Running Lean?

[SuzaMan1957]

Hi Ya'll, 95' 2.3L 5SP 2WD. Before and after doing a major tune up I noticed that the engine is starving for fuel possibly. When I pulled the plugs they were a little white in appearance which indicates a lean condition. So I decided to check the fuel system. Here is what I got.
KOEO.....35-40.lbs but the pressure slowly drops.
At Idle....30.lbs with vacuum on regulator
At Idle....40.lbs without vacuum on regulator
FYI....replaced fuel filter, PVC, EGR System checks out fine, 20.in of steady vacuum off the intake. Getting 21 mpg. I'm thinking about replacing the fuel regulator. Any thoughts?

 

[Bryan22]

not sure if they run lean or the dual plug setup causes it, but my plugs are always on the white side when i change em. sounds like everything checks out fine.

 

[SuzaMan1957]

I was concerned about the drop in fuel pressure @ KOEO position. Thanks

 

[Bryan22]

missed that part. you ever have trouble starting it after it's been sitting a while? like it cranks longer than usual? How slow is "slowly drop"? really though i don't see it being a problem since it is right where it should be when running.

 

[SuzaMan1957]

It has been starting/running fairly well. From a cold start.... it purrs. It just seems like it shudders a bit when idling after it has warmed up. The pressure drop takes about 60 seconds to go below 10psi.

 

[modelageek]

It has been starting/running fairly well. From a cold start.... it purrs. It just seems like it shudders a bit when idling after it has warmed up. The pressure drop takes about 60 seconds to go below 10psi.

it should drop about 6 psi in 5 minutes. You probably have an issue with your check valve, add a bottle of Techron to the tank. I think the check valve is in the FPR regulator but I am not positive.

 

[Ranger44]

I think you should measure fuel pressure when it's running, and you should check it when it "shudders".

As for lean....my plugs on my 2.3 always seemed a little white.

The clogged fuel filter could have caused it to run lean at times.

 

[modelageek]

It has been starting/running fairly well. From a cold start.... it purrs. It just seems like it shudders a bit when idling after it has warmed up. The pressure drop takes about 60 seconds to go below 10psi.

for the shudder, makes sure you air filter, pcv,plugs and wires are good, clean the maf,TB and IACV. and reboot the PCM afterwards....

 

[kimcrwbr1]

If it starts good it is probably not injectors it could be the regulator or fuel pump I believe the check valve is in the pump. Add 4 ozs of acetone to a full tank of gas will also scrub the fuel system it will dissolve any varnish built up over time. If you dont smell fuel on the dipstick and it cold starts easy run with it 21 mpg is pretty good.

 

[modelageek]

I think you should measure fuel pressure when it's running,

He did!

So I decided to check the fuel system. Here is what I got.
KOEO.....35-40.lbs but the pressure slowly drops.
At Idle....30.lbs with vacuum on regulator
At Idle....40.lbs without vacuum on regulator

Those are good #'s........the only issue is the pressure drop KOEO...I think the acetone or TECHRON might take care of that.......

 

[kimcrwbr1]

the shudder could also be an intermittent short or loose connector look for bare cracked wires and clean/dielectric all the connections and sand the grounds.

 

[SuzaMan1957]

Great feedback! I will try the acetone and will check out some of the components ya'll suggested. "TB" does that mean Throttle Body? Thanks

 

[BLS2.3]

Acetone or run a bit of E-85 mixed with your gas (~10-15% E_85) for a couple tanks.

Yes TB = Throttle Body.

 

[Bryan22]

if i were you i just wouldnt worry about the slow pressure drop. it starts fine, it runs fine, fuel pressure is within spec. just drive it.

 

[SuzaMan1957]

Thanks!!!

I agree. I'm going to drop some acetone in the tank and then I'm done with it. Everyone thanks for all the help, I appreciate it.