ok guys i have been having this prob for about 2 months now and i have thrown way to much money at it to continue throwing money at it i have an 88 t2 a n333 ecu large streetport walbro255 three inch intake so i ran the codes on it it came back as the pressure sensor so i got one it ran just fine once again for about a day so i took the fcd off and it idled like crap so i plugged it back in and idles just fine now but it will go to about 6 grand and hit a wall but it does it all over the rpms it weirs like one time it will do it about 4 grand then the next it will be around 6 grand im at my wits end and its killin me not being able to figure it out and the comp is good 115 both faces thanks guys

 

Sounds like possible bad grounds or a bad sensor. Check all your engine sensors to see if they are withing spec especially the AFM and coolant temp but do check every other one. Get the FSM and go through all the emissions/fuel section. Check for vacuum leaks, if you have any it will "idle like crap". Finally go through the electrical harness and make sure all the connectors are connected and that all the wires are in good condition, and again, check all your engine bay grounds.

Make sure you have the "restrictor pill" in the pressure sensor vacuum line. Then if you still can't get it to run right, come back here and report on your results. The last thing to check would be for clogged injectors and lastly a bad ECU if it isn't anything sensor or wiring related.

 

I would check all the grounds first

 

so there is some kind of valve or somthing thats supposed to be in the vacumm line to the sensor? i changed all my vacumm lines and didnt relize that? does it really make a difference if i dont have the "restrictor pill"?

 

The car will start and run, but the ECU will notice alot of fluctiation from the pressure sensor due to the restrictor pill not in the line and a code will be thrown up (on s5's at least). I think when I was missing mine, it just ran a tiny bit more rough than normal, but this was on an N/A and my engine doesn't go over 100kpa...

You can get one at your local auto parts store, its usually in the vacuum line "T" fittings section.

 

So i checked all grounds there is no restricter pill still need to check some sensors but the afm is good and the tps has a dead spot in it which one is the coolant temp sensor.

 

Did you check the ground under the intake manifold that goes straight on the block?

http://www.aaroncake.net/RX-7/grounding.htm

Get the restrictor pill, you will keep getting codes for the pressure sensor if you don't.... Water Temp Sensor is located behind the water pump near the alternator area...

If you haven't done so, go through the FSM. Your issue may be fuel delivery related. I would suggest you first make sure you can get the car to run properly with the FCD not connected to the car. If it's not idling right with it not connected something is obviously wrong.

The FCD should tap into the boost sensors outputs to trick the ECU into thinking there is less boost than there really is, so if someone didn't connected it properly then obviously something is wrong between the boost sensor --> FCD ---> ECU. If there is anything wrong in that chain, your car will run bad. I am willing to bet that is the issue. Fix the car without the FCD, then run it with the FCD.

http://www.teamfc3s.org/info/articles/fcd/diy_fcd.htm

 

Ok i disconnected the tps today it runs alot better without it bit still alil ruf so im guessin my tps is way gone and it has a black connecter so i believe its an na tps so i have one coming tomarrow that has the white connecter so hopefully that works

 

So what do u guys think

 

I would wait until you get a new TPS that works before going forward. You also stated that when you disconnect the FCD the car ran rough... thats not right either (assuming you had the pressure sensor connected). See my previous post once you get your new TPS hooked up and the car doesn't run well with the FCD disconnected.

Set the TPS to 1Volt using the backprobing method or TPS light (can be found by searching) and re-check the new one for deadspots. From what you have posted so far it seems you are narrowing the problem now...

 

Aight can do buddy thanks for your help im finally gettin there i think and hope lol

 

my s5 gxl doesnt show a code for the presure sensor.

 

Your experience may vary.... I had it throwing codes every once in a while... The pressure readings fluctuate a lot quicker without that restrictor in the line...

 

Ok i got the new tps in today and yet it still doing it i tried to find a restrictor pill and can not find one anywhere what does it look like and how do i explain it to the people they keep acting like im dumb or something lol

 

Though mine looks different and is made out of metal.

 

Could my boost gauge being tied into the vacine to the pressure sensor be causing it ro do this and im going to post a video later today so yall can see what its doing

 

Go to advance auto parts, go into the vacuum "t-fitting" section. It's called a vacuum line restrictor. Will look like a white small vacuum tube with a gold-ish small diameter fitting on one end and a regular plastic opening on the other... Straight plastic fitting basically... Attach it as close as you can to the intake manifold....

Did you check the issue with the FCD i posted to you before????

 

couldnt i get a brass hose fitting, fill it with solder, and dril a ~.5mm hole through it?

sorry mines a n/a

 

I supposed you can... I would just pay the $1-2 for the pre-made fitting....

 

ya but the only places i can find it is mazda dealers,mazdatrix, and a few others, wich reguires a shipping charge, ect. the mazda dealer its ~$3and to get it transfered from malloy mazda coast $3.50. it a quick cheap fix and i love making things no matter how simple they are.

 

I'd turn the key to ON, engine OFF and see what the reading for the pressure /boost sensor is at the ECU when you backprobe the wire with all connectors connected. Then compare that with the reading given in CONTROL UNIT in the fuel and emissions section of the FSM.

 

You haven't read all my post here.... You can find this locally

I agree completely with this, it's one of the things I hope the OP at least took a look at already...

 

there is no advanced auto in phoenix and no other auto chain store carries anything even similiar

 

Go into the vacuum line fittings sections, where all the vacuum "t's" and vacuum hoses are at. It will be a straight fitting, with the description I gave before. Most of the time the people working at those stores don't know every single item on inventory. You will find it there, autozone should carry it also.

http://milo.com/dorman-vacuum-tubing...ors-hard-47311

Looks like that. Give them that part number 47311 (doorman) and they also should be able to order it free of charge.