New Fd RX7 owner. Need help
 

I recently got a 93 rx7 stock setup with Street port. I finally got the check engine light to flash codes and I got 4 codes.
16
28
30
38
will driving with those codes damage my engine

Moved your thread to the new member tech section. You'll get more responses here.

You might want to recheck the codes, I don’t think there is a 16.
28 and 30 are emissions related...EGR and split air bypass valve respectively. No immediate harm to engine, but long-term it might dirty up a stock catalytic converter, and being in CA you probably won’t pass emissions.
38 is Accelerated Warm up (AWS). A lot of owners remove it anyway with a block-off plate. No harm, keeps it from wanting to rev high on cold start...which is actually a good thing. Pretty hard to catch on a visual inspection I would think, but no experience.

Code 16 is EGR Switch (CA Only). Check the EGR switch connector, wiring between EGR switch to ECU, or the EGR switch itself.

I'm sure this link is in the FAQ section but you may want to bookmark this page:
S5 and FD CEL Codes

You should download the factory service manual (FSM), body electrical troubleshooting manual (BEM), and wiring diagram manual (WDM) to help diagnose any problems. The WDM and FSM will help in this situation. Furthermore, these 3 manuals are an invaluable resource in your tool box.

Welcome to the wonderful world of the FD!

Thanks for that correction on code 16. I didn’t remember it and it wasn’t on the CEL list I had.

It's all good! You did most of the heavy lifting. I merely filled in the finer points.

I suspect with the OP's engine setup, the EGR was bypassed. If anything, his car would be far less fuel efficient.

@Don93RX7, are you running stock cats or they punched out? Any other mods to the car? What ECU are you running?

I was told it was all stock minus the street port and looking at the engine bay it seems to look stock. I might pay to pass smog lol idk yet. I do premix. And yea I’m not worried about the aws code. I’ll let it warmup on its own. I believe stock ecu

https://cimg6.ibsrv.net/gimg/www.rx7...cd1a2242b.jpeg
This is the engine bay

Hmmm, street port on a stock ECU? Is your exhaust system stock? Do you still have the pre-cat or have a downpipe? What about cat-back exhaust, is it still stock?

How does your FD run at idle? Does it brap-brap, idle high, stumble or is it buttery smooth?

FWIW, I am not an expert in engine management. As I understand, the car requires a certain amount of back pressure to run efficently. Any engine acts like an air pump. So without balanced pressure, you could develop engine problems much faster than normal. Again, I'm not an expert in that topic!

I hope that others will kindly chime in to offer advice and when needed, correct my assumptions!

I just recently got it but it’s on stock exhaust With cat . I am thinking about getting an aftermarket exhaust but haven’t decided yet. If it’s bolt on I may do it that way I can swap it back for smog test. Won’t be until after I get suspension on it. Idle is around 1.5k

Wow! That's a high idle.

Verify that you have a pre-cat or a downpipe connected to your exhaust manifold. It cannot be seen just by the photo you provided. If you see a bulging pipe connected to the exhaust manifold then the pre-cat is still installed. If you see the same diameter of pipe linking the exhaust manifold to the cat then you have a downpipe. You should also have an O2 sensor connected to either component.

Something to think about when you decide to upgrade the exhaust: you may need to consider an aftermarket ECU, like a Power FC (PFC) + Commander. Hypothetically, if you couple the street port with an opened exhaust such as a downpipe, a high-flow cat, and a cat back system then you should be using an aftermarket ECU. The aftermarket ECU can be tuned to prevent detonation.

Getting back to your original concern about CEL codes, you could ask the previous owner about the EGR system. You could also ask if the stock ECU was modified or chipped. This would help diagnose any other problems you may encounter with the car. The only thing that I would see about those codes would be burning more fuel and emitting more pollutants.

Are there other members who could better advise Don93RX7? @Sgtblue, would you care to chime in, please? Engine management is not my strong suit.

Thanks in that case I’ll wait on the exhaust because both exhaust and ecu would cost me a pretty penny lol. I was thinking about upgrading the cooling. So I might tackle that after the suspension because it’s way to loose. It bounces like crazy. Was going to start looking for some good suspension street use only. Never going to take it to the tracks. And yea idle is high. I was going to mess with it but decided to ask you guys first before making changes like that. I want the idle to be 800-1000 I think that would be a decent idle. Depending how it sounds. Wasn’t sure if aftermarket ecu is needed to change idle

I’m not a tuner. But with that high idle I think I’d get the FSM and maybe start checking the Throttle position sensor and/or Idle air control. If it’s a loping/hunting idle I’d also be looking for a vacuum leak, usually around the upper intake manifold or the gasket between the upper and lower manifolds.
Moving to a standalone ECU does allow you to delete troublesome 30 year old emissions components, but you’re in CA. and doubt it would pass visual or emissions testing.

Probably not directly related to your idle issues but you’re missing the crossover duct that normally runs from the top of your IC duct where it’s been capped with the four rivets, to the intake box. Like that, you’re now sourcing only hot under hood air. Not good for IATs.

Personally I’d focus on the engine issues before moving into exhaust mods but it’s your car, your money.
REALLY old pic of my car when it was close to stock showing the duct I mentioned...

https://cimg9.ibsrv.net/gimg/www.rx7...9dd41e68ca.png

My main priority is making the engine reliable as possible. I don’t need power. I was only thinking exhaust to save the cat but wasn’t going to do that any time soon. So after suspension I was thinking more cooling

Not sure what I’m looking for on your picture. Is it that shiny piece on the left. Sorry for the bad description

Don,

The cross-over duct is the narrow, rectangular object that is in front of the smic (stock mounted intercooler) and air box.

Damn I didn’t even noticed that. I’m going to ask the previous owner if he has it. Hopefully he does otherwise I’ll have to buy one for about $100. Does that cool down the engine?

https://cimg8.ibsrv.net/gimg/www.rx7...3eb8320bc.jpeg
https://cimg9.ibsrv.net/gimg/www.rx7...591d9d5d1.jpeg
Seems to be stock exhaust with cat. Also I’m open to all suggestions that would improve the life of my engine

No, it doesn’t do anything for engine cooling. But sourcing nothing but hot under hood air raises you intake air temperature (IAT) which reduces power and in the very worst case scenario can cause preignition...and on a rotary that can cost you an engine. There’s a simple but invisible modification that can be done to the stock air box to let it source ambient air from the nose of the car. With that, you can leave that riveted plug in the top of the intercooler duct and more air will continue to go thru your intercooler. Better breathing, better IATs, more power, quicker spool-up and invisible to state visual inspection. Search in the 3rd Gen section with terms “cheap bastard”. A member named ‘adamc’ used to make a kit with a little ducting. Not sure if he still does but you can still do the modification easy enough.

Speaking of cooling...that would be my priority above all others once it runs decently. All metal (aluminum) radiator, metal AST which you already have, good solid coolant hoses (special attention to turbo coolant hoses) with OEM clamps, fresh coolant with as much distilled water to coolant as you can get away with safely in you climate but no less than about 20% coolant mix. Clean faces of oil cooler(s) and radiator etc. The car looks like it could use some love.
You can search in the 3rd Gen section for additional cooling mods...but everything pretty much starts there imo.

Not certain but that doesn’t look like a stock main cat to me.
For reference...the stock precat/downpipe on the right, an unknown brand but common looking downpipe on the left:


https://cimg3.ibsrv.net/gimg/www.rx7...6573f8c7ea.png

I agree with SgtBlue, the main cat doesn't appear to be stock. However, the pre-cat looks to be installed. Notice the worm gear clamp around the heat shield in the 2nd photo? It's a little hard to tell given the narrow angles. The heat shield in your photo looks similar to SgtBlue's comparison photo.

I would argue to say the previous owner may not have that cross over duct. If he does and you wish to use it, then you will have to remove the plug on the intercooler duct. It looks to be held in by 4 rivets. If you install the duct without removing the plug then you will cut off fresh air supply to the engine.

adam c is still on the forums. You can shoot him a PM to see if he can fab his "cheap bastard" fresh air intake. The link to his intake thread is here: Cheap stock air box mod

I second SgtBlue's recommendation to focus on engine cooling. A happy rotary is a cool rotary! Do some homework, read up on other threads, and interact with other forum members to prioritize your maintenance schedule. Aside from your suspension upgrades, I'd consider the cheap bastard intake mod and cooling system refresh/upgrades.

As a parting shot, let's not ignore the EGR errors you currently have. If those are not fixed then you will certainly not pass CA smog. If it were me, the closest alligator to the boat would be:
1. EGR
2. air intake
3. engine coolant
4. Brake/clutch system flush*
5. suspension

* - Not previously mentioned but looking at your engine photo, the master brake reservoir has nearly black fluid in it. Brake fluid is hydroscopic, meaning it absorbs water and other particulates. The particulates suspended in that fluid will act like a cutting fluid. It will destroy rubber seals over time. Additionally, the master brake reservoir doubles as the clutch reservoir. That's great to save weight but bad when the same reservoir is contaminated. Simply flush the brake & clutch system using the standard methods and you're good to go! As extra advice, access to the clutch slave cylinder is easiest from under the car. If you have a vacuum kit then bleeding either system is a 1-man operation. Just keep the reservoir topped off! Otherwise, the traditional 2-man operation works well.

I've been meaning to ask, do you plan to do most of the maintenance yourself?

Oh ok thanks guys this is really helpful Information. I’m going to try to pass smog legally but could pass it by paying $150 lol. I’ll go by your list. There was some clunking noise when I drive which I thought it came from the shocks but uncle believes it might be bad bushings or axel. Might have to make that a priority too. I message Adam idk if he provides everything or I’ll have to get the fresh air in duct cover or whatever it’s called. Yea yea I’ll have to do the maintenance and my uncle would help a lot too. Don’t see any rotary shops around me. Uncle has a lot of experience with piston engines. So he’s familiar with standard maintenance

Don, where in CA are you?

Fresno CA I think the closest shop 3 hours away

I used to live in Lemoore/Hanford area. A shop is a lot closer that you think. It's a short drive (approx 1.5hrs) down Rte-99. Seek out Palm Tree Rotary in Porterville. Moe, the owner, rebuilt my motor and I was VERY pleased with his customer service, recommendations, and work ethic. Feel free to drop my name. It won't get you (or me) anything extra other than making a business connection.

Oh nice thanks a lot Palm Tree Rotary is only 1 hour about from me

Glad to help and make a recommendation. Let me know how your visit to Palm Tree goes. That is, when you decide to check it out. Send my regards to Moe.

How do you guys feel about the heavy duty solenoid rack upgrade. Wondering how it does with CA emission and mpg

The heavy duty solenoids are a very good upgrade for reliability. It wont affect emissions or mpg (will actually improve if your stock solenoids are broken). They are relocated to a cooler part of the engine bay, and are a lot more durable than the stock ones too. I have a brand new set for sale including all the silicone line and viton check valves you will need to refresh the system. If you are interested, PM me. I was going to install them, but decided to go single turbo instead.

@atm0706, as a friendly reminder, please use our new marketplace if you choose to sell the solenoids. The old classified section is in the process of being closed.

Hey gen2n3 I contacted palm tree for replacement bushings and they are charging at a good price. So thanks for introducing me to them. I contacted DNA garage and their quote was high so I was like damn something else I won’t be able to fix right now. But palm tree quote was less so now I’ll be able to get that fixed sooner. First I need to tackle egr issues. I might be able to handle that without a shop. If not I’ll take it to them for that too

@Don93RX7,

That's good to hear. You should be in good hands at Palm Tree.

I understand your desire to fix the EGR without outside help. However, there is value when a shop, like Palm Tree, can diagnose and resolve an engine accessory problem. If you allow them to check out your EGR then be sure to tell him what was done to the engine, like a street port. The more information you provide for a problem will help someone else diagnose it. This thread is a good example of providing advice based upon the information you provided. Remember, when you take your car to different shops, each mechanic will not know what the other mechanic did without some evidence (via receipts or observations).

True I’m thinking of taking it there and letting them bring it back to the road legally with smog pass. But car left me broke XD now I’m waiting on my paychecks to come in to have money to get it running right. I can’t wait to start enjoying it

Don,

You should be very proud to own Mazda's halo car. The RX-7, FD in particular, is a very special car to own. However, repairs for our cars are costly! I'm glad that you were able to purchase one. It is a thousand smiles per minute when you are behind the wheel.

Based upon my experience with my FD and observing others, the further you venture from stock then the less reliable the car becomes. You could save some money here and there by doing some projects on your own. However, there are more costly projects, like an engine rebuild, that should be done by specialists.

Bottom line, welcome to the FD and may it bring you thousands of miles of happiness! Make sure you can afford the repairs that come with owning the car. That will prolong the great feeling of driving these special cars.

So gen2n3 Im taking the car to the shop to handle egr. You made a list of things to handle first. What do you mean by intake and engine coolant

Don,

Addressing the air intake refers to getting cool air into the engine. We previously talked about Adam C's cheap bastard air intake mod or you could go with other solutions. As an alternative, you could revert to the OEM configuration with the crossover duct. That would require removal of the plug from the intercooler duct then install a crossover duct. Since you are taking the car to Palm Tree, you can ask Moe. The advice he may offer would be based on how the engine is set up. Also remember, his recommendations may be based on assumptions, such as motor modifications, tune, exhaust, ECU, etc.

The engine coolant: If it were me, I would do a coolant flush, replace the thermostat, and radiator (upper & lower) hoses. You may also want to check the coolant hose (small rubber elbow) that feeds the turbo. If that is swollen, cracked, or has signs of leakage then it should be replaced. You don't want to run the turbo dry of coolant.

BTW, did you try clearing the EGR codes? Funny, last weekend, my car threw an EGR code (CEL 16). I cleared the CEL codes then ran it again - cleared the problem.

One final thought - the FD's engine management system is pre-1996. That means it doesn't have OBDII technology. You just can't hook up an OBDII scanner to the car because it lacks an OBDII port. It does have a diagnostics port but that requires a Mazda special tool. You can read certain codes, like engine, auto trans, and air bag codes by jumpering specific pins on the diagnostics port to ground. That's how it was done prior to 1996!

I bought the template from Adam. It’s being sent. Moe no longer runs palm. I guess he’s renting out the shop to Julio and it’s call gee spec. But he’s the same guy that’s been working in Palm tree guess he finally got enough to start up his own business. I’ve been talking to him. I asked if he could fix the check code issues and flush the brake clutch. And get it to pass smog. Might need him to check coolant too though. Might as well freshen everything up then maintain it after

And as far as the check engine light. I disconnected the battery then stepped on the brakes 3 times and then a long one for 30 seconds. Is that how you clear the codes? Anyway they came back on immediately once I started the car

Don,

Thanks for the updates on both your car and Palm Tree! Wow! I had no idea they changed hands. I know Julio as well but I mostly interacted with Moe. Julio is a great guy too!

You clear the codes by disconnecting the negative battery cable then pressing the brake pedal for 30 seconds. When the codes immediately re-appear then that confirms the problem is persistent and should be further examined.

I got the template and I disconnected the positive one

Don,

FYI, the FSM, Pg F-66 lists the "After Repair Procedures" for CEL codes. It states, "Cancel the memory of trouble code number by disconnecting the negative battery cable for 20 sec and depress the brake pedal. Reconnect the negative battery cable."

Try that procedure then start the car, take it for a mild drive, then check for CEL codes.

Does that help?

Palm Tree Rotary
 

Hello RX7Club,

Palm Tree Rotary is still in business and ran by Moe at the same location. Julio conducts business under a different licensed business entity named Gee Spec Automotive. He services rotary vehicles for customers of Palm Tree Rotary in addition to his business practices. Please contact us directly for further clarification.

Thank you.

Palm Tree Rotary (559) 310-9066 Moe

Gee Spec Automotive (559) 560-8534 Julio

I had an opportunity to speak with Moe at Palm Tree and he confirmed the above remarks. Furthermore, my remarks on 14 Sep inaccurately reflect any changes in ownership.

As stated before, I know both Moe and Julio. They are both great guys who provide excellent service to the rotary community! The motor Palm Tree built for me is *knock on wood* running strong since 2015! Since the rebuild, my FD has several years of auto-x and trips to Deals Gap under its belt.

Thank you, Moe for building a strong motor!

Palm Tree Rotary ***UPDATE***
 

Hello RX7Club,

I would like to clarify to the Rotary community that Julio from Gee Spec Automotive does not service vehicles for the customers of Palm Tree Rotary and has not serviced vehicles for the customers of Palm Tree Rotary since June of 2021. Please don't hesitate to contact Moe at Palm Tree Rotary for all your rotary needs.

Thank you

Palm Tree Rotary
43 N. Villa St.
Porterville, CA 93257
(559) 310-9066