BANSHI

Honda crx 91, dualpoint injection, manual transmission. I just went and got Emissions checked. I failed on the Fuel pressure test and Hydrocarbons, carbon monoxide test as well. I Just did a head gasket swap and remember releasing the fuel pressure but I don't think I did it right.

Please help

I have no idea where to begin with these problems.

Any ideas or advice is much appreciated.

Former User

The fuel pressure must be too high. What was it?

Stock or aftermarket fuel pump?

Fuel return pipe clogged?

Bad FPR?

BANSHI

RonJ@HT, I Think its a Stock Fuel pump. And the FP test failed because it wasn't able to hold any pressure, they said there was a leak somewhere.

Stupid question, what is FPR?

Former User

Locate the gas leak by smell. Turn the key to ON(II) to pressurize the system. Where do you smell gas?

However, while a gas leak would lower fuel pressure, it wouldn't cause the engine to run rich. That's a separate problem. But fix the gas leak first.

BANSHI

That's the problem, I don't smell anything at all, not even the slightest hint of gas. Is there something I could check and tighten to make sure it holds the pressure right?

Former User

Were you told that there is a gas leak? What exactly did they say?

There must be some fuel pressure otherwise the engine wouldn't run.

BANSHI

All those tards said was that it didn't pass FP because it wasn't holding enough pressure. I asked what it could be and they said there could be a vacuum leak. maybe those morons blocked off the wrong hose.

Former User

The fuel pressure regulator (FPR) controls fuel pressure. It uses vacuum from the intake manifold to do this. If the vacuum hose to the FPR were disconnected or blocked, the fuel pressure would be too high not too low.

BANSHI

Okay Ill get right on it then, checking all the vacuum lines. Anything else for fuel pressure? Now as for my HC and CO failed test. What could I start looking at. Could I be off on my timing belt? causing it to be rich? could it be because I seafoamed it and didn't really give it enough time to clean out?

Former User

The most common cause for low fuel pressure is a clogged fuel filter.

A bad fuel pump or bad FPR could also cause low fuel pressure.

Former User

Low fuel pressure is inconsistent with running rich.

Start by doing an ignition system tune up (plugs, wires, cap, rotor, ignition timing).

When both HC and NOx are high, it's usually a sign that the cat is dead.

BANSHI

Hydrocarbon, This vehicles emissions (2.00) Applicable standard (1.00) Failed
Carbon Monoxide, This vehicles emissions (19.68) Applicable standard (12.00) Failed

these are the results for emissions.

where to start with these issues?

BANSHI

what's cat?

Former User

Catalytic converter (cat)

Please read my posts.

BANSHI

Alright then, here's the game plan. Plugs, wires, cap, rotor, ignition timing check, clean or replace. Then check my fuel vacuum lines to see if there clogged.

Former User

No. As mentioned, a clogged FPR vacuum hose would raise not lower fuel pressure.

BANSHI

Listen I am so lost on what to do. Im fairly new to this DIY mechanic stuff. I'm really busting my ***** on this one. Could my o2 sensor be bad and cause my engine to run rich? Also how do you check the ignition timing and set it right? how do you check the cap, rotor? what am I looking for? cracks, dirt, dents. Step by step directions please (where to look, what to look for). Ive spent a couple hours looking on the internet and calling up auto repair shops. still haven't got solid advice.

Former User

If you don't know the age of the spark plugs, wires, cap, and rotor, then just replace them. If not old, inspect them.

The diagrams below should help.