Howell TBI code 44

[OldBarnBronco]

I bought this system last summer and it worked great the first few
months. Now however I regularly get a code 44 and it runs rough and my separate AFR gauge drops to 10. It’ll run great the first time I take her out but if I shut down and then start her up again the she quickly throws the code 44 lean condition detected. Fuel pressure is 10-11 so it’s ok. I checked and cleaned grounds and hot leads and all looks good. One other weird thing it does is when I plug the code reader into the ALDL link and turn the key to the run position I hear a rattling type sound in the throttle body and then I see gas leak out around the throttle shafts. It’s not running of course only the key is in the run position. Thanks for any help.

 

[Broncobowsher]

Old GM TBI codes. That has been a long time. But that fuel pressure sounds low. I thought it was closer to 15.

Also, that fuel pressure. Is that static or dynamic? What does the fuel pressure do while driving? Remember that this isn't port injected, there is no manifold vacuum reference element to the fuel pressure. It should remain stable from idle to redline under load.

 

[OldBarnBronco]

It’s static unfortunately as the gauge is under the hood. I’ll probably see if I can’t run it in cab at least temporarily to see the dynamic pressure. I agree that it is on the low side but supposedly within the acceptable range.

 

[OldBarnBronco]

Test run results are:

Start up from partially cooled engine 11-11.5 psi. After complete warm up and 6 miles approximately a hair below 10 psi at shut off. Pressure fluctuations were about 1 psi while driving. I can see that with several hard throttle situations it might drop below 10 into the 9 range which is supposed to be the lowest acceptable limit. Heck maybe it might drop even lower occasionally. Anyone have ideas to raise pressure a few psi? I’ll be calling Howell tomorrow as well. Thanks.

 

[Broncobowsher]

Pinch the return line. Does the pressure spike? I've seen pumps that can't make enough pressure to open the regulator.

 

[garberz]

I just removed a Howell system from my buddies Bronco. He had a fuel pressure gauge in the dash. Always ran right at 15psi. The pressure would start to fall from excessive heat, and would vapor lock. Once the pressure got to less than 10psi, it would shut down. We re plumbed the fuel lines, problem solved. He’s since gone to FiTech, seems happy with it. It’s a lot more tunable.

Mark