P0171: System too lean
#26
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Location: Brunei: Where Ricers show off their fugly rides
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Originally Posted by Hymee
So do you have a mate with an RX-8 you can try swapping the MAF sensor with? Simple to do - undo 2 screws and a connector. If that fixes it then you can order one from spare parts. Don't forget when it is all fixed, you might have to reset the CEL (or you didn't get one?? - weird) using your sCANalyser.
I remember that the 1st time i'm doing deflooding, i don't see any oil/fuel drains from the sparkplug holes (front rotor), even the plugs (trailing & leading) are clean (no oil).
By common sense, no fuel injected to the rotor (could be fuel-cut by ECU) won't fire up the engine. Give me some light please. I'm a newbie LOL. I remember there's a link that shows how rotary engine works.
#27
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Originally Posted by tems900
can buy e MAF in S'pore for SG$252 include tax, just replace it today. Have driven the car for 2yrs , 37000Km, having problem starting e car since 3 weeks ago but no CEL, had tried all the deflooding procedure, change battery, new spark plug, put back e OEM CAT midpipe, now MAF & i hope it work, if not i need to remove the Trust CAI & put back e OEM airbox, if all e change still don't help, i need to sent my ECU back to KnightSport for retune. ![Mad](https://www.rx8club.com/images/smilies/mad.gif)
![Mad](https://www.rx8club.com/images/smilies/mad.gif)
#28
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Originally Posted by KJ238
He's gonna do that today... He practically knows every rx-8 in this country.....
I just hope that it is as simple as a MAF problem.... Good luck bro
I just hope that it is as simple as a MAF problem.... Good luck bro
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xDIESELxFOXx (05-06-2021)
#30
Rough idle, jerky acceleration and very slow take off
Hi I own an 04 auto rx8 with 115xxx miles. Every thing is pretty much stock, I have changed the coils, plugs, and wires. Replaced the fuel pump and new starter and checked the compression and it hits 120-150 psi. My problem is the car idles pretty rough and stalls at idle and whenever i put it in gear. Also whenever it doesn't stall out, the car is really rough while in gear like the car rpms drop and the ecu i guess tries to keep it from stalling and has the needle jumping up and down and has my car shaking and jumping. When i press the gas down it doesn't accelerate normal i have to press and fiddle with the gas peddle constantly for it to actually raise the rpms up and semi drivable but as soon as I hit the brakes while driving like a stop sign or light, it does the same thing and i have to repeat fiddling with the gas in order to raise the rpms up to speed. The car is just sluggish and rough. I have a solid cel light and the codes were P0743, P0171, and P0506. I need help trying to figure out what the problem is. I have cleaned the MAF sensor and have new coils installed and checked my plugs and they were still pretty new. Only thing I haven't checked is my cat converter. It doesn't show any signs of it going bad like glowing red or anything so i'm going to check if its clogged but besides that I have no clue what else it can be. Please someone help.
#31
FULLY SEMI AUTOMATIC
iTrader: (9)
check the cat, clean ess, 20 brake stomp
way to bring this thread back from the dead. im sure when the mods wake up they will delete some of your multiple posts
way to bring this thread back from the dead. im sure when the mods wake up they will delete some of your multiple posts
#32
I will let you know what I find with my set up. I have been trouble shooting a new car to me that I purchased for a really low price.
I have P0171 as well as a few other codes, misfire, another lean code, and rpm too low code.
Mine only occurs when the car is warming up, runs great when the O2 sensor kicks in a few minutes after the car has been started. hot and cold starts well and idles well. Since the car is new to me its tough to know what this car feels like in upper rpms but it feels slow up top. brand new coils and spark plugs, clean air filter, new MAF sensor which took care of a lot of other codes the car had, I also did all that other stuff (like a bad SSV solenoid).
I took out the fuel injectors and had them flow tested and they are currently being cleaned. That code happens when the injectors need to correct over 20%, so the injectors must be bad in my mind. so I got pics of my injectors and all of them are partially plugged. every single one. They are rebuilding them and I will let you know if that was the problem for these codes. I also had junk around the throttle body which I cleaned up as well.
will report findings hopefully at the end of this week.
I have P0171 as well as a few other codes, misfire, another lean code, and rpm too low code.
Mine only occurs when the car is warming up, runs great when the O2 sensor kicks in a few minutes after the car has been started. hot and cold starts well and idles well. Since the car is new to me its tough to know what this car feels like in upper rpms but it feels slow up top. brand new coils and spark plugs, clean air filter, new MAF sensor which took care of a lot of other codes the car had, I also did all that other stuff (like a bad SSV solenoid).
I took out the fuel injectors and had them flow tested and they are currently being cleaned. That code happens when the injectors need to correct over 20%, so the injectors must be bad in my mind. so I got pics of my injectors and all of them are partially plugged. every single one. They are rebuilding them and I will let you know if that was the problem for these codes. I also had junk around the throttle body which I cleaned up as well.
will report findings hopefully at the end of this week.
#33
SARX Legend
iTrader: (46)
i just solved this code for a local guy on Sunday after he took it to the dealer and Midas. They could not find anything because they are incompetent lazy *****. He had oil in his intake (full quart too much oil in the engine) and a major vacuum leak at the jet air hose on the lower intake manifold.
Don't guess, diagnose.
Don't guess, diagnose.
#36
Yes, the flow tested the injectors, rebuild/clean them, and reflow test.
The first flow test all of them failed. They rebuild/clean and on the second pass 3 injectors failed.
The car runs poor from a cold start, then runs great at idle after 3-5 minutes of warm up. The car threw a bunch of codes before so I fixed a lot of them, one including the SSV but the car still felt low on power up top, and a little sluggish. After some thought I figured I would get them flow tested and possibly rebuilt due to the issues and running low on ideas of what it could be.
I am hoping this solves all the engine issues. I still need to clean connections on the ABS lines and put dielectric grease on them. Just knocking these out one by one as issues arise.
I still might have a bad ESS sensor as just about everything on this car has needed replacement. I am doubtful that it is bad though.
#39
Just to have it be clear. the injectors didn't fail open or closed or anything like that. The spray pattern was horrific on the first flow test and both low and high pressure. They were cleaned and 3 of them still had poor spray patterns although the spray patterns were much better than the initial flow test.
I should be getting the little O-rings from Mazdatrix for the 3 injectors to have all new gaskets when I reinstall everything. Hopefully I should have an answer here shortly if it worked for my problems.
I purchased 3 new injectors from fiveomotorsports, pretty good prices for denso injectors new.
I should be getting the little O-rings from Mazdatrix for the 3 injectors to have all new gaskets when I reinstall everything. Hopefully I should have an answer here shortly if it worked for my problems.
I purchased 3 new injectors from fiveomotorsports, pretty good prices for denso injectors new.
#40
I put the car back together and it looks like it solved all the issues.
I still have a really rich idle on cold start up but all the other codes on the car are gone. no check engine lights for a few drive cycles. hopefully it continues. Perhaps being at 6,700ft above sea level and it being open loop will just have the car run rich on warm up.
the car drives a lot better and has a lot more power as well.
I still have a really rich idle on cold start up but all the other codes on the car are gone. no check engine lights for a few drive cycles. hopefully it continues. Perhaps being at 6,700ft above sea level and it being open loop will just have the car run rich on warm up.
the car drives a lot better and has a lot more power as well.
#41
I put the car back together and it looks like it solved all the issues.
I still have a really rich idle on cold start up but all the other codes on the car are gone. no check engine lights for a few drive cycles. hopefully it continues. Perhaps being at 6,700ft above sea level and it being open loop will just have the car run rich on warm up.
the car drives a lot better and has a lot more power as well.
I still have a really rich idle on cold start up but all the other codes on the car are gone. no check engine lights for a few drive cycles. hopefully it continues. Perhaps being at 6,700ft above sea level and it being open loop will just have the car run rich on warm up.
the car drives a lot better and has a lot more power as well.
#42
The car actually learns the idle, and as soon as you turn your key to crank the engine, it adopts the Long Term Fuel Trim to start with. Disconnect your battery for 10 minutes and reconnect it. Start the engine, and see how rough the idle really is. This resets the ECU, aswell as the Long Term Fuel Trim. If the issue comes back, then you might have a vacuum leak, incorrect MAF values or a faulty o2 sensor. I'm still figuring it out myself, as I have the same rich idle problem.
I already did the ecu reset, had the battery disconnected when I did the fuel injectors.
I think the car just runs rich when its cold. the coolant sensor is reading great and acts normal, the MAF sensor is brand new and the car runs GREAT when warm. It could be the O2 sensor as the car has 129K on it and has seen some coolant from a coolant leak in the engine which I fixed. so I am replacing that as well, so we will see. The car is not throwing any codes anymore but perhaps the O2 sensor is lazy or damaged and I got a super good deal on a denso sensor new so I couldn't pass it up.
#43
electronics cleaner will eat away at the sensor. They make MAF cleaner because all the other cleaners have chemicals that are not good for it.
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