69hondo
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My rv didn't pass smog. Hydro carbon way to high at idle. Any ideas? It has the cat still. This is a 2000 Worhorse chassis with the 7.4/454 mpi. No engine light on.
Oil change too....PLugs, wires, cap, rotor and air filter all new prior to the test. I will check the PCV valve. forgot about that.
2 speed idle testSmog an RV? Only in California. lol
definitely flow the injectors. especially if this is an RV that doesn't get used regularly......old fuel is murder on efi systems.HC's are unburnt fuel, look for anything associated with that, such as a fuel pressure regulator or even a stuck injector. Try and see if you can borrow a good scanner like a tech 2 and watch real time fuel trim, both short and long term. Being branded a gross polluter isn't a good thing... more than likely its something simple...
Oil change too....
Rv camSounds like your rv needs an .650 lift cam swap
Wont be able to get to it until the weekend.Any luck
High desert, Hesperia.The beauty of modern fuel injection is that with scan data (and someone knowledgeable observing it) and a few pinpointed tests based on the scan data...it can be positively diagnosed. Where are you located?
New fuel pressure regulator and new full exhaust.
Two new cats.including a new cat?
Two new cats.
Did you have an issue with longer than normal cranking time on a cold start? Or…does it fire now with shorter cranking time on a cold start? That would be an indicator the Regulator was leaking fuel into the plenum…could have killed the cats I guess…I’m trying to figure out if the cats and regulator were both bad, or maybe just one or the other.New fuel pressure regulator and new full exhaust.
Smog Depot, looks like we're neighbors. New cats can easily mask an actual issue. I've seen many a car come in for driveability concerns that had a new cat that some shop tossed on to get it through smog. Who recommended the cat?Two new cats.
Exactly, I'd like to see what the O2's are doing. Are the switching or are they are they pegged lean or richEven an engine without cats should not have HC’s at that level. I believe he had a lean misfire at idle caused by low fuel
pressure. When the rpms went up the HC’s went to normal. The dumping of raw fuel in the cats at idle could have taken them out.
Ah, I blew right by that post. Good deal.The regulator killed the cats.