Corvette Z06 Forum banner

PCM1431-rough idle-flashing CEL

2K views 6 replies 2 participants last post by  racingvette 
#1 ·
Driving home tonight. After about 15 miles the Service light started flashing at a stop light. Idle was rough but not terrible. Code pcm1431CH pulled. As soon as I pulled away, acceleration was smooth and light went out. Thoughts before I start really worrying?
 
#4 ·
I understand that the 1431 code is a tank float sensor which I don't believe is related to the flashing CEL.

20 miles to work was uneventful again. Car felt normal on highway and local roads.

Exhaust pressure out the mufflers feels steady and even. A possible burble now and again.

Only thing I noticed was a slight "fumey" smell sitting at idle. Didn't smell like raw fuel, but just exhaust. No smoke. O2 sensor? Had a pcm0134H code a while ago, but it never tripped the CEL.
 
#5 ·
The 2 issues are not linked
The fuel tank issue is solely from fuel makeup, either can be solved with fuel cleaners or the masking of the electronic card for fuel level float has been eaten too much from the Ethanol and
only float change can solve that. Monitor fuel gauge as to better of not with cleaners

Since your not even posting what year/model, mods or if tuning no one can crystal ball what the exhaust/AFR problem stems from

The P0134 says

Possible causes :
- Faulty Front Heated Oxygen Sensor Bank 1
- Front Heated Oxygen Sensor Bank 1 harness is open or shorted
- Front Heated Oxygen Sensor Bank 1 circuit poor electrical connection
- Inappropriate fuel pressure
- Dirty/Faulty fuel injectors
- Intake air leaks may be faulty
- Exhaust gas leaks
- Dirty MAF
- Needs a PCM tune

O2 sensors older then having 30,000 miles on them are suspect
 
#7 ·
Being stock
I'd suggest cleaning the MAF with a cleaner that is solely for that, most auto parts stores sells
Closely look for any air leak from MAF to throttle body
Assure airfilter is clean
Also get some Seafoam and while at idle, pour it directly into intake manifold to clean up valves and put fuel injector cleaner in gas.
Check fuel rail pressure, should be 58 PSI to see if the fuel filter/regulator is degraded

At 51,000 miles I would replace both front 02 sensors, will not hurt and will better fuel mileage and assure no false AFR reporting to PCM
Places like Amazon have OEM O2 sensors pretty cheap, do not buy the generic types

Just to be sure check the O2 sensors heater fuse in engine bay is not blown and re-torque bolts for intake manifold.

You would be far better off in making use of OBD-II scanner as you then would have known why the AFR is too rich and on-board smog tests such as 02 heaters is failing
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top