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Discussion Starter #1
Quick straw poll...

How many of you have suffered component failures after fitting an ECU upgrade (or MBC)?

In my case, a few weeks later, it showed up a bunch of vacuum lines that needed replacing.

What about you?
 

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Speedparts Stage 2 ECU fitted in January this year, no problems since.... *crosses fingers*

Thinking about putting in silicon hoses all around, though, in any case. Then again, "if it ain't broke, don't fix it."
 

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Check engine light for open loop fault of EVAP purge valve. Valve works fine so there must be a ground fault somewhere. This might not be related to the ECU upgrade though.

Eric
 

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I had a hose blow off after the upgrade on my Aero, but it was my own fault - I'd forgotten to tighten the clip properly but the standard boost pressure wasn't enough to blow the hose off.

I also had one of the "new" 9-5 type bypass valves destroy itself within three days. The old type, as originally fitted to the 9000, has given me no problems at all.

Maptun did warn me that the increased power output might show up problems that wouldn't show up under normal conditions. For example, a DI cassette that was on its way out would be more likely to show symptoms of failure under the increased boost pressure. That doesn't mean the upgrade caused the failure, but that it highlighted an existing failure that was not apparent before the upgrade.
 

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I did have a major suspension failure after getting my ECU upgraded. I just did not see that massive hole infront of me quick enough
. If he car had been fitted with the "standard" ECU, it woud have been far slower, thus giving me a bit more time to avoid that hole .
 

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on hindsight (always a wonderfull thing ) I guess my turbo grenading was down to the ecu upgrade and more significantly the mbc .however the turbo had done 160k and 40 k after it had siezed for the first time
I guess I got about 20 k at 1.4 bar of boost ...
 

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No problems for me after my custom Hirsch ECU. Unless, of course, you count the even greater thirst for fuel at WOT!
 

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DI and Vacuum lines.- possibly a set of spark plugs.

Possibly not attributable are 2 exhaust boxes.

other bits that will be changed soon that are down to the upgrade are tyres and Rubber bushes

cheers

Alyn
 

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Ok, I think this is a good time to slot in my current problem - this was my reason for joing saabscene! (please see old post 'overboost')

Have Saab 9-5se 2.3LPT. Aero wheels and kit.

Engine broke (oil starvation to No.3 big end bearing).


Bought and fitted 10,000 mile Viggen engine and turbo (9-5 Aero engine basically).

Had my 2.3LPT remapped to, apparently, 275BHP
(remapped Aero performance).

Took it for a blast, started to cut off engine at 3,500 RPM in 3rd, 4th and 5th on full throttle.

They have tried to remap it several times and still can't solve the problem (it only stops cutting out when they drop the PSI).

The car drives absolutely spot on on the standard LPT ecu map.

Anyone any ideas?

ps. it's not a well known saab tuner
 

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Total guess, but it would seem to me that the high psi is causing a knock at peak torque under WOT (which would be around 3.5k rpm) and the ecu (APC) is sensing this and pulling back the boost, ignition etc to save the engine from itself.
Nick.
 

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JimmyJims, I didn't realise your upgrade was still giving you grief. Isn't it time to get your money back and call one of the recognised Saab tuners?

Cheers

James
 

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I know diddly squat about remapping ECU's but it could be the fuel cut off valve being activated when a certain boost pressure is reached. Under standard ECU operating conditions the boost would never get high enough to activate the cut off, but if you reprogrammed the ECU to give higher boost and didn't change the cut off valve trigger pressure you could have problems.
 

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Yes, it is still giving me problems.

If I was offered a refund I would snatch it up, but they haven't offered and are determind to get it sorted - plus I can tell they wouldn't offer a full one. I'm just going with the flow until the stress and anger builds up again and I'll sort it out period!

To my knowledge everything is the same as the Aero appart from ECU, engine and turbo - and I have the engine and turbo so it must be the ECU!! (Leon, your the man with the bottomless pit of part no etc, is there anything that could be different - APC thingy? or fuel pressure cut-off valve? Saying that, you guys are running LPT a high boost and you have no problems...)

I'm going to check pipes etc this weekend but as I've said, the car runs mint on standard ECU map.

Is there a way to test wastegate/actuator to see if it's working properly? (again this came with the turbo and engine).

yours,
a confused limp excuse for an Aero!
 

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On Trionic systems, I believe the overboost cutout is handled by the Trionic software itself. I know it is on T5, and assumed T7 was the same. There is no separate pressure switch and a remapped ECU should have an appropriate pressure limit programmed into it.
 

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Originally posted by BillJ:
[qb]On Trionic systems, I believe the overboost cutout is handled by the Trionic software itself. I know it is on T5, and assumed T7 was the same. There is no separate pressure switch and a remapped ECU should have an appropriate pressure limit programmed into it. [/qb][/b]
Yes, that's correct.

Jimmy, there are two possibilities as I see it

1. The mapping is wrong
2. The output driver for the APC solenoid has failed.

The frist is entirely possible if it's not a well known tuner. If possible, you should get hold of a Tech 2 diagnostic tool and hook it up. That way you can at least get a representation of the APC drive signal that the ECU is generating (one of the functions of Tech 2 is to enable you to make real time recordings of various sensors etc). It is possible to record two outputs simultaneously, so I would record the intake air pressure along with the APC signal. If it shows that the APC signal is working (ie as you approach max boost, it should be opening the solenoid) if it doesn't, then they have mapped it incoprrectly. If it does, then there's probably a component fault in the ECU.

HTH
 

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Jimmy,

You say you've a viggen engine?
This should be mechanically similar to the Aero lump, same turbo, obviously the ECU is different, but it is only software...
And I can't see any specific differences in sensors, actuatorsor anything like that..

So the engine runs sweet on lpt ecu..
How about getting them to throw in an uprated LPT programme, not Aero?
 
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