Just changed dealers due to franchise issues and have fortunately changed from a mob I didn't trust too much to a dealer who has someone who is passionate about scoobys. Had car booked in for some other work and this guy happened to ask if I knew if the previous dealer had recalibrated the throttle angle for the new PPP ECU. I didn't have a clue. Apparantly it takes 5 mins to check and 15 mins to reset.

Had my car checked and the ECU read 91% at WOT, had all this adjusted properly and it makes a lot of difference (crisper pickup all the way from tickover to max). Having read other threads about disappointments with some PPPs I wonder if dealers failing to make this adjustment could be the cause .

If Mike Woods is reading this perhaps you could comment on the effects of incorrect calibration as it makes my brain hurt trying to figure it out.

Cheers, Diccy.

 

There shouldn't be any need to "adjust for the PPP ecu" as the tps settings are the same and not available for configuration in the ecu, so either its right or not right from the outset, if not right then yes it would make a difference. For example the correct settings for a MY01 Eurospec are tps closed 0.2-1.0 volts and fully open 4.2-4.7, quite wide ranges so any car could need to be optimised under these circumstances not just a car with a PPP upgrade.

Since the tps angle is used by the ecu as factor in load calculation it means that you could be running on an incorrect part of some maps for the actual load being used.

bob

 

Diccy

We have had problems with this in the past where dealers are not following the PDI process. The fitting instructions they have are very clear that they should follow the same process that they would do with ANY new car and make sure that the throttle scaling is done properly. We have tested cars that have only shown a max of 91% throttle and these have shown a remarkable tendency to det as it's miscalculating the load.

Mike

 

Mike,

Ouch ! Thanks for your comments. Glad I've had mine sorted, reading "a remarkable tendency to det" gave me a sinking feeling for a moment, I think I may be lucky to have got away without any apparant damage although I now have a lingering concern about what might have happened. I will never go near the old dealer again.

Mike/Bob,

Between you this suggests this could be a potential problem for anyone PPP or not.

Many thanks, Diccy.

 

As someone with a morbid distrust of main dealers, how can the average owner be sure his set-up is correct in this respect? (Equipment required, procedure etc)
I remember seeing Bob go through this procedure when he mapped the Link in my previous car.
As someone who sees the occasional amber on the knocklink in my 03STiPPP it starts to make you think?
JohnD

 

As Mike says you need to make sure the car is set correctly, since tps is a factor in calculating load point if it reads too low then, as I mentioned, it will be picking the wrong point ie too much timing and too little fuel, I always check when mapping, haven't found any problem cars to date but there's always a first time. Deltadash or a Psi3 will provide the info if you have either, otherwise its a conversation with the dealer but you could check voltages with a dvm, that wouldn't tell you it was right in that car though as the tolerance is wide.

bob

bob

 

Just a thought but if the wrong part of the map is being used due to tps error and causing the onset of det, won't the knock sensor signal cause the ECU to back things off a bit. Accepting that the engine will still not be running correctly will this prevent major damage (ie melted piston)?

Cheers Diccy.

 

I have a Psi3 so please what is the procedure?

Ignition on.Fully depress pedal.Look at TP % reading.

Mark.

 

Mark yes thats right but make sure the car is fully warmed up.

yes the ecu "should" back off however there are boundary's within which it will do this as std and if you are running outside it does nothing.

bob

 

Obviously a Psi3 will tell you the values but has no way of correcting any error! This would mean a trip to the dealer (or a mapper) with the appropriate software to get both zero and 100%
Bob - why would the car need to be fully warmed, I thought it would be a static test? - or are there certain temp. related inputs that the ECU needs to consider and would this also apply to the voltage check? (would not the output V be dependant on the actual input V to the pot? in which case an engine running, on road test would be reqd.?)
Diccy - Reading between the lines you sound like me - a bit of a worrier! I may not use my car to it's full potential very often, but I need to know that it's as it should be.
Mark - Press the pedal and let us know what you see?
JohnD

 

Hopefully not smoke & flames.

Will give it a go tomorrow.

Mark.

 

John nothing to do with temp compensation, the tps sensor is a resitive device and so should be at normal operating temp, also I have noted that the ecu's start from cold with a voltage offset on the tps which is clearly designed to aid cold starting, therefore for "normal" idle setup the car should be warmed through. Otherwise you could be resetting the cold start offset.

bob

 

At the risk of being obvious - the ECU will never pick up 100% throttle angle if the cable won't pull the butterfly fully open .
Check cable slack on a new car after its first 1000 miles and tighten it up before looking at the electrics.
I presume that Subaru garages DO check this at first service??

Nick

 

Bob, Simon,

Do you know what TPS voltage tolerance should be on an euro 04 STi? The 2 I've done have 3.9 and 3.92v at WOT (but still 100% throttle angle, so I don't think it's an issue).

Both have had different problems (reluctance to boost and low MAF output). Probably related to crappy tuning parts already fitted, but have little experience of these cars yet (externally they look identical to 7's and 8's?).

Richard