Honda civic 98 P0170, P0171
 

Hi,
I have a 1998 ex automatic. I recently replaced my valve covergasket and Distributor O ring. My car was previously running a knock sensor code p0325(ONLY). I replaced the knock sensor and now a new code is up, p0170 and p0171. Also when I shift from 2nd to 3rd gear, my rps spikes up and seems like it has trouble shifting from 2nd to 3rd.( it lags behind a bit). I was wondering if any1 has any ideas on how to fix this problem or what I should target. My mechanic suggested replacing o2 sensor first, so I am waiting on that.

Re: Honda civic 98 P0170, P0171
 

P0170 isn't on the code list for that car, as far as I can see here.

P0171 is a lean code. Got freeze frame data?
If the FF data shows the code set during driving, look for a fuel delivery problem.
If the FF data shows the code set at idle, then my approach may be far different.
And yes, I have seen a few with a bad O2 sensor that caused the same code along with a bucking feeling as the fuel trim was driven to max enrichment.


Check ATF.
Could be due for a trans job.

Re: Honda civic 98 P0170, P0171
 

Well I went to Autozone and it gave me the code

It says Cylinder number 1 denotes bank 1

Probable cause: Large vacuum leak
Fuel system concern
Ignition system concern
MAF sensor faulty
Ho2s/AF ratio sensor fault.

Im not sure if thats what you mean.

Im thinking it was something that i moved when i either changed knock sensor or valve covergasket

Re: Honda civic 98 P0170, P0171
 

No wonder. There isn't supposed to be a P0170 on that car.
I wonder if their code reader is screwy.
I wonder if there is some different code instead, and their reader misread it. Next step is to try a different scanner if it is really a concern, see if the results are different.
You have a 4 cylinder. There is only one bank on it.
Could be, but shouldn't be. A vacuum leak on this type of fuel injection system normally causes the idle speed to rise instead of going lean. (I guess we can find out when you figure out what the problem is.)

Mentioned.
Nope. You'd have misfire codes if it were.
Doesn't exist on this engine.
Mentioned.
No. Freeze Frame Data is a "snapshot" of engine running information taken and stored at the time the code set. It would tell RPM, Vehicle speed, Fuel trims ST&LT, Coolant temp, MAP, Load, and maybe a few other items, depending on the quality and price of the unit. This FF info can be very valuable to a pro like me when it comes time to actually diagnose the problem.

http://wiki.answers.com/Q/What_is_the_freeze_frame_data_in_automotive

This video has absolutely nothing to do with Hondas, but he is working with a Ford with lean codes and he talks about how he uses FF data starting around 2:00 (and I sorta know this person from another forum):

Only the cheapest of the cheapo code readers can't give this data (It's DangerZone......doesn't that tell you anything?)
Better code readers will give this info.
Better yet is the ability to read live engine data as it runs and drives.




DangerZone just gives you a shopping list when they read the code, hoping you'll buy it all. They can't diagnose anything and don't want or need to. This is their business model. Sell more parts.
If the people working there could actually diagnose or fix cars, they wouldn't be working there (most, maybe not all). Same reasoning goes for most tow truck drivers.
Maybe, maybe not. Have you rechecked all of your work?

I sure can't tell you what is wrong from here.