EA82Turbo..throttle position sensor

subybrumby · Post by **subybrumby** » Sun Sep 04, 2011 9:35 am

Hi everyone..Happy fathers day.....

I finally got into my stinger ECU on this car and as I have said it has a flat spot when you drive through the acceleration range.

We are still hoping that someone will look at the car in toowoomba and feel more confident now that we know the ecu is not locked.

The throttle position sensor on our computer that we hooked up to the car is showing that at rest the value is 0%. as you move the throttle thru its travel it then shows 100% and half way thru shows 0% and then 100% at full pedal. Would this be right....is it a variable resistor or a switch. It may be some of my problem perhaps?

Thanks..Trev

steptoe · Post by **steptoe** » Sun Sep 04, 2011 9:43 am

some are just switches like the three plug ECU with a certain angle, differing between turbo and just mpfi ? or was it a difference between Oz turbo and overseas turbo?, the 4 pluggers are variable I think.
How many wires on your TPS - three or additional two or three coming out the side in addition to the three in TPS unit?

subybrumby · Post by **subybrumby** » Sun Sep 04, 2011 10:35 am

There are three wires..we tried to run a multi meter over it last nite but were getting unreliable readings. The computer screen on the program I have for this computer says..0%....then 100%.....then there is another 0% readout halway thru the range of the throttle then 100% at full stick. sounds like it might be faulty. I did a google search and the symptons match up to my problem ie flat spot on acceleration and hesitation on some throttle positions. Prob needs a clean or somethin????

I was looking thru google and there is a 4pin which appears to be a variable resister giving more precise position indications. Another search I found says this one I have has closed....open and wide open throttle. O% shouldn't be at halway???

steptoe · Post by **steptoe** » Sun Sep 04, 2011 10:58 am

you got PM Trevor

RSR 555 · Post by **RSR 555** » Sun Sep 04, 2011 3:10 pm

I might have a 4pin MPFI one if you need one but not home for another 3 weeks

subybrumby · Post by **subybrumby** » Sun Sep 04, 2011 8:02 pm

Thanks Paul...Still working the problem...still hoping for a guy in Toowoomba to look at it. We are just glad that we can access this EMS stingers ecu. Thought it had locked us out. Having difficulty trying to get a mechanic/technician to look at it. They bail when they find that the car has an aftermarket ecu.

FujiFan · Post by **FujiFan** » Sun Sep 04, 2011 9:00 pm

Trev I read with interest the problem you are having. Have a look at this installation manual extract from a popular brand of aftermarket ECU:
The Throttle Position sensor must produce a voltage between 0 and 5 volts,
proportional to the angle of the throttle plate. Switch types are not suitable.
Throttle sensors generally have a dead band at either end and must be preloaded
to avoid the dead band.
The Setup Parameters TPHI and TPLO must be set to indicate the fully
closed and fully open positions. These parameters must be set any time the
sensor is moved or replaced. It is very important to set these parameters with
the butterfly in exactly the same place each time.
The resistance element inside the sensor may wear due to vibration in high
performance engines, this can cause erratic readings. It is best to replace the
throttle position sensor periodically.
Avoid high pressure washing as this may penetrate the seals and damage the
sensor.

J

discopotato03 · Post by **discopotato03** » Sun Sep 04, 2011 11:45 pm

The early TPS unit that only has the one rectangular connector doesn't have a variable resistor that can give a 1-5 volt output . All they have is two switches to tell the basic computer when the throttle is closed and when the throttle is more at a high power opening place .

You need the TPS from a later EA82 MPFI engine , the one that has I think three wires out the side leading to a round plug connector . If it hasn't got this its the early one and won't do what you want .

A .

steptoe · Post by **steptoe** » Mon Sep 05, 2011 8:23 am

The 85/86 manual actually calls this component a THROTTLE SWITCH, not a throttle position sensor!

It has an idle contact and a full contact

This may be whole reason the PO sold the beast - unable to sort its issues if your Stinger requires the continuous and increasing voltage signal.

If you can report back with the part number on the little black casing of the switch, someone should be able to help what is what , or not what you want to fix problem.

subybrumby · Post by **subybrumby** » Sat Sep 24, 2011 12:40 pm

Well, the car has finally come out of a tune thanks to 6boost, Toowoomba, much appreciated. The flat spot appears to be gone, performance is good but having had the trouble for so long I thought I may get more grunt out of it.

The car wouldn't start after the tune and as we had been having a little muck about with it beforehand, apparently my son (the 13B rotor nut) left the check box for the TPS highlighted. Anyway, the guy turned the TPS completely off and the car just runs off the MAP sensor (Vacuum) apparently. With the five speed box, you have to drive it, but its a fun drive.

Jamie (The mechanic) said it was showing the flat spot on the tune so he's fixed that, don't know why it was there. I went for a canter around Toowoomba after it came off the dyno and it was ok, 100% better than it was, because it had a real hesitation before.

We then flew down the Toowoomba range and back up and its performance was pretty well as before without the hesitation it had beforehand.

Not big horsepower but fun to drive...Dyno readout below.

[ATTACH]2898[/ATTACH]

steptoe · Post by **steptoe** » Sat Sep 24, 2011 7:22 pm

A while in the making and good end result. A bonus that you got someone local to tune it. So the MAP sensor takes place of both TPS and AFM with your ECU eh?

You really can't expect too much from it power wise as the 6 or 7 psi boost is working on a 7.7:1 comp ratio and is really only a bit of an improve over the carby EA82 or about 9.2:1 so first few pounds of boost are really only catch up.

I bought a turbosmart $30 jobbie off ebay and caught 10 or 12 psi at times - grow little devil horns sort of stuff

The way I sold myself the EA82T - same torque as EJ22

subybrumby · Post by **subybrumby** » Sat Sep 24, 2011 8:11 pm

Yes, he thought that there was something weird with the TPS and it just wouldn't start while it was activated. He said you would need the TPS for tuning for deceleration ????? but in effect this ecu just uses the vacuum to give the engine the info it needs (MAP). I have a suspicion that the ecu may have had a hand held unit attached before I bought it and some of the tuning has been interferred with in that way. The lead for it was still hotwired under the dash and I took it out some time ago when I cleaned up some of the wiring there. Incidently, there was a turbosmart boost controller fitted when I got it but I removed it when trying to sort this stuff out., I read an early post on here regarding these on an ea82T and the advice was not to submit these engines to too much boost. What do you think Steptoe?? Refit the boost controller or leave it?? its showing about 7lbs at the moment.

steptoe · Post by **steptoe** » Sat Sep 24, 2011 9:45 pm

We have Fury who ran his at 14psi and only got into strife on a hot day towing a boat or something. LTurbo Thomas had his as 10, I think a few have said 8 to ten, any higher use an IC of some sort. Factory settings are for longevity i suppose ... I like 10 on mine

NachaLuva · Post by **NachaLuva** » Sat Sep 24, 2011 11:53 pm

I love turbos....

I cant wait to be rich so i can get a really nice turboed forester with custom IC, water spray, blow off valve, etc. Then add lift kit, M/T tyres, etc

Then have some fun....

subybrumby · Post by **subybrumby** » Sat Sep 24, 2011 11:56 pm

No worries....I think it was running about ten when I got it and it seemed to have a bit more punch when it got past that flat spot than it has now. I'll wind it up gradually and see how the tune goes. It has a top mounted IC so that's fine. Cheers.