My honda CR-V is throwing code P0172 (running rich). What can be the cause of this problem? Seems to idle a little rough upon startup, and looked like the RPMs were bouncing a bit when I was driving in rush hour yesterday. The light turns off once in awhile and will pop back on. I would love to get this fixed, any help would be great. Thanks.
Without looking at it, it will be quite difficult to diagnose. One thing off the top of my head that would/could be a common cause for such symptoms would be a dying or dead ECT sensor. A simple way to check that would be with a scan tool and see what the temp the ecu is seeing. Also, you mentioned the rpms were bouncing (as in you were cruising at say 2500rpm then the tach started jumping up and down???) If so, 9 out of 10 times that means your distributor is on its way out. If that’s the case, you may receive a too rich code due to a misfire/multiple misfires.
If you have problems diagnosing/fixing, call Swerve at 685-8600 and set up an appointment. Hourly rate is low, and I know Hondas quite well and shouldn’t have a problem diagnosing/fixing unless it’s an intermittent electrical problem.
I am going to change the plugs and wires today and see where that takes me. The distributor cap and rotor may also be causing the problem, like you said. The RPMs were bouncing pretty much how you described, but it only did it a couple times. Idles a little rough, as well. It doesn’t seem like its anything too serious.
Hopefully not your issue, but refer to honda TSB 03-038
I’m hoping that is not my issue. The car already has 195,000 miles on it, and its not running horribly. RPMs only bounced like that the one time. The sparks plugs and wires were smoked, I just replaced those yesterday. It seems that has helped a bit, next I will do the cap and rotor. I am thinking that it just needed a tune up…hopefully.
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Also, it seems the code that was showing up for the issue you mentioned was P301…so hopefully that helps my cause.
cap and rotor might not be enough. A dying ignitor in the distributor is often the culprit, even with most intermittant issues. The ignitors in honda dizzys tend to take a crap frequently, and it just so happens that’s the most expensive part in the dizzy to replace. So I’ll typically replace the entire unit. OEM honda or Richporter is pretty much the only replacements I’ll run too, because most others I’ve tried have died months after replacing.
Thanks for the info. I am hoping that it is not the ignitor, the car starts up fine though. The only issue is the car just seems to idle a little funny. How much does an ignitor normally run?
i want say somewhere between $90-110.