hacker-pschorr

My car is running rich, at start-up it takes about 10 seconds before my garage smells like gas spill.

After a long drive (see fully warmed up) pull into the garage, it's spitting out as much fuel as it does on startup.

At WOT my air/fuel gauge is way in the green (rich), in all gears/rpm's.

I know an adjustable fuel pressure regulators would work, turn down the pressure. I'm looking for any other ideas.

My car still has a CAT, it's not clogged.

Tim Murphy

Sounds like you have a leaking injector, a wiring problem, or a barn door issue.

If i remember right, you had a plug that was continuously getting sooted up so I would start with that injector first. Try disconnecting that injector plug and see if the car leans out past a stoich condition. If it leans out then the negative side of the injector coil is seeing a constant ground. If the AF has no change then the injector is stuck open.

Greggles

Anyone know how to lean out an L-jet car?

Atkins & moderate exercise

hacker-pschorr

Funny thing is, last night I replaced the #1 spark plug, now it's running a tick or two richer than before. Same plug the rest are, just got rid of the fowled up one.

Jim bailey - 928 International

workshop manual section 24-24 describes in some detail drilling and removing the metal plug in the squarish metal casing near the end on the air flow meter. The CO level rich lean can then be adjusted somewhat using a screw driver ;clockwise is rich , counter clockwise lean . Press in a new plug when done . HOWEVER often the black plastic cover has been removed and glued back on during prior "tuning sessions" because it is too easy to bend the little arm which rides on the contact strip when the door opens and closes to "adjust the mixture" . Much easier than finding real problems but makes it quite difficult for the next guy !

hacker-pschorr

So much for the guy that cleaned out and tested my injectors. Wires are ok from the coil over. Tested on a different car.

Yea, but the soot looks like oil buildup, not fuel. Other than the buildup, the actual center of the injector looks like a clean burn. Jim took a look at it last night, he's 99% sure it's an oil leak.

I'll play with the injectors tonight and the AFM tomorrow.

hacker-pschorr

I just remembered, I attached the barn-door from my neighbors car earlier in the summer (he wanted to try mine to figure out a miss in his engine) During the swap, neither car ran any different. So either both of our flow meter's were tampered with the same way, or they are probably both stock.

Any chance a fuel pressure regulator or fuel dampner are not working correctly and punching up the fuel? Guess the only way to know this is a fuel pressure gauge.

ViribusUnits

Yep there is deffently a chance the pressure regularos, or return lines are at fault And yep, the only way to know is a fuel pressure guage.

Garth S

If you are focusing on one cylinder, a compression check can't hurt.
If it is a sudden onset of general rich operation, then the usuals are the injector failures as mentioned (electrical to ground, or mechanically stuck open), ditto for the cold start injector - and its partner, the temp II sensor.
The AFM would not normally 'jump out of tune' if the car had been running OK. How is the O2 sensor? At WOT, the second micro switch on the throttle body drives the ECU rich anyway - although you suggest it is going beyond 'rich' - to raw fuel.

Bill51sdr

Fuel pressure regulator is a possibility, but check the fuel pressure before just blindly replacing it. I repaired/smogged a Ford Exploder that was just dumping fuel due to a faulty regulator. HOWEVER... your fouling plug/cylinder could be at the root of your problem. That cylinder could be driving your oxygen sensor nuts. When that plug misfires, you are sending a healthy dose of oxygen past the O2 sensor, making it detect a 'lean' condition. The ECU's response to that is to RICHEN the mixture... a vicious little circle you may have going there. You may have to live with this until you address the problem with that cylinder. NO amount of AFM adjustment will compesate for a problem like this.

hacker-pschorr

Just so everyone understands, my car runs fine. There would be no issue if I did not install the air/fuel meter, other than the gas fumes. I'm looking for ideas and other people's experiences on these cars to make sure I'm not missing anything real obvious.

Compression is good on all 8 - checked earlier this year.

As for injector wires going to #1 - back when I first got my engine back together, I found a bad injector. At that time I was swapping around injector wires, including this one. So unless the harness is bad and every line on my right bank is misfiring, the connection going to #1 is fine.

PorKen

Stuck/leaky fuel injector(s)
Leaky cold start injector
Bad cold start injector thermo-time switch - unplug thermo-time switch
Bad oxygen sensor - unplug O2 sensor
Grounded oxygen sensor wire - unplug O2 sensor
Bad Temp II sensor - check ohms when hot
Resistor inline of Temp II sensor installed by PO (my car)

Here's the factory 'manual' for L-Jet as jpegs with testing procedures:
1980 L-Jet Service Bulletin (2.3MB, scanned/zipped, right-click, 'Save Target As...'): LJet_AFC.zip

John..

Hacker, pull off the cover and put a few more ticks into the black wheel to tighten up the spring and see what happens. I think the bypass screw just sets CO at idle. You'll need to change the spring pre-load to change the whole curve. No harm in trying it.

hacker-pschorr

Just for the hell of it I unplugged my WOT switch for the 7 mile drive home after work.

Well, if that switch ever fails, I'll know what it feels like. That did not lean out the car, just made it run like sh*t at anything over 1/4 throttle. Actually, it did peg my air/fuel meter in the "lean" for a while at WOT then starting bouncing like psyco x-mas lights until I let off. I wasn't expecting anything specific, just felt like trying something.

You do weird things when you know the engine is coming out/being replaced in less than 45 days. Nothing to loose, right?

toofast928

Have you looed at the EVAP hoses in the RT fender? A cracked hose would yield a fuel smell.