Help Please CEL 25 and Failed Emissions

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Feb 1, 2008
Burbank, CA
Hey Everyone,

Need some help.

Last week i tried to smog my newly purchased 94. It had the CEL light on, so I pulled the battery cable off and got rid of the light for the time being. By the way the paperclip method showed error 25. It failed smog because of high CO both at idle and 2500 RPM and high HCs at idle.

I did some research and it looked like i needed a tuneup. Today I changed both O2 sensors, spark plugs, wires, rotor, cap, PVC valve and I gave it fresh oil. Also, i added a bottle of BG 44k on the last tank before the oil change.

By the way, one of the vacuum hoses coming out of the EGR valve was plugged with a small metal ball. Not sure if this was intentionally done by the PO or his mechanic.

I again pulled the battery cable to see if the CEL is come back on and offcoarse CEL 25 showed up after about 30 minutes of driving.

What else can cause CEL 25. I cannot register the car without a smog certificate and and dont want to keep going to the smog station and leaving with a failed result.

Any advice is greatly appreciated.

From the FSM...

Code 25 Air fuel ratio lean

Engine ground bolt loose
Open E1 circuit
Injector circuit
Fuel line pressure
VAF meter
PAIR system
Heated O2 circuit
Heated O2 sensor
Ignition system

That's about all I can do for you. I have never thrown this code so I have no experience with it. Sorry.

From your post here and the other pics you posted, it looks like someones done modifcations for a reason unknown to you. First, I would remove the ball in the vacuum line unless you know why it's there (?)

However, what you should carefully look for is the contact between that main wiring harness and the EGR pipe. It gets real hot and troubles and fixes have been well-documented here.

Pull it up as much as you can and make sure that the wires, especially the ones that contact the pipe are still intact. Pretty common problem, easy to remedy but a little tight space to work in.

Good eye finding that though, it's not an easy place to spot. Good luck.

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