EFI running rich

[nephic2]

Okay, so I'm pretty jazzed about my EFI setup being installed, but am running into a few snaffus. I've had it going for about 200 miles and am now wondering if its all up to snuff.

Here's the lowdown:
-302 engine and standard cam
-89 mustang mass air
-new dual flowmaster exhaust
-BC Broncos 24 gallon tank and pump
-used intake, fuel rails, distributor, throttle body, and Mass Air Sensor, regulator
-new wires, O2 sensors, filters, fuel lines,
-same spark plugs
-timed correctly, and seems to generally run well
-idles at round 600 rpm or so, starts first try everytime

When I jump on the gas it seems to hesitate a little before it really wants to rev. In addition, you can look at the left exhaust and it definantly blows a little black.
Today it was acting a little sluggish and it could be my imagination, but was acting like it missed once or twice, and maybe even gave a little backfire.

WTH! I'm a little frustrated. This Bronco has been my first real project, and I'm a little worn at the moment. I just wish that I had all the snaffus fixed for a day or two. I've decided that this is going to be my DD to so I need to get her all tidey since I'm selling my ranger.

Thoughts? How do I even begin to start trouble shooting. And no, I don't have the probst book.

 

[trailpsycho]

Any codes?

 

[nephic2]

I don't have a code reader, so I'll have to see if I can get my grubby paws on one.

 

[Heus33]

I dont know either but judging by your avatar I'm in the wrong Buffalo!

 

[trailpsycho]

Autozone can run the codes for you...if there is one nearby.

 

[SaddleUp]

If it's running rich down one side only then that indicates a probem with the O2 sensor on one side or the other (Not necessarily on that side though). That's the only thing in the system that will make only one bank act different without effecting some cylinders on both sides. Putting 2 different O2 sensors (one short, one long) on is a sure cause of it (Don't ask how I know). The hesitation may be completely unrelated. 600 seems just a tad low for the idle indicating that the timing may be off just a little. (With the EFI Idle speed is largely controlled by timing) If so it could cause it to hesitate and stumble a little.

 

[00gyrhed]

Almost certain you have an O2 sensor problem. Maybe just a bad connection. Buy a ford fuel injection book. You can get one at pep boys, auto zone etc. It will have all the codes and how to dump them using a jumper and a light.

Curious if you opened up the gap on your spark plugs, or did you have electronic ignition before the conversion?

The hesitation is likely due to the rich bank and possible timing issues. Mine idled at 600 but didn't have enough power to feather the clutch with the sensitive throttle set up I have so I just adjusted the idle screw up until it was about 800 or so. Mine also hesitated, and I couldn't get enough advance into it without it being almost impossible to start. I had decided to leave it a lone since it was at least usable and I decided to get my heater ready for winter. I did the Chevy fan conversion for the heater, I also changed the t-stat from the 160 I had put in to a 195. HSMF the whole thing changed, after that. It really woke up. I was suddenly able to set the advance up. hesitation went away. Before the change you had to sit in the vehicle and work the throttle until it warmed up. After that you could stand outside the truck and start it ans it would fire right up and idle.

 

[SaddleUp]

FWIW, if it's just mismatched O2 sensors they will not throw any codes. If it's a wiring problem to them then it might. I've had the rich bank problem twice now. First time was because the O2 sensor (on the opposite side) was dirty. The second time was because I mismatched the sensors. (One long and one short) It didn't throw up any codes either time though.

 

[Pa PITT]

Have you been idling to much ....what kind of spark plugs ....only champion ..autolite or motorcraft....

 

[nephic2]

An update on my issues. Just went through a bunch of stuff. Put nin new psark plugs but I'm curious, Why re-gap? I'm at .030, should I be different. They are Champions. Bought a cheapo code reader, and get this, I can't get the thing to throw ANY codes. Which brings up another interesting issue, the check engine light never comes on, ever. SO... I pulled the computer and checked all the hots and grounds, all checked out. Checked the connections to the self test plugs by adding power and using a volt meter, they're all connected. Rechecked the wiring on pin 17 (check engine), and it looks right. Back probbed the O2 sensors (both brand new matching), they are both sending, checked the Mass air meter, working. Tonight I will open up my wire looms to see that all of the other connctions are alright. I can't figure why I can't get it to throw codes, but I think that when mI find out that will be the basis of the problem, or at least beginning to fix it.

 

[DCarter001]

Sort of as an after thought, you may also want to check your vacuum lines. I swapped a 5.0 into my 94 ranger without changing the vacuum lines and it was dreadfully slow off the line. Ran through a series of code pulling, plugs, checking connections(starting to sound familiar), nothing appeared out of place. Replaced my vacuum lines and life got instantly better. I was actually surprise it was running at all based on the condition of the hoses.

 

[Broncobowsher]

Make sure the engine is well grounded to the body. That has been known to throw a few extra millivolts into the computer and cause a perfectly good O2 to read a little off what it should.