Fuel Pressure and Code 44

[Corsair231]

Eric,
This is a problem I'm chasing on my Sy. Occasionally on my Sy at warm idle I will get a code 44 (lean exhaust) and the idle will get rough. Sometimes the truck will even stall. My BLM will be at the upper end of the range which means the ecu is pulling fuel, correct? I have not found any vac or exhaust leaks. The O2 sensor cross counts seemed a little lazy so I changed the sensor. It helped but didn't cure the issue. The truck is driven enough that bad fuel shouldn't be the issue. Another typical cause is low fuel pressure but mine is actually a little high @50 line off and @40 line on with a stock non-adjustable regulator, but I did read somewhere that high pressure could cause it too but they didn't elaborate. I cannot understand how though so I figured it was a typo and it was supposed to read low fp. Have you ever any experience with this caused by high fp?

I've read it could also be a clogged or stuck injector. I've put a stethoscope to the injectors and they are all clicking like they should so is there anyway short of pulling the injectors to see if they are clogged? Could a clogged injector cause high fp? All of my other numbers (iac, tps, etc) seem to be about where they should be and all of the ignition parts to include the distributor itself are newish and seem to be in good order. Just a little transitional knock when I slam the pedal to go from cruise to wot.

Truck has good power and runs good otherwise so I didn't think I have any kind of fueling problem but I'm running out of ideas. I have thought about just upping the idle fuel in the chip but I don't want to crutch a problem that really needs to be fixed.


I've got another issue but I will put in in another post to keep from muddying the waters.

Thanks

 

[EricM]

If the BLM is high (above 128), the computer is adding fuel due to a low O2 reading (lean reading). How high does the BLM go?

Also, so I can look up your chip programming, do you have your chip#? Or you can email me you name, and I can look it up.

Eric

 

[Corsair231]

It maxes out at the mid 140's. I don't have my chip number handy and I bought the chip and 50 lb injectors used. I will try to get the numbers this weekend. I want to try to trouble shoot my trans issue as well and see if fixing it causes any improvement.

 

[EricM]

It's possible some updates to the programming would improve both situations, depending on how old the chip is.

 

[Corsair231]

I unplugged my TCC lock-up solenoid trying to trouble shoot my issue in the other post and this situation has improved dramatically. It has stopped setting off the code 44 every time I drive it. The idle has improved and my blm's are back down into the mid 130's. Every once in a while it will get a little rough idle but I'm thinking it is the converter still dragging a little when it is hot. I am planning to change the TCC solenoid and trans fluid and filter hoping the problem won't come back when I hook the lock-up back up. If it does come back then it looks like there is a new converter in store. I am probably going to change my iac and tps sensors while I am at it.

BTW, my chip code is 1002 according to the paper that came with it. The chip is about 9 years old.

 

[EricM]

Yes that's pretty old. I have made a bunch of changes since then, including tcc and malfunction code stuff.

 

[Corsair231]

Would that be the $65 charge for reprograming? Would that reprogramming cover changing injector size too? I still want to have my injectors checked and if I've got to buy injectors then I might as well upgrade. Are 60's still the injector of choice?

 

[EricM]

As long as its the newer version 2 chip (with the 2 adjustable dials on it), then its $65, and that would cover an injector change. If you have the old first version, then there's only so much I can do with that. I could make small changes, but not an injector change.