C24Creed

Ok,so after spending 700 into the car to replace all spark and timing and some other stuffs,my car ran beautifully. I decided to give it a nice little cold air intake, and today (after 3 days of running perfect woth CAI) I got a check engine for those codes.

I was told just to change the oxygen sensor in front of engine, but I want to hear some other opinion on my info:

The car seems to rev a lot higher than normal. It shifts around 4000rpms and 1st gear sometimes takes it to 20, 2nd to 40,and rest of gears happen fast.

Also, the car made a popping sound a bit before the check engine came on.It wasnt loud,but sounded like air (filter?). The car exhaust then sounded low and loud (if that makes sense) when accelerating,but performance did not change.

I wanted to know why the o2 sensor would randomly give out after CAI, and if there are any ideas than it being a bad sensor. Having more fun haha, thanks!

ezone

Check fuel pressure first.
Got data list? Does the front O2 sensor read as lean most of the time? Where are fuel trim numbers? Positive 20% or more?

C24Creed

I will look up how to do all that and respond tomorrow. I dont have any data,I asked my mechanic if he could run his tablet diagnostics for me. The code said rich. Im guessing his data will give fuel trim as well.

If its not the sensor, which I dont think it is because I reset ecu and drove another 50 miles to the beach no issue, how would I go about fixing these fuel pressure, data,trims etc?

Wankenstein

If it ain't broke..don't install a CAI.
No power gains from a CAI on the stock engine.

C24Creed

I initially did it because the stock had a slice near the intake temp sensor. I thought the random lack of power was from the slice, when it was just tps from earlier thread.

ezone

P0171 is LEAN, not rich

P0170 shouldn't be there, your code read might be lying. Recheck on a couple different scanners?

Got freeze frame data? That can be quite helpful info.

You don't fix data and trims, you read them..... those are data I would be looking at as telltales..... if you know how to interpret the data it's invaluable. If those confirm a lean or perceived lean condition, then we have a direction to go with troubleshooting.....namely checking things that would make an engine run lean. You also need to know the driving conditions it set the code in, and that's what the freeze data is for.

C24Creed

Ok,will do my best to find that data, thanks!

C24Creed

Apologies for leaving for awhile on this thread. I wanted to update the situation:

Codes went away on its own the day after and never came back.The revving is normal. The idle is a bit off, when it sits too long it sometimes tries to drop to 0,but jumps itself back up. This happens every 30 seconds or so at idle, with or without the A/C.

Car still has same issue. When its cold, first 5 minutes of driving it loses responsiveness to throttle. Sometimes, a popping sound occurs during this time, sounds like a backfire. Eventually, the car becomes more responsive,however it doesnt accelerate perfectly normal until I turn the car off and on. During this condition, when I accelerate, the exhaust(or engine?) sounds loud but low, compared to the higher pitched sound it usually makes during acceleration.

If I turn the car off and back on under operating temp, it runs fine and does not encounter this issue.

This issue seems to only happen when its cold operating temp. Also, I could not find anyone that could acquire data for me, whom have tried to charge 100$ which I will not pay. Id rather spend 100$ on an o2 sensor,another iacv, carb cleaner,fuel filter, etc. My usual mechanic is out of state until November,who would only charge me 20$.

Is there any suggestion without data?

ezone

When it runs bad, how long does that last? 10 seconds? 3 minutes?

C24Creed

There are two stages of bad performance:

1st, it loses throttle responsiveness, and thats for about 10 seconds.

2nd, throttle begins to respond and it just has an overall sluggish performance. This lasts until I turn the car off and on again. By sluggish,I mean it accelerates slow,makes a loudlow noise when I floor it, and wont go past 80-85mph.

ezone

For this one, unplug the primary O2 sensor (front sensor) and disconnect the battery for 15 minutes to clear out learned fuel trim tables.

Reconnect battery and drive it, see if leaving that sensor unplugged gets rid of that complaint.


This complaint goes away if you flip the key off and on again? Weird. I'd want to experience it myself and take some scanner readings..... it doesn't sound familiar to me right now (unless the O2 sensor is causing it, you'll find out if this symptom goes away while the sensor is unplugged).

If you had a scanner or scanner app you could gather some important operating data for yourself.


You know that's breaking the law just about everywhere in the US, right?

C24Creed

I will try that solution for part 1.

Yes,I also couldnt find anyone else who had that sort of problem for part 2,but it only happened after the loss of throttle so sensors sound pretty viable of a fix.

75mph speed limit with fast lane and flow of traffic permits upwards of 85.I have a clean history and have even driven around cops on our highways at such speed. Thankfully it may be above the limit but as long as Im not purposely flooring it or weaving (which Im not that type of driver),its not as bad an issue as it seems. I mostly identified this however for the vehicle performance issue,its not that I always go out of my way to speed.

Hooefully that o2 sensor process works,Ill letya know asap!

ezone

I was giving you static----- because I'm an upstanding 100% law abiding model citizen. A pillar of the community.



I'm in a 70 MPH state but a lot of traffic moves at 80..... and 85+ depending on the area.... and I usually try to stay in the middle of the fastest pack I can find.

and I have made posts on here bitching about the horrible gas mileage I get when I go that fast LOL