INGHAM

I found that my MY99 UK Unmodded car is holding back at 3k+ because its running leaner than a weight watchers sausage !!

Delta dash results at full throtle up to 4.5k;

throt sensor vtage 2.34v
max inject dut cycle 25%
knock correction -1.5
ignit timing 28 degrees
air flow sensor voltage 3.22v

Lamda Reading 1 to 1.1 up to 3500 revs, then it steadily increases to 1.3 at 4500revs (when it should go down).

boost increases smthly to 3200 revs and holds steady at just over .8bar.

I need to ask Subaru if ECU map load point is derived from throttle position or MAF SENSOR?

And does the car have a full throttle swich?

Given all of the above, can anyone answer the questions and suggest which parts of this show the car is knacked what devices or sensors may be at fault. (Had ECU & Turbo replaced by subaru already)...

Help...thanks

Bob Rawle

Do you mean lambda reading as in lambda ie larger is leaner or voltage ie larger is richer ? DD reports voltage for a MY99.
Load is TPS, maf and I suspect, to some extent, map derived.

INGHAM

Lamda reading, not DD. It was the reading on the RR system.

can anyone still answer the other questions?

ta

AndrewC

You say that these readings were taken at full throttle and yet the TPS is only reading 2.34V ?

Either the ECU is getting the wrong voltage from the TPS or the throttle is not opening fully.

Andrew...

john banks

Really a log file would be much more helpful rather than one snapshot. For WOT that TPS reading is really low, and -1.5 degrees knock correct would suggest that the map access is off (could be a result of faulty TPS?)

Check the voltage range of TPS as a first step.

If that is not it, please collect a full load of a run through third gear with all the relevant sensors logged.

Cross posted Andy! At least we agree

[Edited by john banks - 4/23/2003 2:05:30 PM]

WREXY

Ingham,

What are your front O2 sensor readings with Delta Dash? Do a run at full throttle in 3rd gear from 1500rpm to about 6800 and let us know. When you give us the figures we'll be able to tell if it's lean or rich.

Cheers,

Wrexy.

WREXY

Cross posted as well! Agree as well!

Cheers,

Wrexy.

INGHAM

Thanks for all of your replies.

The data logs would need to come from g-force so i will need to speak to them tomorrow when it goes back in. I believe that the
As I was worried about a melt down on RR and as it was so lean, they only went to 5k revs. Hence no 6.8k sensor readings.

TPS voltage was 2.34 but they expected 3.9v

(is 3.9 the correct voltage?).

I think that g-force wanted the questions above asked as all data lead to faulty TPS or MAF...

As I'm going back tomorrow, as well as my requesting the logs, which may not be that easy, can anyone answer the questions (which I have been asked to get from subaru) above and give some expected values under certain conditions which may help?

Thanks.

INGHAM

SUBARU dealer just told me there is no "full throttle switch".
So thats one question not needing answer (if they are right).

For others ref : Throttle position sensor is just called a "throttle sensor" part number 22633AA161 for MY99, £141.57 + VAT.

Answers to remaining questions would still be welcomed. Thanks.

john banks

You would get one much cheaper from Grade A subaru breakers (no connection with them) if you wanted something second hand. They are not common failure items and I wouldn't hesitate to use a used one.

David_Wallis

on your year there isnt a full throttle switch, however you should still see a higher voltage than that at wot.. check the earth to the block.. Ie check for 5v between the supply to tps and the inlet manifold, and then to the battery.. If that makes sense..

INGHAM

stupid question im sure, but can it be dirty, loose, badly adjusted, etc. If so, then how do I locate it? I will have a quick look tonight?

I will also hunt for a contact number for the salvage place....

Thanks yet again.

AndrewC

www.gradea-subaru.co.uk

INGHAM

Thanks 4 lnk.

I would stil like to know if ECU map load point is derived from throttle position or MAF SENSOR?

I presume the "map access" being off means that a sensor is not registering something..

ta. C

john banks

It is a combination of MAF and TPS, with possibly minor contributions from others like MAP which may very on year.

Map access is a term used in Ecutek mapping software which allows you to load up an ECU that matches the one in the ECU to which you are connected and then it shows which 2x2 block is being accessed/interpolated by the ECU on its load vs RPM maps of fuelling and timing. If the TPS or MAF are deficient in their readings the traverse across the map will be less than expected leading to a lean and advanced mixture.

MKC

INGHAM Here (MKC as now at work).

G-Force in Aylesbury have now replaced my MAF Sensor and its like a new car. It has never been like this since I brought it in November 2001.

Thanks to everyone in this post for all of their info.

Below are a selection of figures (at full throttle I presume) as they were AFTER the MAF was replaced :

225BHP. All voltages now as expected. Boost 0.85 bar more or less constant. Thrott Sensor 3.84v, Max inj duty cycle 72.28%, Knock Correction 0, Ignition Timing 17 degrees, Air Flow voltage 4.16v

Meter CP-AIR Flow (part number 22794AA010).
£73.51 inclusive VAT.

I presume that the figures above are about right ?

Thanks again.

Colin.

john banks

Sounds good. TPS is a bit lower than some normally over 4V at WOT, but it is not too bad and I wouldn't worry.

nom

I reckon the TPS could be raised to the around usual 4.1v by simply moving the mat under the pedal a little