[EWealleans]

Hello, hope someone can shed some light. 900i 1992 vert. CEL problem (please continue to read!), Tech2 blamed Fuel injectors. Replaced all the fuel injectors, cleaned the TPS (well, my garage did) and for about 40 miles my Check Engine Light stayed off ; now back on again, and sounding almost as rough as before. Tech 2 not possible as back at home now where we still use an abacus to shop.

I'm assuming it's not a fuel problem, is it likely to be the AMM? It idles at 800 sometimes, but also 1000 (though it seldom hunts). It needs a new cat as the incumbent is well broken up inside as it rattles like a good 'un. Would this affect the idle? I'm thinking that it may be affecting the Eng. Man System if it's that bad. Any advice gratefully received.
Ez

 

[TooMany2cvs]

Hello, hope someone can shed some light. 900i 1992 vert. CEL problem (please continue to read!), Tech2 blamed Fuel injectors. Replaced all the fuel injectors, cleaned the TPS (well, my garage did) and for about 40 miles my Check Engine Light stayed off ; now back on again, and sounding almost as rough as before. Tech 2 not possible as back at home now where we still use an abacus to shop.

I'm assuming it's not a fuel problem, is it likely to be the AMM? It idles at 800 sometimes, but also 1000 (though it seldom hunts). It needs a new cat as the incumbent is well broken up inside as it rattles like a good 'un. Would this affect the idle? I'm thinking that it may be affecting the Eng. Man System if it's that bad. Any advice gratefully received.
Ez[/b]

That late, I presume it's Lucas injection? If so, it's dead easy to read the fault codes out.

All you need is a piece of wire with a spade terminal at one end, some way of fixing to earth at the other, and a switch in the middle. Plug it into the right terminal, turn ignition on, press button for a few seconds, release button - and the fault codes are displayed on the light.

There's a PDF (8Mb) with _everything_ in it (it's the official Saab troubleshooting documentation), scanned by a guy on SaabCentral. I've uploaded it to http://www.citroencarclub.org.uk/images/c900_lucas.pdf

You can test the AMM easily by unplugging it and starting the car, you'll get a light, but it should run smoothly.

 

[EWealleans]

Hi
thanks; always sounds so blooming easy! I've read the manual you attached and even understand most of it (electrics always fox me, but the mechanics of it are quite straight forward). However, not sure it is Lucas. The tech2 was attached to a relay in the off-side wing accessed by lifting up the back seat. Is there a quick way to identify which system I have? I don't want to fault-find until I know for sure.....
Thanks
Ez

 

[mark e]

Is there a quick way to identify which system I have?[/b]

The AMM on a Lucas is all aluminium construction- the Bosch is more plastic, notably the input and output collars.

Lucas cars also have a large gold wirewound resistor about half way up the inside of the drivers side wing.

The connector on the inside wing is the one you would need to connect to to pull the codes.

 

[TooMany2cvs]

The AMM on a Lucas is all aluminium construction- the Bosch is more plastic, notably the input and output collars.[/b]

Even easier - the AMM on a Lucas says "LUCAS" in big letters...

Ez - the AMM is on top of the air filter box - stand by the NSF wheel, and you'll see the intake trunk "peering" over the inner wing. Look forward of that, and there's a black plastic tube heads over to the turbo. The AMM's just under there.

Lucas cars also have a large gold wirewound resistor about half way up the inside of the drivers side wing.[/b]

That's the easiest way!

 

[EWealleans]

Hi guys,
well it's a Bosch! Everything is labelled thus. So, I think it's the LH.2.2 version. I'm presuming that the fault finding is different because of this. Will check back as sure someone has detailed this system somewhere before.

I am curious about this:


"You can test the AMM easily by unplugging it and starting the car, you'll get a light, but it should run smoothly" I haven't mastered the quote function....

What exactly am I testing here? Is it the fact the AMM is working or NOT working......

I've ordered a new cat ( more flipping money), can't believe the rattle and roll this things producing aint going to affect performance especially if there's blow back.

Thanks for any advice - I WILL get this sorted...
Ez

 

[TooMany2cvs]

Hi guys,
well it's a Bosch! Everything is labelled thus. So, I think it's the LH.2.2 version. I'm presuming that the fault finding is different because of this. Will check back as sure someone has detailed this system somewhere before.[/b]

Have you got the Bentley workshop manual? It covers Bosch in detail - since that's the only engine management they got in the US. There's usually copies on ebay - well worth getting.

I am curious about this:
"You can test the AMM easily by unplugging it and starting the car, you'll get a light, but it should run smoothly" I haven't mastered the quote function....[/b]

Just put [ quote ] before and [ /quote ] after the bit you want to quote - but without the spaces inside the square brackets.

What exactly am I testing here? Is it the fact the AMM is working or NOT working......[/b]

If the AMM is giving _real_ hassle, it should run smoother, as it'll default to sort-of-about-right settings instead of listening to the AMM as it lies like a politician.

 

[EWealleans]

Ok disconnected the AMM and the revs shot up to 1500, where it stayed; switched off, cranked and idle now at 900. Is it safe to assume the AMM is doing it's job?

If so, the AMM is fine, the TPS has been cleaned, the fuel injectors have been replaced - where next (she still sounds rough but not hunting). I need to get the cat on....
Ez

 

[Orca]

'alright EZ! Have you cleaned out the AIC valve with carb cleaner?

To be fair, the fault codes will tell you where the problem is - it's worth retrieving the codes anyway since not all of them trigger the CEL. Similar issue with ours and we ended up replacing the AIC valve due to hunting and stalling problems if idling and the cooling fan kicked in or the windows were opened - that kind of thing. The other thing that is intermittent on a mate's car is the lambda sensor - he'd had a period of intermittent CEL and rough running. When I disconnected and re-connected the lambda sensor, it got better. Maybe just remove, clean and clean up the terminals on all the major FI system parts?

 

[EWealleans]

Sounds like good advice Orca - started with the dizzy today and will do air filter tomorrow - cat's being done next week and I'll clean all Fuel system connexions as suggested, especially the AIC.
Cheers
Ez