Discussion Starter #3
Wire Colours

For those interested the AMMs use the following wire colours/locations.

005 AMM (metal bodied)

Pin Colour Destination
1 Red/White ECU Terminal 8
2 Brown/White Ignition Amp
3 Blue/White ECU Terminal 6
4 Black Earth
5 Orange ECU Terminal 7
6 White ECU Terminal 14

017 AMM (plastic bodied)

1 Black
2 Blue/White
3 Orange
4 Red/White
5 Brown/White
6 White
 

·
Banned
Joined
·
7,270 Posts
so you've swapped your plastic-bodied AMM to a slightly earlier metal type and changed the ECU for a compatible one. The connector for the AMM had to be changed because the pins wern't the same way around. Now the car is better than it was and ultimatly this conversion can be eaisly achieved if you know which bits go where.

right ?


Sounds good.
 

·
Saab Mad
Joined
·
14,069 Posts
Right.

The work was quite straightforward once we had all the technical information to hand. Only problem was being unable to unclip the connector's crimps in order to swap them, hence having to solder on a new connector from a different car.

I'd still like to know exactly why the 005 (metal) AMM wouldn't work with the car's original MY89 ECU.

__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote
 

·
Registered
Joined
·
4,666 Posts
Discussion Starter #7
More importantly there are more 005 bodied AMMs available 2nd hand so if I break any more it is far easier job to source a spare.
 

·
Registered
Joined
·
81 Posts
so, could a 1990 and up ECU + AMM be fitted in a 1985 SPG.........:eek::eek:

Or are my hopes for easy fuel remapping shattered until I megasquirt.....

CN
 

·
Registered
Joined
·
221 Posts
if saab dont have it look into volvo ;) (240/740/440/460/480) they got that same plastic amm + even the number.

ecu fit but amm.. go from plastic to metal u need to change the amm plug so the plus (+) wire dont fit ground (-) if plastic amm plug is fit to a metal amm then plus hit the minus and if metal amm plugs is fit to a plastic amm then plus fit minus (same deal.. result: your ecu is fry chicken tonight)

p.s. if u are thinking about megasquirt tjhen do it , no need of other ecu instead of stock one.. just buy the megasquirt and get somewhere orginal map setup , i should have done that then i kill my ecu :) but lack of $ was fault.
 

·
Saab Mad
Joined
·
14,069 Posts
comfortablynumb said:
Matthew said:
What would be really useful is the cranking enrichment, acceleration enrichment, cold-start enrichment and part-throttle cruising parameters that are more difficult to map. Any ideas? :)
I know this guy, http://www.jakstollperformance.com/index.html, does ECU remapping (LH2.2 and LH2.4).

Maybe he could help with the values?
If he can remap the LH ECUs then yes he should be able to read off all those parameters. What would be best is a complete dump of the LH ECU's maps for everything to help out those going with aftermarket systems.

Do you think he'd agree to that? :)

__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote
 

·
Registered
Joined
·
81 Posts
Matthew said:
If he can remap the LH ECUs then yes he should be able to read off all those parameters. What would be best is a complete dump of the LH ECU's maps for everything to help out those going with aftermarket systems.

Do you think he'd agree to that? :)
He's a regular at Saabnet...:roll:,would it be proper to invite him to post here as he's not a sponsor here??

CN
 

·
Registered
Joined
·
4,666 Posts
Discussion Starter #15
Matthew said:
What would be really useful is the cranking enrichment, acceleration enrichment, cold-start enrichment and part-throttle cruising parameters that are more difficult to map. Any ideas? :)
Accel enrichment may not be so useful when comparing between Bosch LH and Megasquirt as one is MAF based and the other MAP.
 

·
Registered
Joined
·
4,666 Posts
Discussion Starter #16
comfortablynumb said:
so, could a 1990 and up ECU + AMM be fitted in a 1985 SPG.........:eek::eek:

Or are my hopes for easy fuel remapping shattered until I megasquirt.....

CN
Anything is possible. As Matthew mentioned though, the work was only possible as we had access to the wiring diagrams.

Looking at Jak Stolls webpage it would appear that he can remap both LH2.2 and LH2.4 so I wouldn't have thought that you would need to remap.
 

·
Registered
Joined
·
81 Posts
Alex said:
Anything is possible. As Matthew mentioned though, the work was only possible as we had access to the wiring diagrams.

Looking at Jak Stolls webpage it would appear that he can remap both LH2.2 and LH2.4 so I wouldn't have thought that you would need to remap.
I'ts a money thing, A chip for the 1990+ is cheap in comparison to Stoll's remap.

MS of course is cheap and "infinately" adjustable, not to mention it just sounds like a lot of fun tinkering........:cheesy:

CN
 
1 - 18 of 18 Posts
Top