I have not, from everything I’ve seen the car needs to be fully warmed up to properly check TPS (I could be wrong) and idling for about 10 mins only got it up to 160 degrees

 

I've never experienced limp mode condition, so I can't answer your question. Here's a thread that describes limp mode: https://www.rx7club.com/2nd-generati...e-mode-926212/

You can do an initial setting on your TPS when cold, but will need to go back and readjust once engine's at normal operating temperature. Here's a thread that describes how to set S5 TPS: https://www.rx7club.com/2nd-generati...r-s5-n-739191/

Does your check engine light in the idiot cluster ever light up when the engine is running?

You've got a bank of 5 solenoids at left front of engine next to the PS pump. You might want to try cleaning the electrical connections to each of these solenoids. Be gentle while doing this because the plastic hose nipples often have a tendency to snap off. Suggest leaving solenoid in place and removing one connector at a time while cleaning contacts with sandpaper. I once had a problem on my S5 where these connectors were corroded and were giving me all kinds of engine error codes. Just a thought.

 

Is the fast idle cam on the rear of the throttle body? I’m struggling to understand the picture posted on that thread and assume I’m just looking at the diagram wrong.

The check engine light has been on since I bought the car. The previous owner deleted the emissions and rats nest and I was told that is why. I’m also pretty sure the wire connecting to the O2 sensor was dragging at one point and ripped apart which I’m sure was also causing the light but I’ve never had the chance to get in and fix that. I recently removed my dummy cluster as well because most of it wouldn’t light up and the surround was destroyed. Replaced it with gauges.

I’ll have to take a look for those solenoids you’re talking about and see what I can do with those. If possible can you post a picture of what they look like/where they’re located

 

I got a chance to look again and realized it’s on the back and that the picture on the FSM is upside down.

I also could not move the screw/lever it’s attached to at all, but it’s getting dark so tomorrow after work I’ll hit it with some WD and try again. I’m thinking it’s seized up, could explain why my high idle never shuts off

 

Yes the car should be at operating temp when setting the TPS. However you can check the ohm reading to make sure there are no deadspots / faulty readings when pressing in the plunger (or throttle). Car can be off when doing this.

S5 FSM - Page F1-83



I have an S4 so I'm not entirely familiar with S5 TPS but to check this I believe you should check the full range (?)
1) Disconnect TPS, You can leave it bolted to the throttle body.
2) Connect Ohm Meter / Multimeter to E - D
3) Slowly press in the TPS plunger (or throttle) and check if the ohms increase smoothly to 5k ohms. If you have a digital meter you should press the TPS plunger very slowly or you might miss a fault spot because the multimeter refreshes too slow.
As you're pressing the plunger in faulty might be something like 1k---2k---3k--0 (bad)--4k---5k. Or while you're holding the plunger steady at a position, the ohm reading keeps changing.

Slowly is key. I had a faulty TPS on my S4 that was reading good with throttle closed and open. But there was a small position in-between where the ohms was jumping like crazy, and I determined that to be the cause of some idle issues I was having. I sourced another TPS and it was much better. My faulty TPS I just sprayed the hell out of it with electrical contact cleaner and crimped on a new terminal and it seems to have smoothed out the ohm readings. But I have never retested this back on my car. Just an option to try since TPS can get expensive / hard to find.

Per the FSM page F1-76, the TPS is an input to these items... Fuel Injection Amount, Fuel Pump Resistor Relay, Solenoid Valve (Pressure Regulator), BAC, Ignition Timing, etc.
~~~~~~~
Similar to this, but that is pressing it way too fast to check a 'smooth increase'.

 

I think you should check A-B, too.I like to use like to use an analog meter for sweep tests. It is easier to see drop outs. Thanks for the video.

 

I was able to adjust my TPS using the cold method of holding the fast idle cam to simulate being warmed up using the Banzai Racing LED tester. The TPS Screwed needed moved almost 3/8ths of an inch before being set. however after starting the car it idled around 1000rpm (better than the 1500 its always been stuck at) but would die after about a minute or so. I tried letting it idle several times with same result before moving the TPS screw to around where it was originally. I let the car get up to temp by idling and small throttle inputs for about 20 minutes and set the TPS again properly. The car would then idle around 1000rpm and wouldn't die. The TPS screw moved about 3/8ths of an inch again for this so i assume it wasn't dying anymore because the car was hot. My fuel cut issue was also gone (for about 15 minutes). I took the car out for a drive and on the way into town the fuel cut started coming back so i limped it back home. By the time i got there it was just as bad as it was before and now my revs bounce from 1000 to 1500.

I then tested my TPS. Both the full and narrow range had a few dead spots (One of with being where i think my fuel first cuts out in the narrow range) and areas where the Ohms would bounce like crazy. My TPS had also came unset in the 15 minute drive and i reset it again.

I then was able to pull engine codes using the method Hot Dog had found and they are the following-

#11-Air Intake Thermosensor
#12-Throttle Sensor (Full Range)
#18-Throttle Sensor (Narrow Range)
#20-OMP Position Sensor
#25-Solenoid Valve (Pressure Regulator Control)
#30-Solenoid Valve (Split Air Bypass)
#33-Solenoid Valve (Port Air Bypass)
#38-Solenoid Valve (Accelerated Warm-Up System)
#40-Solenoid Valve (Purge Control)
#41-Solenoid Valve (Variable Dynamic Effect Intake (VDI) Control)

I'm assuming those Solenoid Valve codes are for the solenoids Hot Dog had mentioned because I didn't see anything near the power steering pump. They may have been removed when the previous owner did the rats nest/emissions delete on the car but a picture of what I'm looking for would be appreciated incase I'm just dumb.

I think the next plan of action would be to replace the TPS and investigate code #11 and #20 further, Right? I hope this finally gets me moving in the right direction. As always more input is greatly appreciated.

 

Nice work so far! I am not super familiar with S5's so I can't really help much. With that said, the first four codes and maybe the last one, I think the last one is important for the low RPM range but I really don't know for sure. 20 seems important if you don't premix? The first one will help quite a bit with fuel delivery and timing, I think. You know the other two....

I am sure someone else will chime in. Best wishes, keep up the good work!

Edit: i was mostly wrong about the VDI, it is important to keep for many, though.

 

Interesting. 3/8" is quite a bit, and the TPS shouldn't unset itself just from driving for 15min. It should also have no dead spots and irregular ohm readings.

#11-Air Intake Thermosensor
Probably affecting your air/fuel ratio if this is not working correctly.

#20-OMP Position Sensor
I think on an S5 if there is nothing connected for the OMP, it will go into limp mode. Do you still have an OMP or the connector connected at least?

#25-Solenoid Valve (Pressure Regulator Control)
Are all of your solenoids are gone from your rats nest? One solenoid is for the fuel pressure regulator. If your issue is fuel, something to look into.


If it were me, all the codes would be worth looking into lol.

 

Here's a photo of the S5 N/A solenoid valves. There are 5 of them - 2 on the top and 3 on the bottom.



Is your air pump still on the car?

 

Did some researched and checked my issues in the car so starting with the good-ish news, all the solenoid codes I can ignore for my case.

All the solenoid codes were a part of the rats nest delete and didn't cause me any issues for almost a year and a half of owning the car. The only real issue i have with these being gone is not having the accelerated warm up working properly, however i don't hardly drive the car when it's cold and when I do my foot has made a pretty good replacement. Code 11 for the thermosensor I also think I figured out, the prongs were bent and the plug had come off most likely when i took the manifolds off at the beginning of this ordeal. I straightened the plugs out and plugged it back in, hopefully that was all it needed.

Now for the not so good news

My TPS will need to be replaced, I've found some new old stock on EBAY that I'll probably buy and hope it fixes my problem. I think this is my main issue for all this

Next is the OMP position sensor, it is plugged in and the OMP assembly looks like it had been replaced before i bought the car. I think this may be an electrical issue but I'm going to put it off until the new TPS is installed. I have always premixed so I'm not worried about it, as long as I'm not in LIMP mode which from reading what LIMP mode feels like, I don't think I am.

Wilfff- I do not have the FPR solenoid anymore, instead it was routed from the FPR to a vacuum hookup on the bottom of the UIM. The car had ran fine like this up until now so I do not think this is my issue but I will look into this if the new TPS doesn't fix my issues.

Hot Dog- The air pump is also deleted, however I have a Racing beats exhaust so not CATS to worry about keeping clean. Thank you for the picture, I definitely do not have any of that in my car

 

On an S5, the air pump is used to accuate 5th & 6th auxiliary ports and the VDI (Variable Dynamic Intake). Without these functioning, your performance will suffer.

 

I had a suspicion my 5/6 ports weren't working properly, guess that explains why. Ill need to look into sourcing a new one and figure out how I'm going to hook it back up. I don't have the stock air box or air neck to hook it back up to.

 

After a much needed trip to the Smokies, I'm back with more news.

First, while i was gone my new TPS came in and i got the installed right away. This comes with some good news. Both codes 12 and 18 for the TPS ranges are gone now, I was also able to get the Air intake thermosensor fixed and code 11 for that is gone as well.

Bad news, it didn't fix my issue which now leaves me with code 20- OMP Position Sensor. From what i can tell this is putting me in limp mode which must be my issue and from what I've read this likely fried my ECU. I haven't been able to find anything saying if i can just replace the sensor and I'm only seeing one used OMP on eBay that looks to be in pretty rough condition. I guess its time to pull the ECU and OMP and do some test.

I also checked my fuel pressure regulator and I'm not sure if this is how its supposed to work or not. With the vac line plugged in its stuck at 30psi no matter how high i rev the car. With the vac line unplugged its stuck at around 40psi. From what I've read this is correct but the pressure should also rise with the RPMs unless I'm mistaken.

 

Almost forgot. I now also have code 51- Fuel Pump (Resistor) Relay.
I'm pretty sure this refers to the one behind the passenger headlight that changes the pump voltage and not the one under the dash. If so, I was planning on bypassing this anyways once this was all figured out, but might just do that now. Just hoping for some confirmation on that being what it refers to before i get to cuttin and splicin

I'm sure most are aware but for those who aren't, the S4 NA did not have the resistor relay but the S5 NA does. I've seen a lot of confusion about this in the forums so just wanted to throw that out there.

 

you're correct, the fuel pump speed relay is the one by the headlight/airbox, and is code 51
the one that turns the circuit on, circuit opening relay is the one by the steering column

 

sounds to me like a low fuel pressure issue, i wouldn't be trusting that digital gauge for this. or an incorrect/faulty AFM has found its way to your car.causing it to run severely lean. a faulty OMP should only cause the car to run like it is hitting fuel cut at ~3600 RPMs.


stabbing the throttle resulting in a bog/backfire to me sais it is starving for fuel. it's quite possible you have a leak inside the tank causing pressure to drop during high load situations. changing the pumps resulting in varying results kind of points me to that as a culprit.

you may still have a faulty OMP issue, but this doesn't appear to be that.