b2600i fuel pressure question

hi, i was doing a tune up on my truck today and decided to test the fuel pressure and i think i have a problem.

book says it should be 65-85 psi but when i checked at the filter it was about 35-36 (perfect for a 4.0 motor but not G6).

my truck runs fine i guess but the whole reason i did the tune up was to get better MPG. its weird, my fuel mileage is always very different. my car is very consistent at 16-17 but my truck can be any where from 13-14 to 16-17. i drive the truck the same all the time, just like i do my car, so i dont get it.

could this be because of my fuel pressure? i figured i would get BETTER mileage with low FP but idk. i would rather have it where its supposed to be.

Well, there are 2 different tests for the EFI fuel pressure and each has their own set of pressures you should have........one of the tests is the "Fuel Line Pressure Test" and here is the factory test for it.



The other is the "Fuel Pump Maximum Pressure Test" and here is the factory procedure for it.





It looks like your right where you need to be if you did the "Fuel Line Pressure Test".

thanks, i actually measured FP with the engine running at idle and without the connector jumped (i didn't know i was supposed to jump it).

is that manual for a 2.6i? i think i have a yellow connector but its the green one thats normally used for diag.

The manual covers the 2.2 (carbed & EFI) and the 2.6 (EFI).
Yeah, the yellow connector is for the fuel pump only.....it turns it on.

There are 2 green connectors......the single green connector is for setting the base ignition timing.......the other larger green connector is for other tests I guess. Here is a pic of all 3 of the connectors that are located near the wiper motor.

explains why i wasn't getting any pressure when i turned the key on. thanks i'll try all that tomorrow

i was wondering what that yellow connector was.

ok, did the tests and my fuel pump is fine but now i'm thinking i should have gotten the injectors cleaned when i rebuilt the motor :/

what kind of mileage are you guys getting with your G6's?

I only get around 5k's /L approx. 12mpg, but I drive it hard, still there's obviously a few other things going on with my Courier. At the mo I'm getting error codes 11, (twice, ) then 17 which I think is air temp & oxy sensors? I try & do the repairs myself to save $, but just talking of injectors - I've heard that the E10 ethanol fuel is best avoided for the risk of cracking injectors?

91 b2600I. I get consistent 18 mpg. Although reading some post, I am low. I see post of folks getting in the 20a.