HAILERS

***And Hailers, I was thinking of you when I played around a bit while the meter was on the O2 sensor****

You'll be hearing more from me about that. It just ain't so in my observations. It has a lot to do with rpm. If I remember it's around three grand in fourth that the closed loop drops out. Like I said, later when I have time to give you figures. YOu sure your 02 is working all the time?

WAYNE88N/A

I was at about 3K when I tried it (twice), maybe a little higher...I thought we could go closed loop in fourth, also, so I wanted to play with it...

I have seen nothing yet that would convince me that the O2 sensor is kaput. I've watched it so much over the past 6 months or so that I know its tendencies, and sure as $hit, it was the "tool" that nailed my problem for me. It was reading stoich the whole trip home last night (5th gear), and it was "dipping" during the problem bumps. The only question in my mind was whether it was lack of fuel causing the "dips", or something wrong with the O2 sensor itself, causing the ECU to fritz out on the injectors. The test that nailed it for me was disconnecting the sensor for a while, and still getting the problem...

I've still got it hooked up to keep an eye on the FPR, since I won't have parts for a couple of days, so I'll try it again in 4th gear (I can't stand driving that slow, though )

WAYNE88N/A

All righty, Hailers, I think I see what you are referring to as closed loop. Technically, using the definition of "closed loop", it is, but I don't consider it closed loop (just want to be fiesty today, lol)...

Had a couple more "events" today, and during each the O2 sensor was going wild. The fuel pressure starts dropping (due to the FPR sticking open, I'm hoping), the sensor voltage starts dropping, the car starts her "thing", and the ECU tries its *** off to bring up the fuel- I can see this all happening on the meter, as it's happening. Pretty cool, actually...

Okie Dokie, now to the closed loop thing- I'm not attempting to win a "civil discussion" here, understand, just sharing my thoughts...In 5th gear, during closed loop, I get nice, precise meter bounces between .4 and .5v, approx 4 times a second...In 4th gear (and 2nd & 3rd, I've found), the meter displays what is obviously a "closed loop", but the range of fuel corrections is much wider (.4 to .7v), and the frequency of corrections is about half that of 5th gear, or in other words, it's half as fast as the 5th gear closed loop...I choose to consider this normal ECU fuel scheduling, not a closed loop operation...

Another scary thought entered my warped mind as I was driving- what if the FPR is good, but the vac source is the catalyst for the problems. Every bump, something in the vac routing system "opens", killing vac pressures, and freaking out the FPR, which in turn freaks out the fuel rail pressures, that kind of scenario...That would be a sum biatch to track down. Or is it just paranoia? Been troubleshooting this thing way too long...

hondahater

iTrader: (2)

you should get rid of your vac rack, that would take care of that problem!

HAILERS

P.....a......r.......a.......n.......o.........i.. ........d

WAYNE88N/A

Lol, that's all I get?

I was expecting a long list of facts & figures purporting proof that a closed loop could be accomplished in 4th gear...

I've been waiting all day for that

Seriously, I want to know if you were successful in getting the .4 to .5 in 4th gear also...

DerangedHermit

Holy dear god, this whole thread has me sooooooooo confused.

WAYNE88N/A

Lol, I basically started it to list the troubleshooting steps and conclusions, so that someone in the future wouldn't have to go through all the bullshit I'm going through...

FPR causing hesitations- who'da thunk it???

phinsn98

iTrader: (2)

Wayne if you've read my post on this you might see that my problems all started when I was replacing the FPR. It was leaking so we ordered a new one and put it in. In the process one of the injectors locked up when re-starting the car. I replaced the injector with a new set of RC Engineering injectors for the primaries. The car was pig rich and I was lost about 20 miles per tank. Shortly after water started passing into the combustion chamber (completely different issue) In the process of the rebuild I decided to replace the factory harness on the ECU side with a brand new one. Car has never run better, it's idle is smooth with the AC on or off. The only major problem was and still is the hesitation. We tried a new TPS, AFM, boost sensor, swapped injectors, checked for vacuum leaks (found a big one), changed the angle of the airflow meter, new water temp sensor, grounded the car and even put the old harness back in. NO DIFFERENCE...still have the hesitation. Fuel pressure was checked and as far as I know it was nominal. The only thing I didn't do was replace the FPR (hell it was new). Let me know if this resolves your problem because it might be my next request to resolve this problem.

HAILERS

****Lol, that's all I get?*****

Dear Paranoid,
I've been busy doing other things. I have a wideband that I use on a daily basis and I see 14.5......14.8 all day long in forth, if the car is held on a steady speed below about three grand. That's from memory. I'll look harder in the next few day. I tried to connect my SAFC to the 02 sensor as is suggested on several posts. They say connect it to the Blue wire and read the 02 form the SENSOR Voltages in ETC. Sorry, I find that inaccurate. The incoming voltage at idle is....say .65mv...but the SAFC reads more in the .55 range. I have three good meters and they all say .65mv but the SAFC says 5.5mv. I'm starting to have doubts about SAFC voltage figures. Serious doubts. Then there's the oil filter adapter that installed under the oil filter, much like the one from MAZDATRIX but homemade (one inch thick piece of aluminum ....bandsaw....drill.....tap outfit). I installed a water temp gauge sender in it to read/compare oil temps b/t cars. Then there's the K-type thermocouples I got last week that I installed in my intercooler inlet and outlet hoses like in my other car so I can compare inlet/outlet temps b/t one car and the other without having to unhook the thermocouples from one car to the other (set for each car). Then I finally set the KNOCK sensor output/input to the SAFC (I've no idea how it works, by the way). Then I plan to hook the meter to my primay injectors and see how high I can get the duty cycle to go. I've seen the high eighties and low ninteys in the past. Then late at night I've got to read some NZ replies to see if I can find some fault in one of them.....to make my day. Don't worry Mr Paranoid, your day is a coming (4th gear 02).

WAYNE88N/A

phinsn98- Damn, you're just throwing parts at it, lol...Between Hailers & me on this thread, we've described this "mini" hesitation of mine all well as we could- yours is exactly like it? Do bumps affect it? Also, I'm not running "pig rich", as you are, my problem is running lean (especially on the bumps). Like I said a couple of posts up, it got to the point I was reading 0 or .1v on the meter running down the freeway at 70 mph. That was the day I took the FPR off and sprayed it out with some contact cleaner, and tapped it (in line with the spring direction) on the table a couple of times. After reinstalling it, the next drive went beautifully, and the next two, with only minor "incidents" on the big bumps. The O2 sensor is telling me she's finally running again like she's supposed to, so, I"m pretty sure that's the bad boy (she's parked now as I'm on vacation- won't have parts until next Fri at the earliest, I'll let you know how she does).

Hailers, this is really no big deal to me, I'm averaging 27-28 mpg, and she's looking good in 5th as far as the O2 sensor goes (when she's working right, lol), so I'm not very concerned about a "closed loop" in 4th. I'm hardly ever cruising in 4th. Besides, your SAFC voltages sound nothing like my "poor man's" O2 sensor voltages- how to compare? It does crack me up that you're sweating .1mv (you do mean milli-volts, right?). You just might be the paranoid "king" here, lol...I know you like to tinker with things, so you'll go through with all of this anyway, and that's fine by me. It sounds like you like to throw a lot of gadgets on the car, while I just need the essentials (sure could've used a fuel pressure gauge through all this though, lol). Don't forget you might have to shield the thermocouple wiring, if they're anything like the ones I work with, you're playing with really small voltages there...I couldn't get my primaries to go much beyond about 65%, give or take. I wasn't romping full out at the time, but pretty close. I just might have to read those puppies out again one of these days, when all of the problems are gone.

Oh, the "paranoid" thing was a just a little joke, but I see you're having some fun with it at my expense...

HAILERS

Decimals are such small things. Sometimes I like to elevate their place in the world.....at my expense.

Someday I'm gonna depin the 02 wire at the ECU and make a jumper to 2D, then while driving around at a steady mph in forth, break the connection and see how the display changes. Gotta cut the lawn, put out the garbage, fix the house etc first.

WAYNE88N/A

It's not the decimals themselves that are small, but the operator's mind putting numbers BEHIND the decimal, and then using a quantifying term such as "milli" in conjunction with the decimals. A milli-volt is .001 of a volt, so .55mv would be .00055 of a volt. Is this really what you meant? That's a hell of a calibrated meter there, lol...Add the fact that that you typed 5.5mv (instead of .55) later on in your little essay, and you'll begin to see why I told you not to pursue your little quest to prove your "4th gear" point- it doesn't matter, and, we'll never get good numbers for comparison since the little decimals "dots" are kicking your ***, lol...

HAILERS

Ok. The SAFC shows .550 v and the actual input from the 02 sensor is closer to .650 v which makes the SAFC suspect for accuracy

Now.....where was that thread dealing with switching solenoids that Wayne was....mistaken on. Gotta go find that one.

hondahater

iTrader: (2)

you know I'm glad someone brought this up. because I adjusted the tps by way of ecu however on my safc it was way off. Would this mean that the safc sees differantly than the ecu??? It shouldn't if all you are doing is tapping into the tps wire at the ecu... Strange.

WAYNE88N/A

Ahhh, now that makes more sense

So we're being paranoid about .1 volt instead of .001 volt- that's a bit more understandable...

NOW the numbers sound more like an O2 sensor output...

You really enjoy this tit-for-tat thing, eh?

There was also another thread about the BAC and ABSV that I screwed up on, just last week. Look that one up and add it to your archives for future ammo, too, lol

WAYNE88N/A

Honda Dude- just for troubleshooting, disconnect the TPS input at the ECU, and see if the SAFC numbers change...We're dealing with such small voltages here that if the SAFC and ECU sensing circuits aren't "impedance matched" (for lack of a better term), you'll get different outputs. How far off are the numbers?

Don't read the meter like Hailers does, or you'll be getting ridiculous numbers like .00055v...

It might also be a wiring problem on your part

hondahater

iTrader: (2)

no I couldn't have done anything wrong, lol. I believe when I set it for 1.08v at the ecu the safc read something around .895volts. I'm going to check this again with the 1,000 other things I have to do to get this car up and runing by next weekend. It's funny I've always made goals in my life and usually can obtain all of them however with my car I've never met one of them, lol.

WAYNE88N/A

Yeah, you're having the same kinds of problems Hailers is...I've never dealt with any SAFC's before, so this might be a stupid question, but- do you still NEED the ECU input, if the SAFC is doing all the work now?

hondahater

iTrader: (2)

I would emagine so however I am probably just going to hook my safc to the boost sensor instead of the tps the way it should be. Is the safc doing all the work?? I don't know what would happen if you just unpluged or cut that line going into the ecu, good question.

HAILERS

Well I just took a look at the SAFC reading on the pressure sensor, 2B and it was 1.15v. Then I backprobed 2B at the same time and got 1.25.

Now it may not matter much on the normal use of a SAFC. BUT.....it has been written on this forum, that if you use the BLUE wire of the SAFC and connect it to the 02 sensors output wire, that then you can see the 02 reading on the SAFC if you go to Sensor Check and read the voltage there on AF2.

Normally the Blue wire is not used on a RX-7. That wire is meant for use by cars that have two afms.

So what I'm getting at, is it might be just fine to look at 02 sensors output with a digital meter on the dash, because it WILL be accurate. But if you use the Blue wire on the SAFC to observe 02 readings.......it's toooo far off for me. We're talking about a reading from .000 to 1.000 V. So if I read with a meter and see .650V but the SAFC reading on AF2 is .550V....you just have to agree that is far too much of an error.

So now answer this question: Yesterday I decided to set up the KNOCK sensor on the SAFC. Followed the instructions to the letter. So someone tell me what I am to look for when I'm driving uphill, full throttle in third and forth gear? I mean say I have the SAFC right there up on the dash with only the KNOCK showing on the display. When/if the engiNE knocks, what will the display show?

hondahater

iTrader: (2)

man I didn't even know you could do that??? Cool ****! Please someone chime in!

HAILERS

If you do a SEARCH on this forum, and put in the words BLUE AND WIRE, you'll see several hits. Many have squat to do with SAFC. Others mention SAFC in the title. Also if you go to the SAFC section in this forum you might see the ref to the blue wire and reading the output of the safc in ETC.....Snsr Check..or whatever it calls it. I did it yesterday out of curiosity. I don't need it. I have widebands. BUT I'm thinking of connecting the Blue wire to some other output that runs b/t 1 and 5 volts. Like the TPS since I'm using the pressure sensor for throttle on the SAFC.

WAYNE88N/A

Guys, the only thing I can think of is that the SAFC has to process the O2 sensor input first, before displaying it, and your .1v is lost due to the impedance characteristics of the internal circuit. As long as the SAFC "knows" it's dropping that .1v before actually using the signal for fuel scheduling, you're OK...If not, you'll always be running .1v rich (if, by assumption, the SAFC is trying to hit .4 to .5 also for a "closed loop")...

I would definetly prefer to read the signal on a standard meter- it's designed to display the voltage accurately, without inadvertently altering the signal due to processing the signal...

Honda Dude, once you attain proficiency "playing" with all of the ECU inputs, and knowing what to expect from each input, in different conditions, then you can tackle the "cool" things that Hailers is toying around with...Just make sure you understand what "mv" means on the meter when reading voltage

Rex4Life

Wayne, don't know if this helps at all but here's 2cts.

I re-wired alot of the 88 T2 harness and took some good notes while I was at it. I have the CAS shield penciled in on my FSM ECU drawing (pg. 50-22) cause it wasn't shown. I show it going from the CAS connector to FE-02 B/W connector, then to a ground by the ECU.

Whatever you do, don't ground both ends. If you do ground loops will be induced into the shield wire and this is bad. One end must be grounded and usually it is the measurement (ECU) side of the circuit.

Good luck and don't give up hunting this thing down--you'll get it.

Scott