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Discussion Starter · #1 ·
Hi all, just baught a 9000 aero 97 MY, which the last owner had a stage 1 maptun fitted. The question i have is, that the car seems very sluggish low down, it takes till 3k rpm for the turbo to really boost into the red, at 3k or below, it boosts midway in the yellow. Is this normal with this upgrade?

Any help appreciated.
Thanks
Chris
 

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Hi Chris and welcome

Firstly, the gauges aren't calibrated so the position of the needle is only really a guide to boost.

The Aero turbo is a bit bigger than the rest of the range, so it can be a bit sluggish. However I would have expected a bit more life out of it below 3000rpm.

It's probably worth disconnecting the battery for a while then performing an adaption run- as detailed in BillJ's Saab 9000 Website (link at the bottom of the page).
 

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Discussion Starter · #3 ·
ok, ill give that a try tonight, but there is no kick in the back below 3000, the gauge stays exactly half way up yellow, no matter how hard the pedal is pressed below 3000
 

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The characteristics of the Maptun ECU are not a crude "kick in the back" like some others. Rather, it is progressive and smooth acceleration.

Also ensure that your wastegate actuator is attached and there is some pre-load on it.
 

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Chris, you didn't say if anything else, besides the Stage I, was done to your 9000. If only the software was changed, and you have the original downpipe, then it's no wonder that you get no response below 3k rpms. If the downpipe was changed, make sure that a calibrated gauge is used to measure base boost. Often times, when fitting a larger downpipe, the base boost will have to be re- adjusted upward. Reprogrammed software should only be used after intake and exhaust restrictions are relieved. It's not only better in terms of volumetric efficiency, but also in terms of heat - even the stock Aero engine develops quite a bit of heat (EGT's). A less restrictive exhaust will not only give you a bit more power, but also provides insurance in healthier engine operating conditions.
 

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Discussion Starter · #6 ·
sorry for sounding stupid, but can you explan what you mean by "pre-load on it".

P.S The car is very fast once above 3000 rpm
 

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Discussion Starter · #7 ·
Hi Robert. Everything else is standard. It ONLY has a stage one maptun. The only other info i have on it from the previous owner was that the solenoid at the radiator was renewed, and the base boost turned down as it was over-boosting and cutting the injectors out.
 

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There's a spring in the waste-gate actuator that is pre-loaded when attached to the waste-gate. I agree with what John says about MapTun software - it's very refined, and tranny friendly. However, there should be some boost below 3k rpm. I had MapTun reprogram my ECU, and I'm using the same TD04-15T, yet I had 1.1 bar of boost at 2200 rpm. My peak boost (1.65 bar)occurred at 3500-4500 rpm and only tapered down to 1.2 bar near the red-line.
 

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Well, the first thing I would do is check, with a calibrated gauge, exactly what your base boost is. It should be around 6 psi. Sounds like someone adjusted it too low because of a bad BPC. Put a gauge on there and if you want the full-effect from the MapTun software, I'd seriously consider a 3" downpipe, removing the snorkel, and adding a few more holes to the air filter container.
 

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Originally posted by chris-edinburgh:
[qb]the base boost turned down as it was over-boosting and cutting the injectors out. [/qb][/b]
Ah, there may be a clue here... the overboost cutout will most probably be as a result of the faulty solenoid, not too high a base boost. If the base boose has been adjusted to be too low, then I think this may be the problem as it would cause problems in the the lower rev range. It's definitely worth getting it checked as a first measure- it should be 0.42 - 0.48bar/6.0 - 7.0psi.

[edit] crossed post with Robert- but we agree anyway
 

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Discussion Starter · #11 ·
Hi robert, i think u may be right as the previous owner did say that he just had the gearbox re-built, so didnt want too much torque to blow it again.
So maybe take it to a maptun fitter get them to check the software.....
You mention bad bpc, what causes this????
i had read that the injectors cut out at 1.5 bar?? is this true?
 

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Discussion Starter · #12 ·
bubbles.
You could be onto something here!!!!!!
Can i ask a very silly question, where should i connect a boost meter and i take it you can route it through the car to check when your driving??
 

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Overboost cutoff is around 1.65bar IIRC.
Stage 1 should not be too gearbox-unfriendly at all.

"Bad BPC" is the solenoid you were taling about.
 

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There should be a spare stub on the intake manifold to attach the gauge to. Failing that, it can be teed in to any of the small bore pipes attached to the manifold except the one going to the manifold pressure sensor located on the bulkhead in front of the driver.

For a quick measurement, just route it through the window. If you want a permanent fitted calibrated gauge, you can tee it off the pipe at the back of the instrument cluster.
 

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if you are struggling I would take it into tim @roseisle cars in dalkeith ..
he knows what he is doing around these things
(his boss has a maptun stage 5 that tim built for him...)

but it sounds as if the base boost is holding things back...
 

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I would agree with JOhn my 93 Maptun Stage 1 (plus other bits) is very smooth you look down at the speedo and think oh whops im going a bit fast !!!!!!!!!!!!
 

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you should not have to adjust base boost for a stage 1.

I have a stage 1 maptun on my 2002 9-3 SE (aero)
and it hit fuel cut also. Turned down base boost really far, and it still hit fuel cut. Turns out they forgot to program in the higher fuel cut for stage 1, so they fixed the software and I fixed the wastegate back to normal, and it pulls harder than a frieght train


This is on an autobox, too! I notice the same as others have reported, if I put the gas down hard you don't feel the kick in the back quite as much as when you do it at lower speeds, but look at the speedo and you will realize you are going too fast and wonder how that is possible it happened so quick.
 

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Discussion Starter · #19 ·
UPDATE!!
Ive just checked the base boost as per billj webpage, at it appears to be at 0.3 bar......
My question is, should the ecu be disconnected after the actuator rod is adjusted??
 

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There is no need to disconnect the ECU. Just adjust the wastegate to ensure correct base boost and Trionic will readapt.
 
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