P0174 and rotten egg smell exhaust

[John H]

I have an 01 edge 4.0 auto..the hoses that usually crack and throw this code were fixed awhile back and are still in good shape. Truck does run rough and idle surges. My question Is can a bad/clogged cat cause the p0174? I've been told to replace the cat but don't want to spend the cash and it not fix the problem. Also my MAF has been cleaned but the code is back after a week of driving. Thanks for any help

 

[John H]

Need to clarify..I cleared the code after I cleaned the MAF

 

[okietheranger]

Check fuel pressure

 

[John H]

Update:

Put it on a scanner saw #5 plug misfiring,pulled it saw it was black. Installed a new one,scanner still showed a slight misfire so poured seafoam in brake booster vacuum line to decarbonize engine..I'll drive it a week then take it back..if it still looks bad we'll look at the injector,I hope it's not a problem with a valve

 

[pcollins]

Rotten egg smell is a pretty typical sign of a bad cat.

 

[okietheranger]

Rotten egg smell is a pretty typical sign of a bad cat.

I wouldn't say that. Unburnt fuel will do that sounds about right scenes he said number 5 wasn't fireing

 

[okietheranger]

I just had a hell of a time getting ride of that same code. Bought the truck off some guy for cheap cause it had engine noise (all the timming cassettes wasted) after fixing all that and replacing the mains and rod bearings cause the little timming guides are plastic and when they all broke just about clogged the oil pickup. Engine ran great no check engine light on found out its been on so long it burned out. So fixing that found that code po174 I belive that's bank two lean. It wasn't a vacuum leak cause I just re gaskets the whole engine wasn't the mass air I seen the previous guy replaced that alonge with the o2 sensors so I got a little stumped. Was able to get a hold of a better scanner and was able to watch fuel trims they were good at idle but went off at higher rpms. So I checked fuel pressure was good at idle but lost a couple of pounds at higher rpms. Sure as shit the truck ran great just that code. Replaced the fuel pump and bye bye code . Not saying that's ur case but just good to keep in mind. If only one cyclinder is dumping to much fuel I would say possible injector or it's black cause no spark. Just throwing this out there

 

[John H]

Update

ok I still have the problem with #5 showing a missfire..replaced injector,sparkplug,plugwire,and swapped coil pack. codes are p0174 and p0151,tomorrow gonna do compression test and see what it shows..im starting to lean towards a bad valve. Forgot to add that earlier it started shifting real hard,I've experienced that with the MAF unplugged..mine is connected and cleaned. Was thinking it might be bad but that wouldn't explain the miss on #5. UPDATE... compression on #5 is 115,swapped in a good MAF as well still has the miss/rough idle so on monday gonna pull the intake and check it...Any other ideas? thanks for the replies.