Great truck, I love it, but it's time....

Just had the rear brakes replaced, not too long ago had fronts done. Just about everything replaced. But since the rears were done, when you brake to a stop under a load, going downhill, it bumps, shakes and bounces like Mr Toad's Wild Ride. What's up?


Next, check engine is on....my neighbor has a "code reader" and it says it's "left bank, right bank too rich" ... Sounds like injectors to me? 130K on it, should I try to have them serviced or just replace the bad boys? I hate like hell to go in blind to Ford, I like them and all, but it's always 500, 1500, or 3500! I'd like some background before I go in.
As always, thanks for the great advice I get here!
mw

 

On the brakes were the rotors removed or machined?Sometime improper machining can cause this.Also foreign material between the rotor and hub will case it.Overtorquing the lug nuts will cause it.The check engine light sounds fuel related or intake air related if it's rich on both banks.What we prefer is the code #s not what the scan tool reader said.A clogged air filter will make it run rich but it would most likely run poorly also.A bad pressure regulator could raise fuel pressure and make it run rich as could a restricted return line.

 

Your going to waste a lot of money approaching it that way. It's not bad injectors. It's a control issue somewhere or a bad regulator. You really need a scanner to diagnose this correctly. You need to look at all the sensor data and analyze what's going on in there. You need to look at things like Mass air flow/MAP sensor readings, short and long term adaptives etc. Pull the vacuum hose off of the fuel pressure regulator and see if there is any fuel in it.

 

thanks guys....I really appreciate the advice...the code #s were 171 and 174. Don't ask me how, but I remember that. It does run rough at idle sometimes, then it smooths right out, then it runs rough again and sometimes it stalls. Starts right back up again like nothing's wrong.
Does that help pinpoint it a bit more? I'm glad I might get a repreive on the injectors.
mw

 

No, not really. It's obvious that you have an over rich condition. You need to look at many other things to determine what might be causing it. There could be many causes and any diagnosis would be nothing more than a wild guess and probably wrong. Check the fuel regulator vacuum for fuel. If you have a MAP sensor, check the vacuum hose, mass air flow sensor?....many more possibilities.

 

Can you believe that your engine oil dipstick not seated all the way in will cause these codes? Its true. There is an entire page of items that can cause this. From excessive fuel pressure to leaking injectors to a sticking EGR valve. And these are only the ones listed. Most likely a vacuum leak, but you really should check everything before you start throwing parts at it.
Billy

 

These two codes are Lean codes = Check for a vacuum leak on the PCV valve Hose or a MAF sensor that is contaminated. P0171 and P0174.

 

He's right. those are lean codes not rich.
That changes everything.

 

You were all on target. Vacuum leak, and PCV valve shot. All done, all good, thanks again....once again, a valuable site indeed!

MW

 

What did you find out on the brakes?The more important one from a safety aspect.You can get going real well now but you still need to be able to stop safely.

 

have not tackled that one yet Davo...trying to get it in to the brake guy today or tomorrow....The rotors were replaced....nothing used was machined. The foreign material might be it or maybe the over-tightened lug nuts....can you over-tighten with an air wrench?

 

With an Air- Impact, ABSOLUTELY!!! Will warp even new rotors.
Billy

 

Take a look in your owners manual, it will list the torque specs for the lug nuts also depends on the type of wheels you have, steel or aluminum. The lug nuts should be tightened with a torque wrench to the specified value, not as tight as possible.