Which BLM Cell?
Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
It depends on what you're looking for - Vacuum leak, for example, has less need for fuel as load and rpm increase, so the Lean you see at idle will be diminishing in the other Cells. A rich injector would show the opposite. You should also look at the Integrator and since the BLM is stored in memory, take a look before you start it up to catch any trends. Once you identify a Rich or Lean condition, use the Diagnostic Aids for a 44/45 to find the problem.
Thread Starter
Instructor
Joined: Jun 2004
Posts: 247
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From: Derry nh
Thanks for your response. My BLM at cruise is high (144-152) but at idle is fine so I don't know what else to look for. Checked most everything I and others can think of.
What do you mean by "use the Diagnostic Aids for a 44/45 to find the problem."?
What do you mean by "use the Diagnostic Aids for a 44/45 to find the problem."?
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
A 44/45 are Trouble Codes for a Lean/Rich Exhaust - If you don't have the Code, the Diagnostic Aids in these Charts cover all of the possibilites that can cause either condition. Yours is Lean at Cruise. I would guess injectors or a restricted fuel filter or lack of gas (regulator).
Thread Starter
Instructor
Joined: Jun 2004
Posts: 247
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From: Derry nh
Injectors were just replaced with F.I.C.s Bosch Design III and fuel filter was changed. Performance and mileage are back to what they used to be before the Multec injectors died. Fuel pressure is in spec at idle and WOT. Would like to check FP at cruise on the highway though.
Don't know what the BLM was prior to injector replacement but remember being told it "runs a bit lean on the highway". The EGR has been removed and I'm thinking of putting it back which may or may not alter the cruise BLM.
Don't know what the BLM was prior to injector replacement but remember being told it "runs a bit lean on the highway". The EGR has been removed and I'm thinking of putting it back which may or may not alter the cruise BLM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
What's the Int? EGR, if properly disabled, shouldn't be letting in anything and if it isn't, you'd more than likely see it at idle. Posting the full scan - idle/cruise - might give us something. Checking pressure when the problem occurs is a good idea.
