`97 Taurus with DTC P0133, P0420, & P0430

I have a`97 Taurus GL with the standard 3.0 V6, auto with 114k miles. My wife's car. Bought it new, getting the CEL on most of the time. Sometimes when starting the car it will surge or stumble and die. This is very infrequent but is part of the problem. The ISC was replaced for the surge/ stumble problem which improved it but, it is still there. The cam posistion sensor has been replaced twice in its lifetime.

Scanned the codes and got the three mention in the subject line. Has anyone experienced this DTC combination before? Should I look for chafed wiring problems, vacuum leaks, or ....? Is iy simply time to replace the O2 sensors?

Thanks in advance for your help.

try cleanning the MAF

I will try cleaning the MAF.

Thanks,

KingRanchMan02

I have '96 Taurus with P0430 code - sorry - what is MAF? Thanks

Mass AIr Flow sensor, it's located in the air intake snorkel/ductting

Thanks - maybe you can help me diagnose some more - I have P0430 OBD code for several months - I have previously changed one downstream O2 sensor (don't remember which side) due to O2 OBD code, also EGR and related part (DF??) changed due to ODB codes by mechanic.

Currently symptoms/status:
1) pinging - fair amount
2) poor acceleration
3) P0430 code
4) last repair was transmission overhaul ($2000! argh! ended up being a broken $25 clip inside the tranny!) and EGR work - 430 code was present at time of tranny work - but decided not to fix/replace cat system for another $600 - mechanic suggested I replace other downstream O2 myself.
5) I have printed out your P0430 Trouble Code FAQ.
6) 85k miles, original engine/exhaust system
7) can't remember the last time I changed the air filter
8 tried some fuel additive - and pinging seemed to subside for about 4 days - now its back

I bought a downstream O2 sensor at AdvanceAuto last night with intention of replacing this weekend.

Plan
1) clean the MAF - don't know anything about this - how do I clean it?
2) check for exhaust leaks? how? just listen?
3) trying replacing other O2 sensor - passenger side downstream

I have a VOM but not a scope.

Any suggestions/comments will be greatly appreciated! Thanks!

lots of posts on cleanning the MAF in the froums, use brake and parts cleaner and after removing the MAF, spray the wires inside the MAF with the cleaner, let it dry, clear the codes and redrive it. If you have a K&N filter throw it away, it'll cause your MAF to fail. If you have pinging and poor acelleration how long ago was a complete tune-up done? did you use the proper plugs?, improper plugs can cause pinging, codes etc.
Was the egr valve replaced ?
good luck and keep us postted

Jeff

Well, finally got around to cleaning the MAf on my wife's car. It certainly did not look dirty. Did not clear the codes. Will the CEL eventually go out if this was the problem?

if it is in fact the cause it might clear the cel itself! What about the tune-up info?

I also cleaned my MAF using electical parts cleaner - did not see any dirt or dust in it - but wire posts and springs did appear shinier after spraying several times from both directions.

Airfilter is a Fram - didn't appear very dirty - so I left it in.

I bought six new plugs - have changed the front three - working on the back three.

Also put in another bottle of fuel injector cleaner in the gas tank - second bottle in two weeks.

Reset OBD codes at AdvanceAuto - no CE light for four days and counting!

Pinging seemed to be gone immediately after cleaning MAF - but seems to have returned - might be subjective - notice that pinging occurs most often after accelerating, taking foot off of gas to make turn, then pressing gas pedal again - almost like car is not downshifting when it should or could to get better performance.

Would changing PCV help pinging?

EGR and DPFE were both replaced at time of tranny service.

If Cat Conv was bad, would exhaust "sound" different?

Have not replaced O2 sensor downstream of passenger Cat yet. Could bad O2 cause pinging?

Thanks for your help.

O2 could cause pinging if stuck at one extreme I suppose! What brand of DPFE and EGR? Has the fuel pressure been checked? Cat failure might be heard in the exhaust if the catalyst came loose but if it's restrcitted then not as likely! Changng the pcv is not a bad idea at this point! Plugged ports in the throttle body, intake, egr tubes etc could still be an issue, might require a more aggressive fuel cleaning then just pour in cleaner. Might still be a MAF issue if it's not giving the correct baro reading even after cleanning

Hi Jeff - thanks for answering my questions...What about SeaFoam engine cleaning solution? I saw one website that couldn't say enough about it.

I will hold off on the O2, and try the PCV (much less expensive), and keep my fingers crossed on the code returning!

Myself personally have never used Seafoam but have heard nothing but excellent things about it. You might want to try a backpressure test in the exhaust or using a vacuum gauge on an intake port to see if the converter
isn't plugged or restrictted somewhat! What brand of DPFE and EGR, because you could have been on the right track for the EGr and now a parts interchangability or poorer quality could be causing you to go in circles, Wells brand seems to be a pretty poor alternative to dealer parts!
From what I've heard anyway. Check the fuel pressure like I said and if possible get a load and or a BARO reading from the engine with a scanner
that will tellyou whether the MAF is now accurate or not

Good luck and keep us postted

Jeff

Tune up was done last fall, IAC replaced at that time as well. Engine runs good, only problem is the CEL with these codes and an occassional stumble and stall on startup but, this is infrequent.

maybe an 02 and or converter problem then