stauren1203

iTrader: (1)

Long story short, I just bought my FD. It has 33600 miles on it. I drove it home nearly a thousand miles and I drove it all this weekend with no problems at all. City driving, Highway driving, "spirited" driving. Having never owned an rx7, I've been keeping a KEEN eye on the oil levels and all gauges and pretty much everything I know to look for.

Anyway, this morning, I was driving to work. As with all of my other cars, I let it warm up about 2 minutes before actually driving away from home. The for the first 5 or so minutes, I take it very easy, not accelerating past 2500 rpm. I was going up a hill, and the car started to feel bogged. I thought to myself, "maybe this is similar to my s2000 in that it HATES low rpm. Traveling about 35, I downshifted from 4th to 3rd. When I released the clutch pedal, the car lurched pretty good and the check engine light came on. Again, not being overly familiar with RX7s or rotaries, i panicked. I immediately pulled over and turned the car off on the side of the road. I called my wife but she didn't answer. I had to get to work so I turned the car back on and the CEL was gone. I drove it pretty easy the rest of the way. As I got closer to work I was curious to find out what "state" the car had to be in in order for the CEL to come on again. As I saw a clear turn off ahead of me, I slowly pressed on the gas pedal until the CEL came on again. 3000rpm. This time the car didn't lurch but it DEFINITELY felt bogged down and would NOT rev past 3000. Turned the car off then back on again, no CEL present. I completely babied the car all the way to work, and searched here for what this might be. I didn't find an answer to what the problem is, but I did find this "solution."

https://www.rx7club.com/3rd-generati...00-rpm-421397/

My question is, and I am asking here instead of on that thread because all other forums I belong to frown upon reviving dead threads, IF there is a greater problem than just being in "limp mode," do I run a risk of causing more problems by clearing the code?

dwb87

iTrader: (22)

Possibly. Pull the code(s) before you start freaking out about what could or might happen.

From there, you or someone else may have a better idea of where to start looking in order to completely fix the issue.

RGHTBrainDesign

First off, with ANY turbocharged vehicle, NEVER turn off the engine immediately after running the car. Let it idle for at least a minute, no matter what the scenario. This allows time for the oil to recirculate through the system and cool the turbo. Unless of course you want to be a coked-turbo-head. Cokeheads = No no for me at least.

I would suggest resetting the ecu, letting the car idle for 20+ minutes without throttle (zero accessories/radio off for 10 mins, turn a/c on full for 3 mins, heater on full for 3 mins, a/c again, heater again, radio/set clock), and once done inspecting everything, drive differently. That car NEEDS to be driven. It's not a commuter, but a sports car. Don't ever let that engine drive around at under 3500-4k rpm.

stauren1203

iTrader: (1)

Under most circumstances, I would always let the car idle before turning it off, but the car had only been running at the MOST, 5 minutes, so I didn't assume it was too hot. Also, are you saying the optimal running speed, even on the highway, is over 4000? Rotaries may be more different than I thought :P

Sgtblue

iTrader: (16)

The turbos are water cooled. Unless you're pulling off the race track or autocross course, idling before shut down isn't needed. Doesn't hurt a thing to be driven around at 3.5k.

LIMP MODE, as the name suggests, is designed to get you home while avoiding or minimizing damage. It cuts timing and fuel if vacuum isn't present in the intake manifold. Not all CEL codes will put you into limp mode, so what ever it is, I wouldn't drive it anymore than necessary until it's sorted. My first guess is that it will be one of three codes associated with the OMP/MOP (Metering Oil Pump).

Engine ECU (Reference page F-20 of the Workshop Manual)
With engine OFF, short "TEN" to "GND" terminals in the diagnostic plug (located on LH engine bay wheel well near battery). There is a "map" of the plug terminals located inside the plug lid.
Turn the ignition switch ON, but do not start the engine.
Read any stored trouble codes on the Check Engine light. If no codes are stored, the light will come on for approx. 2 seconds, then go out. If code(s) are stored, the Check Engine light will flash as follows to indicate code number. A Long flash represents the tens digit (10, 20, 30, etc.), and a short flash represents the ones digit (1 thru 9). Example: Long, short, short flash represents code 12. If any trouble codes are found, refer to page F-22 of the Workshop Manual for trouble shooting details.
Cancel any stored trouble codes by turning OFF the ignition and disconnecting the negative battery cable for 20+ seconds. Press the brake pedal. Reconnect the negative cable to the battery. Ref. page F-64 of the Workshop Manual).

1 Ignition coil (trailing side)
2 Crank position NE sensor
3 Crank position G sensor
5 Knock sensor
8 Airflow meter (AFM)
9 Water thermosensor
10 Intake air thermosensor (AFM)
11 Intake air thermosensor (engine)
12 Throttle sensor - full range
13 Pressure sensor - intake manifold
14 Atmospheric pressure sensor (built in ECU)
15 oxygen sensor
17 Feedback system for O2 sensor
18 Throttle sensor - narrow range
20 Metering oil pump position sensor
23 Fuel thermosensor
25 Solenoid valve - pressure regulator control
26 metering oil pump stepper motor
27 Metering oil pump
28 Solenoid valve - EGR
29 Solenoid valve - EGR vent
30 Solenoid valve - split air bypass
31 solenoid valve - relief 1
32 Solenoid valve - switching
33 Solenoid valve - port air bypass
34 Solenoid valve -idle speed control (BAC)
37 Metering oil pump
38 Solenoid valve - accelerated warmup system and air supply valve
39 Solenoid valve - relief 2
40 Solenoid valve - purge control (auxilary port valve)
41 Solenoid valve - variable dynamic effect intake (VDI)
42 Solenoid valve - turbo precontrol
43 Solenoid valve - wastegate control
44 Solenoid valve - turbo control
45 Solenoid valve - charge control
46 Solenoid valve - charge relief control
50 Solenoid valve - double throttle control
51 Fuel pump relay
54 Air pump relay
65 Air conditioning signal
71 Injector - front secondary
73 Injector - rear secondary
76 Slip lockup signal
77 Torque reduced signal

stauren1203

iTrader: (1)

Sgtblue, thanks for this information. I did just what you suggested and drove as easy and as little as possible. I ended up calling around and taking to the most rotary-knowledgeable shop in town to have them check it out. fingers crossed.

Sgtblue

iTrader: (16)

You have a pretty low mileage...and presumably original FD. Take good care of it, there aren't that many left.
While you're having the shop figure out the code, I recommend you read through the FAQ stickys in the 3rd Gen. Section. There are some critical things that should be taken care of on original, low mileage cars....often called "reliablity mods". Have fun.

stauren1203

iTrader: (1)

I'll check it out now. I've read a few things such as the larger ground cable. It is all original Thanks for your help. Appreciate it.

stauren1203

iTrader: (1)

Update- mechanic ran diagnostic. He found codes 26 and 27. According to him, that means either the metering oil pump is bad OR the wiring to the pump is bad. Apparently this is quite a bit of work to do if the pump needs to be replaced (not to mention the pump is over $2000 for the part alone). I'm praying that it is just the wire.

TougeSpirit

iTrader: (12)

Over $2000?!!?! These guys are really trying to hose you.

stauren1203

iTrader: (1)

That they are. I've decided that as long as they have the car, if it's just the wire that's gone bad, I'll have them fix it. But if it's the pump, I've got a good friend who knows rotaries and he's offered to help me out with it. Being that it isn't an internal issue, I'm more comfortable tackling this kind of stuff.

Sgtblue

iTrader: (16)

They aren't necessarily trying to "hose" anyone. A new pump is outrageously priced from MAZDA. Fortunately, good used ones are readily available. Check the 3rd Gen Parts for sale section or go on-line. If you're able, PM a member named Fritz Flynn. Long time member of this forum and trusted source. If he's got one he'll price it fairly.
The 3rd Gem OMP is an assembly. Despite having three separate codes AFAIK, it's separate components aren't designed to to be replaced separately. You can check continuity, but after that it's really just R & R IMO.
It is a PITA to change with the engine in the car, but not impossible, even for us "amateurs" ........

https://www.rx7club.com/3rd-generati...my-how-675341/

If you do it yourself, get a replacement 'O' ring for the base of the pump as well as new copper crush washers for the OMP line to pump. Probably < $10 total. And be gentle (as possible) with those OMP lines.

TougeSpirit

iTrader: (12)

At the very least, a good start for familiarizing your self with your car would be to check out the service manuals for our cars, there are a few websites that have them uploaded " https://docs.google.com/folder/d/0Bz...hl=en_US&pli=1 "

And to check out some of the faqs for fd3's, they have a ton of good info containing lots of the most commonly and not so commonly but good to know answers to questions in them if you haven't already. I'm new to fd3s too

RGHTBrainDesign

Oil inject. Pump Adpt


I think it's time to build a 2-stroke reservoir kit. Cost savings, added protection to the engine, and the possibility of longer oil change intervals with thinner oil if that's a route you were willing to take (I wouldn't personally).

Sgtblue

iTrader: (16)

^It's a great idea, generally speaking. But packaging for that reservoir, especially with a stock or near stock car is really, really difficult. The OP will still need a replacement OMP and with that adaptor, you absolutely can't forget to keep it full.

stauren1203

iTrader: (1)

I am definitely just going to be replacing the OMP. I don't want to modify the car at all. Until the part gets here and I have a chance to replace it, will the car be safe to drive lightly? Should I add premix? I only need to drive it about 40 more miles until it can sit to wait for the new pump. I just REALLY don't want to risk screwing anything up.

XLR8

iTrader: (52)

You need to understand something here. If you plan to own and drive an FD and want to keep things healthy, reliability mods are an important part of that.

-Premix (OMP delete or premixing with operational OMP)
-Downpipe
-Power FC (and viewing commander for proper gauges)
-Aluminum AST or deleting AST
-Aluminum radiator
-Silicon Vacuum hoses
-Efini Y pipe
-Greddy hard pipe kit

These mods aren't taking away from your mint low mileage car, they are rectifying some of Mazda's long term oversights. You need to inform yourself of your FD. It is unlike any other car with a whole lot of special needs. Of course, you can choose to stick your head in the sand and let a shop fix every little problem and remedy the inevitable big problems. But I warn you my friend, you are going to be writing a lot of big checks.

Sgtblue

iTrader: (16)

XLR8 mentions some of those reliablity mods I alluded to earlier that really should be done...even on low mileage cars....although I have a slightly different take on a few of them.
IMHO if you want to replace the coupler from the 'Y' pipe to cross-over with a good quality silicone coupler it will be fine. Same with the GReddy hard pipes. The stock accordian ones last a long time at stock boost. And the stock ECU is fine IMO as long as you remain near stock with stock boost levels. Years ago they used to talk about a 'three (performance) mod rule' before needing a standalone ECU.
The others I absolutely agree with. Especially installing a downpipe. In the unlikely event that you still have a pre-cat on the car, get it off. It robs performance, it's like having an oven set on 'high' under the hood to bake everything made of rubber and plastic...and in a worst-case senario it can collapse, plugging the main cat and costing you an engine. If you have emissions, you'll still pass without a pre-cat.

As for hurting your car, IIRC the OMP will default to 5v, so it should still be injecting something. The rate just won't be load or rpm dependent like it should be. Hence...limp mode to keep things safe. But...if it gives you some peace of mind, add 1/2 oz. of 2-cycle oil per gallon of gas that you have in the tank until you get it where it's going for the OMP replacement. You might smoke a bit, but it won't hurt anything short-term.

Tem120

iTrader: (5)

I wouldnt drive the car as far as you can push it without the OMP UNLESS you premix ( which is effectively the same thing as the OMP . My OMP stopped working as well . and i've been premixing just fine its better for the engine. if you can put up with doing this little tedious task i'd say eliminated the OMP .

But if you aren't ok with it . I'd Premix to drive it where you need to , and Id get it fixed asap .

stauren1203

iTrader: (1)

I got the car back and put in about 12oz. of 2-cycle with a full tank of fuel. At this point, it is my understanding that with the premix, my engine is more than safe. My question, however, is this - how do I tell my ecu to stay out of limp mode? I honestly have no problem running premix for the time being. I just don't want to risk messing anything up.


**note, even with me running premix for the time being, I still have every intention of replacing the OMP. I just want to be able to safely drive my car until then. I apologize in advance for being such a ****, and thank all of you for your patience.

Sgtblue

iTrader: (16)

You can't avoid limp mode on the stock ECU. The ONLY way to get out of limp without replacing the OMP is to spend $1000 or more on a standalone ECU...which you don't need otherwise. Just replace it (see my link above) or have your shop replace it.
You really didn't need the pre-mix. As I said, the stock ECU defaults to 5 volts, which means the OMP is injecting oil at max, even though while in Limp Mode you can't load the engine and it's VERY difficult to take it to high rpm. But the pre-mix won't hurt anything short-term....and I understand peace of mind and err'ing on the side of caution.

Tem120

iTrader: (5)

what if the OMP itself is whats bad ? he said that the mechanic told him the code ment the OMP was either bad or the wiring was , what if its hte OMP itself thats bad and not passing sufficient oil , Like you said peace of mind is a big thing

Sgtblue

iTrader: (16)

As I recall the OMP sensor works on a 1v to 5v...with 5v being the signal for max pump output. As I said, when it or the motor fails, it fails in the 5v/max output setting. Just like other sensors...such as your IAT etc. So while in failure, it's output is at maximum all the time rather than being adjusted for load and rpm as it should.
And besides, HE'S IN LIMP MODE. Your not suppose to drive the car in limp mode any more than necessary. It's so you can get it home or to a garage and not leave you thumbing for a ride. NOT to drive around indefinitely.
Besides, Limp mode won't advance timing and cuts fuel the moment vacuum isn't seen in the UIM. So, as the OP can probably attest, you have no power and it can take you 5 miles on a flat road just to get to 40 mph anyway.
If he has to drive it a few miles to the shop, OK throw in a little two-cycle. Won't hurt a thing. But MAZDA didn't expect you to jump out and do that along the road. I was hoping to give the OP some peace of mind that just because he didn't add it the minute it went into limp that he had done any damage.

stauren1203

iTrader: (1)

I love all of this advice. Honest, it puts me at ease with some folks telling me CAREFUL!!!!!!!!!! and others telling me that its OK to go home, and such. As of now, I have a new OMP ordered, I have a near-full tank of gas with about 12oz. of premix, and the car is stowed safely in my garage waiting for the part to come in Once I get it, I will be driving approximately 20 miles (will probably take an hour to get there) to a friends garage where we will be replacing the pump.

Seriously, thank you guys for your help/knowledge/advice. It's given me much peace of mind.

AjaxOfTheRockies

With all due respect, I've driven FC turbos (two different ones) over the last 15 years and never did the warm-up cool-down stuff. Never had a turbo fail either.

Just my experience. (could be just an "RX thing"...i have *no* experience with other turbocharged vehicles)