GTR Problems HELP I need to feel what this car can do.

[svenspeed]

Yeah it's in an Escort but I can't seem to figure out what is going on. Still stock boost.

Engine used to Rev up and down at the light. Changed the IAT from the escort and still had the same problem. If I block off the VAC line from the IAT it will Idle 800 all day long as long as there is no load for the stepper motor. I got so annoyed with it I turned down the idle with the screw on the TB. Runs like crap at an idle but it doesn't rev...

That is problem 1, problem 2 is when I get any kind of boost engine cuts out and spits and sputters especially at WOT. I wired in the 4 wire TPS. before all of this during the swap on my NA harness along with everything else needed (knock control, resistor box etc).

I think that it is the TPS although I have heard that it can be my plug gap and I have tried a different gaps 40,30,25 (really spits at me then). Engine will not rev over 6K at an idle.

Ok if you don't think that it is the TPS how do I check the VAF to make sure that it is functioning correctly? (GTR VAF)

I need a specific model of plug and what gap you think would be sufficient.

Is the base timing for the GTR still supposed to be 10 deg?

I have the GTR ECU also and all the wires I believe are that as they would have been on the GTR harness.

FPR seems to work also... I plugged it and drive my can and flooded the hell out of it. LOL probebly shouldn't have done that.


This problem has really been killing me, I can drive it around town as long as I keep it under 3500, after that it just sucks.

PLEASE HELP

-Steve

[Lex]

It is not the TPS for sure, car drives fine without the TPS. Are you getting a lean stutter or lots of smoke (rich?)

Plug the FPR straight into the manny and dont run it through the solenoid.

It can be the VAF, it can even be the disty/cap/rotor/plug wires.

Static timing is 10 degrees.

Get the codes on the ECU as well using the following method

Buy LED and appropriate resistor (red = 1kOhm, green/yellow/amber = 470 Ohm). Alternative is 12V dc packaged LED from electronics store.

Make up test lead so it follows this circuit (insulate all exposed wire, leaving the two contacts for the +B socket and the FEN socket, make sure you can see the LED from the drivers seat):

+B socket (12V)

--> Red wire (solder end of wire to make acceptable stiff end to stick in diagnostic socket)

--> Resistor (red = 1kOhm, green/yellow/amber = 470 Ohm)

--> LED - Longest leg of LED (positive)

--> LED - Shortest leg of LED (negative) Wire with stiff end (eg. paperclip)

--> FEN socket (diagnostics)

eg:

+B #------- Resistor -------*----------- LED ----*-------# FEN

(* = soldered join, # = solid end)

Use another insulated wire between TEN and GND on diagnostics socket. Ensure it cannot touch anything else.

To test ECU codes

1. Do above
2. Try/run engine
3. Turn off engine
4. Turn ignition back on
5. Observe LED

Car is OK then LED lights up like the dash lights e.g. for 4 seconds and then goes dark.

Fault code is one second light/ one second dark followed by 4 second intervals for a new fault code. e.g. Disconnect air mass flow meter, run car and you get 8 +1, disconnect timing pickup on camshaft and try and run car then you get 8 + 4+ 1 (codes are stored until you erase them).

6. To erase the codes - make sure you stereo etc is not code protected, then remove battery terminal for 30 seconds.

Note it is also possible to force the fuel pump (F/P), coolant fans (TFA) and have an electronic source for a timing device (IG-) from the diagnostic socket.

There is still the MEM tag -

Note on FEN to +B signal - this will only source 35.7mA maximum current drain so a normal 12V test bulb will not light. I was using the test bulb to drag the voltage up then measuring the voltage of
FEN, it would dip to 11.57V but the scan/refresh rate of my digital multimeter is about 0.5 second hence difficult to be certain of pulses. This practice is strictly dubious - hence the need for an LED
circuit or similar.

[jay]

It's been my experience that these cars are very sensitive about their plugs. Use NGK BCPR6ES-11 on stock boost, BCPR7ES-11 when you start running more than 15psi. Gap em at around .020 to start. If you upgrade the ig. coil you can go to about .029, maybe .030. make damn sure your plug wires are good, just use magnacore or NGK stay the **** away from the other crap out there. I don't know if this will solve your issues, it sounds like the ECU ain't wired up right. I don't think it' sthe TPS. When those go, they either make you run pig rich, or you get real lucky and a loose chunk of conductive crap moves around in there, shorts the signal, which makes the ECU go into limphome mode and you get zero spark above 2000RPM. You can unplug the SOB and it'll still run. So if it'll rev at all above 2k, boost or not, then it ain't the tps. You can always plug a multimeter into it and just look at what the resistance does as you move the throttle, you should see a nice even rise in resistance. If it jumps around or hold steady then moves up fast then the tps has a problem.
Sounds like ignition so go through all that stuff, plugs dist wires cap rotor ignitor... pull the plugs, set em ovber the valve cover, unplug the injectors, and crank it over. You need to see like 3/4 of an inch of spark from the plug to the cover. Got like a half inch or a quarter inch? You have spark issues. Got great spark? Got gas? then it's a gremlin in the ECU wiring, resulting from a frankenstein swap. Been there, done that, have scars, best o' luck. Go through the manual and triplecheck your ECU harness. It's way too easy to get those little bastards mixed up. Use your multimeter to make damn certain the the wire you think is going to a given sensor is actually doing so, don't trust it just looking for the color on the insulator. Don't give up cuz when it runs right you will **** bricks.

[svenspeed]

GREAT!!!!!!!

I will go out and get the plugs today, I have an aftermarket coil, that I will install also that was on the EGT to begin with. NGK Power wires are what is on there now. What should the total resistance be there? Assuming that I have a bad plug wire? I also have an MSD 6AL box that I haven' wires in also.

It never seemed to run rich or give me any smoke of any kind. Could I use the EGT VAF to see what happened? I have heard that I can only run like 8psi with it, but would it work right with the GTR ECU? Doing this just as a way to test things?

For the wiring harness I had it completely pulled apart (nicely) and did the wires one by one from the GTR then adapting them to the NA harness. Not only by color if they were the same but with the schematics from both to make sure that they were the same thing. That was a bit PITA....

I will try a couple things today and see what happenes.

And thanks again guys for all of your help.

-Steve

[therieldeal]

i'd stick with the GTR vaf... try new plugs, cap, rotor, basic tune up stuff as people mentioned. also i would wait till its running well before you try to add the MSD box. good luck!!

[Lex]

The MSD box can cause problems .... like Jon said, don't add it until it runs properly.

[elscotto80]

Are you using the GTR injectors? I think they need some kind of resistor box because they are high or low impeadence (opposite of the GTX). Check that?

[svenspeed]

Yep orange top GTR injectors with resistor box hooked up....

[jay]

If you are still having problems and you suspect a bad airflow meter, beg borrow or steal one from a 2nd gen turbo RX7. it's compatible with your engine and electronics.

[svenspeed]

Can't find one here to beg borrow or steal around here. Goora drive over an hour away to check jy's and hope they work....