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Discussion Starter · #1 ·
Well sort of, I suppose I have more of a spool up problem, this is really a continuation of my post regarding the Nordic ECU.

When flooring it regardless in what gear the power that was on tap from 2800rpm has shifted too 4500rpm . This has happened since the first adaption run after fitting the Nordic Ecu.
I hear you all saying "it's the ECU" normally I woud agree however my Speedparts ECU does exactly the same My guess is that the ECU has broken or messed something up, maybe due to too much boost? it was constantly hitting overboost at 1.5Bar.
I had a leak between the d/pipe and turbo, this is now sorted, boost would not hold above 1.0bar, sorted with stiffer spring.
I have changed all hoses including APC hoses and they are all fastened with clips. I have also changed the APC valve with a spare, plugs are fairly new and correct gap has been checked.
I have also removed the induction pipe and checked for play in the turbo shaft, no problems there.

I am not hitting max. boost of 1.4bar (ecu programmed for this amount) until over 6000rpm.
The turbo should spool much faster than the engine but it feels as if it is being held back and spools at the same speed as the rev counter.

I have also fitted (but now removed) an MBC connected directly between the wastegate and turbo compressor, this made no difference whatsoever.

Any thoughts....apart from a new car!

Steve
 

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Have you tried disconnecting the battery for an hour or so, and reconnecting?

Though my experience is only with the standard ECU, the above procedure worked for me when I had a boost leak.

IIRC when the ECU detects a fault condition, it changes the operating parameters accordingly, and may throw a CEL. The TechII will clear a code, but the ECU still remembers the parameters and continually tries to make adjustments even though the fault is no longer there. Disconnecting the battery basically resets it.

Probably worth a try, don't forget your radio codes beforehand.
 

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That's a bit of a brain twister, Steve.

What turbo do you have BTW that makes 1.4 bar at 6000 rpm- that would equate to 350hp plus by my reckoning


If you haven't already, I'd start by checking base boost.

After that, to eliminate mechanical vs control problems, I'd try using a 3 port MBC in place of the APC solenoid and see what happens.

I do however have a bit of a worry that it might be a problem caused by a failed APC solenoid which has damaged your ECUs . Check the resistance of the solenoids- they should be about 3 ohms on each side.

HTH
 

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Originally posted by Steve-Stg 2:
[qb]When flooring it regardless in what gear the power that was on tap from 2800rpm has shifted too 4500rpm      .[/qb][/b]
I had a similar problem when testing a new stage upgrade two years ago. I had no surge in power until much higher up the rev range. This was due to base boost being incorrectly set.

Have you measured your base boost?
 

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Discussion Starter · #5 ·
Thanks for your input guys,

Vincent, I have been swopping the ECU's around between fault findimg so they have both been disconnected for hours and sometimes days at a time.

Mark, I have the T28, just went out and checked my figures after reading your post...yes I'm hitting 1.4bar at 6000, I have a feeling that Nordic may have increased the fuel cut off point if not it could be linked to the problem.
When the boost kicks in at 4500rpm it is so brutal that I have to change gear almost immediatly, when testing earlier I kept my foot to the floor a little longer, I am sure I was at 6400rpm with no fuel cut off I thought it should be somewhere around 6200/6250.
I have tried a 2 port MBC with no sucess, why a 3 port?
"Failed ECU" I remember it well I had chips with my first fried stg 4 ECU, my knackered APC valve killed my stg 2 and 4 ECU's it took weeks of swopping old for new to pinpoint the problem even £98.00 on Tech 2 was no help. Fortunatly Elkparts and Speedparts stood by me until it was resolved, a new stg 4 ECU was sent to me which solved the problem of constantly being stuck in base boost.
I have checked the APC's all 3 are ok

John, Base boost before fitting the stiffer spring at the weekend was 0.4bar and still showed the problems I have, I changed the spring and kept the rod the same length, this however gave me a b/boost of 0.7bar (a bit high) still tweeking and is currently somewhere between 5 and 6....come to think if it, it has not been easy checking with my right foot to the floor I have to press the brakes pretty hard with my left, even then it drops very slowly.
Do you remember if yours was set too high or low when you had your problems?

Sorry for the long rant, Just trying to get all the info in.

On a side note, I should have ordered my next upgrade this week I have decided to ditch the T28 and go for the GT28rs, Just waiting to hear back from a couple of tuners to see if they can do the mapping for me.
Can anyone suggest which A/R I should go for considering the 2.0ltr spools later than the 2.3
should I go for the .86 or .64

Steve
 

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Steve, my base boost was too high when I had problems. I had similar problems at Anglesey in 2004, base boost too high meaning no power until high up in rev range and then all hell broke loose. So did the hose from throttle body to IAC ...but I did not discover that until later
 
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