Im over it.
 

The long struggle with getting this motor to run right. Go right ahead and flame away if u must, and tell me to stop driving the car in its condition. I drive it once in a blue moon to keep things fresh and the battery charged, but I'd love to be able to take it out on a 15 minute drive without having to keep the motor from stalling, or at least be able to enjoy giving it gas for once in its life. Im honestly sick and tired of trying to figure out whats wrong with the motor. Some of the people on this forum know my situation already, but if you dont:
rebuilt streetport with less than 2k miles.
stock turbos rebuilt 500 mi before blown motor, and a pwr radiator and aluminum AST.
Catback, stock pre cat, and drop in filter. stock ECU, which is probably the problem, or its the DP but I cant possibly imagine that even a new ECU will fix this. keep in mind that my motor is still new, and I DO go very easy on it. I have never floored it, except when trying to keep it from stalling out. I boosted only for short periods to see if the turbos were in fact working properly.

bad symptoms:
absolutely no power, full boost and 10-8-10 pattern.
cold starts has a really rough idle, stalls out a lot on its own if I dont give it gas.
when warm, idle is high, turning the wheel a bit at a stoplight or something can make it go below 1k very easily, and it just stalls out. Putting it in first gear renders the same results. I have to get on the gas before I put it in gear to keep it from stalling out every now and then when its warm, or when its cold.
oil leak, dont know from where, but it seems like the oil pan gasket.
exhaust glows red, as does the turbos after a long run. Lots of gas smell at start (cold) up, and extremely hot when warmed up. Can a clogged DP be causing all of these problems??? I can't possibly think of what else it could be mechanically.

Stock ECU doesnt go well with a ported engine. I think timing needs to be altered - that may be the reason for your low power.

Other symptoms are pretty much standard stuff on FD ;)

Oh, and if your DP would be clogged you couldnt be getting a perfect boost pattern.

Ignition timing ;)

It's not your ECU.

I wouldn't think you would get a 10-8-10 pattern if the DP were clogged.

Maybe a fuel injector problem? Do you know if it's running rich or lean?

I don't understand how you can get a 10-8-10 pattern and have no power.

Why cant it be the ECU ? Ignition maps are in there and for a ported engine stock ignition maps dont do well.

he could get 8-10-8 and be running no timing and very rich... that would make no power.

I say get an afr meter on the car and see what thats doing... try upping your idle a little bit with your idle adjustment screw. If all else fails go haltech :) oh wait you said you want a better idle, nm go PFC :D

I don't see how a stock ECU on a streetport would cause a bad idle and stalling, when others have reported the stock ECU working fine (although not safely).

I recommend getting rid of the stock downpipe regardless of it being a culprit or not.

paw I have heard this as well, which is why its so strange to me that the car runs like it does with a perfect boost pattern, and no power, associated with all those symptoms.

Come to think of it, I had a fuel injector(s) that was/were stuck open, so I replaced both of the primaries, and sprayed the secondaries with carb cleaner. This seemed to help immensely, although it still has problems. Could another one of the injectors still be stuck? And if its running hot, doesnt that mean its lean?

Stevey,

If you want to drive the car up here to the SF area, I'd be more than willing to help you with your car.

You've got to have patience and realize that there is a light at the end of the tunnel.

There are plenty of us who have completely working fun and very fast cars - it is not a myth. It would be misfortunate for you to just throw in the towel without ever experiencing what it was supposed to be like.

I got to feel a bone stock one when I first got it, and fell in love with that feeling...from there it went downhill. I have been putting so much money into this car with absolutely no rewards from its performance, nor its reliability. Just wish there was someone around here in San Diego who could take a look over my motor and just take better guesses than I have been able to make about what is wrong with the motor.

I would replace pre-cat with a down pipe, and find someone with a Power FC in your area, and see if thats the problem. You mean to tell us that there are no Rotary shops in San Diego? Shit we have 4 in Dallas/Fort Worth.

A large streetport would more then likely run like crap on a stock ecu. Defiantly get a downpipe. Does it smoke at all?

I was under the impression from some reading a while back that a ported motor will run like absolute ass on stock ECU and stock fuel system. There was someone a while back who posted they did something similar and had nothing but problems.

have you done a compression check since the rebuild?

1st, get a dp for god sakes (gees, this should be one of the first mods rightnext to the ast tank. you have 370 post so you shouldnt still be a newbi, i mean where the f are you posting, dont tell me your at the lounge only!)

2ndly, unplug all the stuff that controls idle to check if its not something more serious that needs attention such as the...

ISC
AWS
Wax rod assembly
fast idle screw
airpump solenoid


3rd, compression check the rebuild, lots of people get craptastic engines after the rebuild cuz the people putting it together dont know what the hell they are doing. just because someone rebuild it does not mean its a good engine, hell it could be worst then when you got it rebuilt for all you know.

4th, get on a wideband/dyno to do some tuning

When I got my engine rebuilt with a street port I was warned that it would idle like crap without an aftermarket ECU.

Just depends on how much $$ you want to cough up. I know you could drive to ORange county and go to a number of Rotary shops up here including a licensed Power FC tuner. If your tired of putting $$ into it then sell it because you need to realize that by doing certain modifications other modifications need to be done to support it. You have a good start but still see a 2K money pit or so ahead of you if you really want to get this thing working to its best ability with the mods already done. If you need info on any reliable FD shops in orange county feel free to PM me.

skunks, I dont know where any of those things that you listed are, let alone what they are. Im making the assumption that ISC is Idle Sensor Control, the wax rod is related to the dashpot? and the idle control sensor screw is self explanatory. But what should I look for more importantly in each of these?

Sorry, I gotta start learning this stuff somewhere, and I come here to get my fill on the various acronyms and info, then sorrily stick my head under the hood just ponder.

www.iluvmyrx7.com go there and d/l the service manuals.

heres what each one does:
Here's my list of items affecting idle rpm. Notice that the AWS (#6) operation is binary; either its open or closed. Where as the Fast Idle Cam (#3) can have an infinite range of positions. Therefore, (and ignorying the PITA AWS) as your engine warms up the idle RPM SHOULD gradually decrease until it reaches its normal hot idle speed.





Throttle plate stops - Physical limit. Setting generally made only during production to determines the absolute minimum closure point of each throttle plate and thereby prevent long-term wear that might cause increased air leakage.

Air bypass adjustment screw - Physical adjustment. About a 3/8 inch diameter slotted brass screw whose head is visible on the throttle body below elbow mounting area and slightly toward the firewall. Manual setting that controls how much air bypasses primary throttle plate and used to set the fully-warmed-up idle RPM.

Thermal wax/fast idle cam - Thermal range. Intended to increase idle speed based on the relative temperature of the throttle body. Has two adjustments, one for matching cam position to an actual temperature, and the second for setting the amount of RPM increase at that temperature. Heated by flow of engine coolant and should completely loose any effect following warm-up.

Deceleration dashpot - Slows rate of throttle closing. Designed to slow the rate at which the primary throttle plate closes the last few degrees, but should not result in more than a 1-2 second delay in full closure. Adjustable but rarely needed following correct installation.

Idle air control valve - Closed loop controlled by ECU. Responsible for adjusting idle RPM to offset electrical loads (see below) and A/C compressor. It also feeds in air during engine deceleration to prevent afterburn.

Automatic Warm-up Solenoid - Binary Thermal. ECU controlled valve that provides a simple open/closed operation. When open passes a fixed amount of additional air around throttle plates during initial cold start conditions that are generally thought to last only 5-10 seconds. Effect is bypassed on cars with manual transmissions by placing transmission in any gear before starting engine.

Electrical Load Control System - Electrical load. Monitors several electrical circuits and if one or more shows active, the RPM is increased by the IACV (see above). Thought to have no throttling action; just normal and high, but this has not been fully verified. Does it increment in steps with multiple electrical loads?

Vacuum leak(s) - Uncontrolled amount of air. Any uncontrolled source of air leakage can affect both idle speed and idle A/F mixture. In general they cause the idle speed to float up & down over several hundred RPM. Small leaks tend to slightly increase idle speed for 5-10 seconds followed by a stumble, while larger leaks make the idle speed lower than normal and very unstable. Effects can vary greatly depending on the amount of air leakage, engine condition, and state of tune.

:) good luck! I just took out EVERYTHING xcept the screw and j/ deal with the low cold idle and check engine light.

-Zach

low idle usually sometimes means low compression. i would get a compression check if i were you. even though the motor has just been rebuilt, it could still be a compression problem. a ported motor almost requires an aftermarket ecu. that may fix some of your idle problem, but ported motors generally always have a rough idle. definatly get a dp asap. excellent relibility mod, and it removes more heat from the engine bay.

Steve,
I PM'd ya. Also check out sdrx7club_discuss@yahoogroups.com

CHECK YOUR IGNITION PICKUPS, IF THERE IS ANY PROBLEM WITH THIER ALIGNMENT THEN YOUR ENGINE WILL CRAP OUT

I had this same problem on an old rx3 carby 12A! It would use heaps of fuel, heat the exhaust till it was bright red and have bugger all power. I was down to 20km/h up some fairly small hill revving the crap out of it. After heaps of stuffing around it turned out to be the rotor button in the dizzy, a $10 fix!!!!

I know you don't have a rotor button but maybe the leading plugs are not firing or way out of time. Have you tried a mazda dealer?

My thoughts exactly...

JUNK the BITCH!!! whats CHEAPER?
HEADACHE or ASPRIN?

Who ported/rebuilt the engine? How big of a port does the engine have? I know that a stock ecu can comfortably idle some ported engines, as I ported my intake ports when I rebuilt my engine, while leaving my exhaust stock. I put the stock ecu in the other day when troublshooting some problems I was having with the AEM, and it idles just fine.
I agree that you should check the engine's compression, just for good measure. Also, check to see that your injector plugs are securely on the injectors. Make sure to check the routing of the spark plug wires as well. And if you know anyone in the area who has a PFC that you could put in your car for a few minutes, then put it in, and go to the sensor check screen. If anything is off, then you know to check it. And for the love of God, get that damned precat out of the car.

My car idle fine (street port, 3"dp, and stock ECU)
but it did smell like there was a fuel leak somewhere but I looked but couldn't fine it.. and then I installed a PFC and the fuel smell stopped.. I am assuming that it was running super rich..

Flipn

Is the O2 sensor hooked up and is it good?

Also, what about all the grounds all over the engine? Have you checked to make sure they are good?

STEPHEN

yeah, goofy should know. he's had a lot of both in these years w/ his rx7's and the customers in his shop. :rlaugh:

Sorry if you did this already, but make sure the plug wires from the center coil go to the plugs that are closest to the ground, and that the coils to the left and right go to the plugs that are closest to the sky.

-Max

This thread is pretty old. Steves car runs fine now i believe. I saw him last week, looks all good.

What was the verdict??

I never understand why people make up threads asking for questions to never follow up on how they fixed the problems.

UPDATE people!!! Inquiring minds want to know. Oh shit, did I just show my age???

check vac line that goes to the stock boost sensor...mine came off and the car had a rough idol

I have run 2 of my fds with streetports on stock ecu. One was a mild port the other pretty aggressive(what I was told by previous owner) I have never run into a problem with a port and stock ecu. One of the cars has intake,dpipe,catback,and streetport with the restrictor pills pulled so the car only hits 8lbs of boost the other with the large streetport has just a downpipe and they both run great. I have a hard time believing it is the ecu. However it never hurts to check.

Edit: I am an idiot. I didnt realize the problem is already solved. Oh well.

He plug in the Power FC and all his problems went away.

ok, so sorry for not "updating"...I figured that this thread would never get dug up for some reason, and if it did, other posts on my progress with problems would help tell people that my car is now running well. Anyhow, I have solved all the problems that my car has, and I think it was due to the ECU. I had XS engineering put a Power FC in, and tune it for reliability, to just get everything running properly. I could potentially squeeze a lot more power out of my port and current setup, but if I'm going to be driving this thing everyday, and want to get on it a little bit, I want to take the best possible route that I can towards extending motor life rather than risking possibly running lean, or overheating for any reasons.

The cooling fans are now turning on for some reason, idle issues are fixed, no more hesitation at 3k, boost is clean, 10 lbs. all the way through, sometimes up in the 12 lb. range if I really get on it. The only problem that seems to still be a bit of a hassle is the start up at mid to cool temperatures. If I drive my car for say, 20 minutes, turn it off then come back to it when its on its way towards cooling off completely but not entirely stone cold, (i.e. stock temp gauge sits low, but not all the way down) starting the motor is tricky. The car pulls the idle up like it would if it was cold, then kills it if I don't stay on the gas. This occurs only momentarily however, as once I keep the RPM's up and keep it moving at a parking lot speed, this problem vanishes within 5 seconds of driving. No biggie so far.

I thought it was so many other things, but it just turns out that I needed a computer to fix it. Its interesting to me that some people have been able to run the stock ECU with no problems on a port. This makes me question other problems that the car is having outside of the ECU, and whether the Power FC compensates for these issues, whether mechanical or electrical. I would love to hear other suggestions if you think my situation can be further improved.

Thanks for filling in for me saburo, I know u know how my car is running...u've seen it in all its living color.

Glad that you fixed your problems, so congrats! and thank you for the update :)

i would re-ground everything under the hood.