rotorpower27

california standards
Car= 1988 NA GXL.


Replaced so far:
New main cat
New spark plugs
Checked for vacuum leaks
Checked and rechecked grounds
Adjusted the TPS right at 1 ohm
Turned adjustment screw to full lean
Ran Amsoil fuel injector cleaner for about three tank loads.

New items that will be arriving shortly:
New spark plug wires
New fuel filter

Test 1
Some emissions devices where not installed, EGR valve, charcoal canister.
Air pump was directly connected to Catalytic converter
View #’s

Test 2
Reattached all emissions standard devices, and installed air pump to factory standards.
View #’s, wow they got worse

Test 3
Dummy rigged EGR valve.
Installed new items, list above^
Air pump in factory arrangement.
View #’s, the catalytic converter did have an effect on NO #’s.
Hydrocarbon Numbers are similar to first test.


Question:
Why would my hydrocarbon #’s be so high?
What causes this and what to do next?

Thanks for your help

rotorpower27

Question:
Why would my hydrocarbon #’s be so high?
What causes this and what to do next?

Rotary_Powerd

Unburnt fuel I believe. Get Rtek7 and try running richer or even lean it out.

rotorpower27

Maybe misfiring has something to do with high HC, at least that’s what I have dug up by searching.

NCross

iTrader: (18)

check your timing?

NCross

iTrader: (18)

and by "turned adjustment screw to full lean" what do you mean? what adjustment screw?

rotorpower27

timing doesn’t have that big of an effect.

i just checked my fuel rail regulator , and it regulates right at 40psi.

i checked my top two fuel injectors, and they shoot a very nice mist.
i haven’t checked the bottom two, because its a pain
what else could i check

walken

iTrader: (6)

timing has a huge effect. make sure it is spot on. if for some reason it is not or you can't get it make sure your TPS is spot on.