New TPS, TPS error gets back and is running me crazy

[onnaj]

Hello,

I just finished my 7AFE to 4AGE 20V BT swap but from the beginning i have a TPS error, code 41. I've replaced the TPS, installed it with the feeler gauge, but still the same error. When i reset the ecu, connect terminals E1 and TE1 and turn the key in the car it first flashes quickly 3 times, but within a second it's giving me the TPS error.

Checked the wiring and all the voltages are perfect. No resistance between the wires, so that's also okay. What could possibly causes this TPS error?

Can a bad ignition coil cause this?

EDIT: The engine light isn't coming on, but when i connect the terminals error 41 is there.

Thanks

[yoshimitsuspeed]

The 20v has a vaccum controlled dashpot on the throttle to keep the throttle plates from slamming shut. When it's not under vacuum that dashpot pushes the throttle plates open just a little bit. Because of this the 20V will give you a TPS error any time it isn't running. You also have to adjust the TPS with the dashpot retracted so either with it idling or hook up a vacuum pump to it or mechanically retract it.

[onnaj]

The 20v has a vaccum controlled dashpot on the throttle to keep the throttle plates from slamming shut. When it's not under vacuum that dashpot pushes the throttle plates open just a little bit. Because of this the 20V will give you a TPS error any time it isn't running. You also have to adjust the TPS with the dashpot retracted so either with it idling or hook up a vacuum pump to it or mechanically retract it.

I don't completely understand what to do now? I understand when the car is not idling there isn't a vacuum but it's normal to check the engine codes with the engine not running? And i checked the codes with a running engine anyways, haven't done that on purpose but i did it today. Still code 41. It's the only one i get.

Hope you can help me out, it's really frustating that my car isn't running okay and running waaaay too rich.

Thanks.

[yoshimitsuspeed]

When you adjusted the TPS did you adjust it with the dashpot retracted? If not then that's the first thing you need to do. I also saw your other thread about the three wire TPS. You need to figure out if your ECU has a pin for the idle circuit. If it does then you will need to run a wire from there to the TPS.
If not or if that doesn't do it then do the on car tests in the BGB and check voltage at the ECU on the TPS pins. Make sure everything checks out where it goes into the ECU. If that does check out then I would start suspecting your ECU.

[onnaj]

Hello,

I didn't retract it i think. Don't know exactly what the word means. Should i just disconnect that pot (@ the throttle lever )?

This isn't said in the manual btw.

Thanks

[yoshimitsuspeed]

Like I said, either adjust the TPS with the motor running, hook a vacuum pump up to the dashpot or retract the actuator. Retract means to compress the spring and make the actuator short enough that it is not contacting the throttle plate.
This should be obvious when you are looking at the ITBs. There should be a hard stop that the throttle plate should rest against when it's fully closed. This hard stop may have an adjustment bolt on it, I don't remember for sure.
Then there will be the dashpot with a little actuator arm. That arm has a spring on it that pushes the throttle plate away from the hard stop. When the car is idling the vacuum is greater than the spring force so it sucks the actuator in and makes the throttle plate rest on the hard stop. This is where it must be when you adjust the TPS. To get it to rest on the hard stop you can put the dashpot under vacuum. Or you could probably use something like a clamp or zip tie or something to compress the dashpot enough that the throttle plate rests on the hard stop.
Admittedly I have never looked at this part of the 20V BGB to see what it says. I just had to figure it all out on my own when I was getting my motor dialed in right.

I use a different method to adjust my TPS. I like it better though some think it's silly. All I know is it works and I feel it's quicker and easier.
I loosen the TPS screws to where the TPS spins with some resistance. I start the car and watch the CEL through the back window. Turn the TPS one way and the CEL goes on. Turn it the other way and the CEL should go back to blinking it's no code blink. You must turn the TPS very slowly at this point as it will take the ECU a second to register changes on the CEL.
With the car running turn the TPS just until the CEL goes off. Snug up a bolt so the TPS won't turn. Get in the car and ever so lightly step on the gas. Let the RPMs rise slowly. If the CEL trips between 200 and 400 RPM above it's warm idle then call it good. If the code trips at less than 200 RPM above idle then spin the TPS in the direction that you were before to make the code go away. If the RPMs raise more than 400 RPM before the code triggers then rotate the TPS in the direction that triggered the TPS code on. The one thing to be aware of is that at this point you are trying to rotate the TPS fractions of a mm or fractions of a deg. You want to spin it so little you can barely tell it moved.
Repeat this procedure till the CEL triggers 200-400 RPM above warm idle.
If you can't get the CEL to go off while it's idling then something is wrong with the TPS, the signal getting to the ECU, or the ECU it's self.

[onnaj]

Thanks for your great and long reply, i really appreciate it.

I do have a few questions, hopefully you're able to answer them for me.

1) I adjusted the TPS with a feeler gauge of 0.8 and 1.0 mm. Isn't that a bit the same as retract the actuator arm? This prevents the arm to press it. Or does it press even harder when inserting a feeler gauge?
2) When adjusting it 'your' way, should i jump TE1 and E1 on the diagnosis box?
3) My TPS is turned almost max counterclockwise and then i had to move it a few mm clockwise to get non continuity with the 1.0 mm feeler gauge and continuity with the 0.8 feeler gauge. How is yours? Mostly clockwise or mostly counterclokcwise?

Thanks again!

[yoshimitsuspeed]

Thanks for your great and long reply, i really appreciate it.

I do have a few questions, hopefully you're able to answer them for me.

1) I adjusted the TPS with a feeler gauge of 0.8 and 1.0 mm. Isn't that a bit the same as retract the actuator arm? This prevents the arm to press it. Or does it press even harder when inserting a feeler gauge?

Just to make sure we are talking about the same parts.
This is the actuator located inbetween the throttle bodies.


This is one of the hard stops. Each TB has them and when the dashpot is retracted each one should rest on it's hard stop.
As you an see in this pic the dashpot is holding the arm a couple mm off the hard stop.

2) When adjusting it 'your' way, should i jump TE1 and E1 on the diagnosis box?

Yes that is correct.

3) My TPS is turned almost max counterclockwise and then i had to move it a few mm clockwise to get non continuity with the 1.0 mm feeler gauge and continuity with the 0.8 feeler gauge. How is yours? Mostly clockwise or mostly counterclokcwise?

Mine is pretty centred but slightly to the counter clockwise side.

[onnaj]

Thanks again!

I put the feeler gauge between the actuator stop and the idle adjustment screw. Is exactly that thing you showed on your picture. I'm going to adjust it this evening the way you did it. So hopefully the error will go away.

Yesterday i measured the voltage at the ECU connector and the voltage is allright, so it must be either the wiring (didn't change the wiring btw, used it from my old 7AFE cause it's the same) or just still the TPS that isn't adjusted well.

I'm also going to look if all the TB's rest on the stops!

thanks for all the info, i'll keep you updated!

[onnaj]

I did it your way without succes

I've ended up measuring the voltages at the ecu. The voltage from VC to E2 is 4.8V or something like that, so that normal. But the voltage between terminals VCA and E2 is also 4.8V with throttle closed, but with with WOT it's 0.00V. With the throttle closed it should be between 0.3 and 0.8 and with WOT between 3.2 and 4.9. Somehow the ECU turns it upside down?

Is this a ECU failure?

Do you measure voltage between VC and the VTA connector? I measure around 2.8V there with ignition on. With ignition off there's nothing.

I've measured the resistance between VC and VTA, VTA and E2 and VC and E2 and it's all infinite. Between the VC @ the TPS connecter and at the VC @ the ECU it's 0, same counts for VTA @ TPS and VTA @ ECU and E2 @ TPS and E2 @ ECU.

EDIT: Because we turned the TPS it might not be exactly in position...i think this will have influence on the voltage of VTA wouldn't it?

I did notice also did when turning the TPS nothing happened to my engine at all, no differences in idle or so.

[yoshimitsuspeed]

Are you sure your IDL and VCA pins aren't switched around?

Let's step back a little bit.
At one point you said you only have 3 TPS wires right?
And you are using your old 7AFE wiring?
First we need to confirm you have the right number of wires going to the ECU. First, does the ECU have a pin for IDL and 4 pins to the TPS? If so do you have 4 pins on the TPS and 4 wires going to the ECU?
If so then are you sure the TPS is pinned properly for the ECU? Some TPS are very similar but tend to have a couple pins switched or be backwards in reference to top to bottom or in reference to the locking clip.
Make sure it is wired right and that the ECU is seeing signal for all the pins it is looking for.

[onnaj]

Problemtha most certainly solved! The 7afe connector has the pins exactly reversed regarding the 4age connectorsconnectors. So codes are gone now time to enjoy i hope

Really thanks for all the help!

[onnaj]

Drove about 50 km and the code didn't reappear.

Also set the ignition timing at 10 BTDC, it was at about 8 BTDC

Still running much too rich, cause i have some backfires in low rpm range, but that might be the oxygen sensor. That had a hard time at the first starts up with all the oil etc burning. I have a spare one though .

So any tips regarding the rich running are welcome

[RW Bliss]

I just got my bt 20v running as we'll, and it too seems to run rich. Backfires and I can smell
A lot of unburnt fuel thru the exhaust. Hopefully someone chimes in on pointers. I'm running
Oem ecu, COPS, tweak harness, T3 stacks/uni filters.

[yoshimitsuspeed]

Backfires can be a sign of running too rich or too lean.

No one ever takes me up on this but you can tap into the O2 signal in the diagnostic connector or back of the ECU and actually see what the O2 sees. It will only do any good at idle and light cruise telling you it's running at stoich as it should or to tell you something is really wrong like it running lean at WOT or something.

[onnaj]

Backfires can be a sign of running too rich or too lean.

No one ever takes me up on this but you can tap into the O2 signal in the diagnostic connector or back of the ECU and actually see what the O2 sees. It will only do any good at idle and light cruise telling you it's running at stoich as it should or to tell you something is really wrong like it running lean at WOT or something.

In my case i can tell for sure it's rich. I smell the fuel in the inlet manifold. When starting sometimes it runs very rough for a second or 2, after that the engine runs fine, but rich.

Maybe tomorrow i'm going to check the O2 sensor as stated in the blacktop manual.

[onnaj]

I've measured the o2 sensor today and the resistance is perfect. I also checked if the voltages changes more then 8 times when i connect the TE1 and E1 connector and with the voltmeter between VF1 and the E1. And it does, so the o2 sensor seems to be perfect.

I also noticed that a start with a warm engine is diffcult, while when the car is cold it starts alsmost before i turned the key It's runs smooth right on. With a warm start then it sometimes seems to run on 3 cylinder for a few seconds.

I've also checked the spak plugs today and they are all nice. In the beginning they were all black, but now the engine has run about 300 miles after the rebuild they are all nice and all the same.

My bet would be a leaking injector, but how can i best test this? Grab a bowl, disconnect the injector from the rail, connect it again with the bowl underneath it and see if the spraying pattern is nice?

What else could cause this?

Thanks!

[yoshimitsuspeed]

Did you watch the O2 sensor readings without the diagnostic connector jumpped? If it is bouncing back and forth across the .5 volt middle mark I would say everything is working right. It should bounce between something like .2 and .8 volts give or take a couple points.

[onnaj]

I've only checked it with TE1 and E1 jumped. This is how i should do it regarding the manual. When i don't connect TE1 and E1 and just measure VF1 and TE1 its stable at about 2.5V i think.

Should it also jump without the TE1 and E1 jumped?

And how should i check it then? Just put a voltmeter between pins VF1 and E1 on the ecu diagnosis?

[yoshimitsuspeed]

I forget which pin you need but you want the signal wire coming from the 02 sensor. You should be able to measure from there to ground. It sounds like you have the BGB so it should be easy to figure out which wire that is in the diagnostic port or on the back of the ECU. Pos from the DMM goes to that wire and neg can just ground to chassis. It would be best if you ground to the same place your electrical grounds to for the ECU.
At idle this output should bounce just above and below .5 volts.

[onnaj]

I think i should be able to measure it at the diagnosis connector, won't i? That'd be easier than in the car on the ecu

[yoshimitsuspeed]

I think i should be able to measure it at the diagnosis connector, won't i? That'd be easier than in the car on the ecu

Yes, if it's all wired up correctly. I have started adding the ECU pin as an option since a lot of people with swaps don't seem to wire up the diagnostic connector. If you are feeling fancy you can run a wire from there to the cabin and monitor AFRs through your DMM while driving.

[onnaj]

I did keep it, already thought it might be handy I like to keep it as oem as possible.

Going to try it with the cable.. .good idea

I might have a little exhaust leak, can that also cause such a rich running?

[yoshimitsuspeed]

I did keep it, already thought it might be handy I like to keep it as oem as possible.

Going to try it with the cable.. .good idea

I might have a little exhaust leak, can that also cause such a rich running?

I did mean to mention that earlier. Good you brought it up. If you have a big enough leak before or even shortly after the O2 sensor that allows air to get into the exhaust stream it will make the ECU think the motor is runnong lean so it will add fuel to compensate.

[onnaj]

I'll also check that. But i'll doubt it, cause cold starts are almost perfect...just a split second it runs rough, but warm starts are more difficult.

I'm going to change the injectors to see if that makes a difference. Hope that either today or tomorrow i have some extra time for it

[onnaj]

Can a bad vibration insulator cause the rich running? I've changed them all when i've cleaned the TB, but i already thought some were a bit on the big side.

Now i've dismounted the injectors again and i've noticed the upper and down injector vibration insulators are different in size. The upper one is a perfect fit but the lower one is a bit bigger. Do you guys think this can cause leaking or vacuum?

Thanks again.

[yoshimitsuspeed]

On an AFM system intake leaks would cause a lean condition if anything.
Wit MAP it would just cause a high idle. It shouldn't effect the AFRs at all.

[onnaj]

But can the injector itself leaks fuel when the lower insulator isn't a good fit?

[onnaj]

I did check the O2 sensor yesterday and it seems to be fine.

When i'm at idle or rev in neutral the voltage bounce from i think it was 0.2x and 0.8V.

I still suspect the injector vibrators insulator. But hope someone can tell me if they think they can cause a leaking injector?

[yoshimitsuspeed]

I can't imagine a way the insulators could cause anything unusual like that.
I would trust the O2. It can be hard to tell if a car is running rich just by look, sound, smell etc.
If the O2 looks good and the plugs look good that says a lot. At least about closed loop cruising. There could be an issue with open loop but that will be hard to really diagnose without a wideband. I have been wanting to put a rent a wideband together but haven't gotten around to it. I should finish it up one of these days.