What do y'all think it could be?

Messages
379
Location
Ohio
2007 Honda CR-V, automatic, 230,xxx miles.

It's been having issues with throwing lean codes left and right for a year or so now but lately it's gotten real bad. The check engine light has been on consistently for a week now.

When idling my car the RPMs will slowly fall until it sounds like it's going to stall out then it "catches" itself and the RPMs go back up for awhile until it does it again.

My MPG lately even with lots of highway driving has been averaging 16.5 to 17 and I usually get about 25.

My car used to burn almost an entire quart of oil every thousand miles but since I've switched it to 10w30 I only burn about 1/2 to 3/4 quart during the entire OCI.

I did have a vacuum leak that was bad enough that my car would stall out in gear coming to a stop or taking a turn slowly but that's been fixed over a year ago.

I've already had the intake decarbonized, I've installed a new maf sensor and air filter, verified the O2 sensors are good and that there's no exhaust leaks.

Before I pay for a diagnostic could anybody give me a guess on what may be going on now?
 
Messages
2,235
Location
Muncie, Indiana
I guess in all the stuff you did you didn't check the fuel pump or the injectors, it's possible that you have a failing pump or the screen/filter to the pump is clogged or your injectors are plugged.
 

cwilliamsws6

Thread starter
Messages
379
Location
Ohio
I'm gonna guess that the cat may be toast.
Wouldn't doubt it with how much oil I used to burn before.

I guess in all the stuff you did you didn't check the fuel pump or the injectors, it's possible that you have a failing pump or the screen/filter to the pump is clogged or your injectors are plugged.
I have an elm327 adapter and the paid version of the torque app, and I can view all of the sensor data from my car. I could see if I can monitor my fuel pressure maybe.

Sounds like you still have a vacuum leak.
Since that's the easiest thing to check for because you just have to blow the smoke into the engine bay and watch for it to go somewhere I'll do that tomorrow at work.
 
Messages
3,413
Location
USA
If the fuel trims look OK at cruise but go way lean at idle, it's very likely an air leak.

Though I see low highway mpg as one of the complaints and an air leak wouldn't do that.
 
Last edited:
Messages
12,517
Location
OH
Yes, oem pcv valve.

Fuel pressure regulator is common on these to go out. Plus it affects the rpms and lean codes are generated. Experienced this on an older 4cyl Accord with higher miles. There’s a tsb on it so kind of common.
 
Messages
9,154
Location
Marshfield , MA
The way to diagnose is to remove the vacuum line to fuel pressure regulator. If gas drips out it is bad. Also, this would explain 2 things. the low MPG and the seemingly better oil level. Sniff the dipstick , if it smells gassy,, looks black, and flows easily. Change it, maybe change it just 'cuz. Please post your results
 
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