eeppower58

So Im on the fence about things that could be wrong with my jeep. I had one mechanic tell me that all I needed was a new CAT and then I went to a muffler shop and he looked at the emissions sheet and saw the numbers and said I have engine issue and it's getting to much gas any help please?

frumundacheeze

post the numbers

eeppower58

For HC

Max=123 meas 178

For CO

Max=0.73 measured 2.83

For NO

max=711 measured 848

Slick761

I'll show you what smog shop to take it to lol.

frumundacheeze

High CO, HC, mid to high NOX check the O2, vacuum leaks, ignition timing and CAT

eeppower58

Next to ihop right? But the guy at the smog place to test it again it would only be 20 bucks

rrich

She's too rich - too much fuel - hi CO - check the vacuum line to the fuel pressure regulator - main reason for these to be too rich. Get CO down the rest will drop with it.

Slick761

I have a coupon for ya.... anyhow well run sensor diagnostics Thursday and go from there? I might buy a fuel pressure guage kit soon but if it comes to that we can rent one.

nielsenml

I had a similar test last weekend. Cleaned air filter, 1 can of Seafoam($8) in 1/2 tank of gas, new plugs ($12) and a o2 sensor ($52).. the 91 passed with flying colors.

Don't know which did the trick as I tried them all at once. LOL.. I suspect the o2 as have been original equipment though. Looked very unfunctional.

frumundacheeze

also before you take it in next drive the hell out of it get the cat nice and hot to allow it to do its job, let it sit and idle while you wait your turn, believe it or not it helps alot, also if you haven't done it recently change your oil, also makes a difference.

Slick761

Eepower check out san Francisco bay area monthly meet thread in the pacific northwest section of the forum. Were trying to get bay area cherokees to meet up.

eeppower58

That would be sweet I'll check it out

eeppower58

Thanks alot guys for the help

Slick761

Anyone ever had voltage too high to the fuel pump/bad ballast resistor?

rrich

Theoretically a higher voltage to the pump would make it spin faster - more pressure. BUT the pressure regulator would cut it back down.
All it really would do is shorten the life of the pump.

The pressure regular uses manifold vacuum, it's job is to maintain fuel pressure in the rail a set pressure above manifold vacuum.
the proper test -- compare fuel pressure in the rail compared to manifold vacuum. It should remain constant no matter what the speed or load.
If the hose leaks, or the regulator is defective, it will give too much fuel pressure - HI CO!