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Discussion Starter #1
Hi everyone.
I took my car to inspection yesterday and it didn't pass the part where they shove a probe in the muffler. The scan results were high CO and running rich at idle and 2500 rpm.
Never had a problem before. Actually it passed inspection back in November first try no problem.
A couple of months ago the car started acting up throwing P300 code, hard starting hot, bogging down at idle, erratic idle.
Repaired somehow with:
Successful pedal dance.
New Hitachi TB.
New generic crank + cam position sensors.
New generic MAF
New upstream O2 sensor. Not the same number as the OEM but the NTK dealer claimed it was their version of it.
New Bosch fuel pump. Had to wire in the fuel temp sensor from the old pump.
Removed the 2J CAI and replaced with the AEM short ram and stock MAF housing because it's raining a lot and the roads flood.
Cleaned injectors.
Cleaned coil contacts. Solid spark.
I can't find any vacumn leaks.
Here is the situation.
I am located in a third world shithole country. I can't get parts shipped here because of retarded import tax. Finding spare parts down here is impossible at best.
I need this car for work. I really like this car. Pulls hard, safe, comfortable and looks good.
73000 miles. Owned since 07. Bought it with 37000 miles.
Current status:
CEL OFF
23 MPG
Slight delay start hot.
Fires right up cold.
My plan now is:
1) Scan for codes.
2) Reset LTFT doing the MAF unplug.
3) Reinstall OEM MAF and upstream O2 sensor.
4) Weld on a new CAT.
5) Reinstall CAI.
6) Inspect for vacumn leaks.
7) Inspect for exhaust leaks before O2 sensor.
Any and all suggestions are greatly and immensely appreciated always and especially during these extenuating circumstances. I used to get parts from friends and family members traveling to and from USA but now for obvious reasons that's not happening.
 
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I either missed it but I didn't see spark plugs replaced, that could fix the 0300 and the rich idle right of the back.
 

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Discussion Starter #3
Yeah sorry for the long a** post. Sparks were replaced. p300 is gone. Now it's running too rich. How do I lean it out without a tune? Thanks
 
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Rest the fuel trims when it's hot and go straight into tb and maf relearns after clearing all the codes, let it relearn as long as you want.
 

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I did what you said. Also changed back to the old OEM o2 and lowered the idle to 700. Idle is smooth and stable. I drove it to work this morning. About 20 minutes ten miles mixed HW and dense urban core driving. The MPG display started out blank then went all the way up to 29mpg. It had 23mpg max before reset. Now I have to get an emissions measurement and see how that goes. My friend suggested buy a new cat but I am trying to avoid it if I can.
 
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I did what you said. Also changed back to the old OEM o2 and lowered the idle to 700. Idle is smooth and stable. I drove it to work this morning. About 20 minutes ten miles mixed HW and dense urban core driving. The MPG display started out blank then went all the way up to 29mpg. It had 23mpg max before reset. Now I have to get an emissions measurement and see how that goes. My friend suggested buy a new cat but I am trying to avoid it if I can.
I suggest you follow your friend advice your car is due for replacement because sooner or later the car is still gonna give you a more problem.

Sent from my Nokia 2.1 using Tapatalk
 

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This might sound dumb, but drive ur car on the fwy for 200 miles. Make sure you are running 91 octane. And possibly check if the ecu has been altered. Open up the hardness and check if theres a sticker on it.
These cars run rich from factory, so it could be testing error. But from the sounds of it, it sounds normal
 

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I suggest you follow your friend advice your car is due for replacement because sooner or later the car is still gonna give you a more problem.

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His friend said CAT, not car. These cars are reliable asf. Ive used and abused mine and it won't die. That could be too, a new CAT. Where do you live, its hard to have worst emission laws than California.. soon to be Nevada ( they are adopting California emissions)
 

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Discussion Starter #9
Yo dawgz I'z sitting here in my car it's midnight. No bad not driving. From beyond south a da border. Inspection tomorrow six am. Wish me luck. MPG 22.3. I can't load the anticomunnist logo as my profile.
 

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Discussion Starter #10
What up everyone. Failed again this morning. I took it to a shop to get tested and their machine result was good af. Official testing station claims not passing. It passed the idle test barely. It failed the 2500 rpm test for too much CO. I think the official testing station is rigged forcing drivers to buy new cars a lot. This car just passed inspection in November last year. It used to pass no problem even without CATs. Never driven hard. Always maintained. I just can't believe it turned into such a pos all of a sudden. Getting 20 mpg now. Still no CEL. I'm going to try it again with a new CAT $180 and if that doesn't work then a new O2 sensor another $180 from the dealer. Don't want to keep throwing money at a $1000 car. These cars are too unaffordable. The electric system is stupid sensitive with sensor parameters so tight. My friend's 95 civic gets like double the mileage. Doesn't give af about it. Drives it like a bat outta hell, whole transmissions are like $40 and passes inspection every year first try. I thought he was joking when he said straight up trade but now I believe I was the one that missed out on the deal of the century. Was offered $400 for my car just the other day. Fire sell it and ride my broke @** on the bus to work or bicycle.
 

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I thibk it could be the tester wants money to pass you. I cant help it think what place is worse than California emissions, soon to follow Nevada (they are adopting California emissions). Maybe if you seafoam it it could pass. I seafoamed my spec years ago. It worked out well. Btw 20 mpg city is decent. I get 16 to 19 but i am 2jr reflashed.
 

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Um yeah 20 mpg is too low and its dumping fuel for some reason. High CO usually is a consequent of too much fuel or not enough air. Sometimes things happen where no cel is present. I would do a serious quality seafoam cleaning. What is actual fuel pressure? Take a look at the gunk around the throttle body plate. Use good spark plugs. Clean MAF with MAF cleaner, not brake clean. These things do happen. I would think all of other things would throw some kind of code. Do you have access to a scanner?
 

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Discussion Starter #14
Thank you for your help everyone. Feeling a lot better about the car today. Threw a new CAT on yesterday and the emissions test at the muffler shop came out great. I have a generic plug in code reader. I also have the bluetooth dongle with car gauge pro and torque apps on the phone. Maybe I can find a way to measure fuel pressure. New inspection on Friday. I used to use 20w50 before I knew any better and the chain rattled like crazy. Now I put in 10w30 and the chain's quiet but you could be right it could've gotten stretched tf out. New TB, new spark plugs the ones it says in the manual. New generic MAF. As far as I can see the intake is not obstructed. And IICBH I wish I could pay off the emissions officer but they're surrounded by like a thousand cameras everywhere, every movement monitored and surveilled. Someone else suggested bad coolant temp probe.
 

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Coolant temp sensors on modern cars uaually throw codes. Yeah Emissions is a bitch, State police do watch and record all encounters, and even send dummy cars to shops to make sure they fail.

I dont think this car has a pressure sensor for fuel, you would have to use a mechanical gauge. But if a cat solved the issue, then boom.
 
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