Injector sizes?

[Randy960]

You might want to read my other thread first.
Alright, after driving about 200 miles on my new injectors, I got a CEL saying it was too rich. I found this site saying that my original injectors (0-280-155-846) flow 12.9 lb/hr, and the ones I put in (0-280-155-700) flow 18.25 lb/hr. Does anyone know if these figures are right? My mileage seems to have dropped only slightly, I would think it would have dropped dramatically and run really rough if they were really that different.

 

[Bob Ayers]

Why wouldn't you use the correct injectors?

 

[Randy960]

I bought them under the assumption that they were the correct injectors. I had at least one clogged injector that was giving me problems.

 

[fastpakr]

From memory, the 2.9 used 14lb/hr injectors, the early OHV's were 17 and then 19 (something like that - there was a switch to a larger size for SEFI), and I'm not sure what size the OHC engines used. 13lb's/hr wouldn't be enough fuel. I don't think the injectors are the problem. Sounds more like you need to chase down the troubleshooting process for whatever code number you got.

 

[Randy960]

13lb's/hr wouldn't be enough fuel. .

thats what I was thinking, but keep in mind that my 98 is a returnless style system that runs at 56-72 psi

 

[AllanD]

The early 4.0's use exactly the same injectors as the 2.9's.

EXACTLY the same.


AD

 

[Randy960]

so what about a 98 4.0? Every flow rate table I find says my original injectors flow 12.9 lb/hr at whatever pressure they test them at.

 

[Randy960]

I'm guessing that the 18.25 lb/hr injectors were used for the SOHC 4.0, and from the time they switched to the returnless system in 97 to the end of the OHV engine in 99, rangers used 12.9 lb/hr injectors.

 

[AllanD]

"Early" 4.0 means early 1990-92.

the '93-95-? used larger injectors
Because they switched the Cali-Emissions 4.0 to SEFI in 1993
and they needed to deliver the same ammount of fuel in a shorter period of time.

SFAIK they didn't change them again on the OHV.

On the SOHC? I haven't a clue...

AD

 

[Bird]

"Early" 4.0 means early 1990-92.

the '93-95-? used larger injectors
Because they switched the Cali-Emissions 4.0 to SEFI in 1993
and they needed to deliver the same ammount of fuel in a shorter period of time.

SFAIK they didn't change them again on the OHV.

On the SOHC? I haven't a clue...

AD

93-2000 = 19#

SOHC = 24#

Bird