I have a 91 dak sport 318 and i noticed it was running kinda funny today. So i did the key dance and checked the codes i got a running lean code (51)

So my first question is we recently just dropped temp alot here in iowa with the so called "blizzard" Could that have an effect and is it something it may just come out of?

The plugs and o2 sensor have been changed in the last couple of months. what else should i look at to cure this? (i also have the one step colder plugs which seem to work alot better)

any insight would be appreciated.

Also how do i go about checking fuel pressure to determine if its my pump or not? I have a gauge just dont know where to hook it on this motor/truck.

 

Yes check fuel pressure. Get a fuel pressure gauge and plug it in and see what you get while it is running bad.

 

that truck is a TBI system (last yr before the Magnums) that has 2 injector showerheads mounted in a throttle body that very much looks like a carburetor...and were known for having 1 injector quit spraying,,, whether due to electrical issue or clogging taht would certainly make it run lean

 

I already have a fuel pressure testing gauge and all the different attachments. I was not able to find the valve that it screws onto earlier when i checks. Or am i gonna have to use the barbed fittings and clamp onto my hose between the fuel line into the tb

 

yup barbed fittings there is no place to screw in anything on a TBI. and the pressure your lookin for is only 15+/-1

 

okay, now before i go testing a bunch of things i now have a different question. There is a black wire (prolly 8 or 6 gauge) that comes from my battery and goes into the massive tape mess of a bunch of wires. im assuming it feed directly into the dist. box... in the middle of the black wire there is a what i call bullet style connector.

last night i had no jucie and turned out to be if i wiggle that connector a bit everything went back to normal. she is running better too.

can that wire cause me to run, but not run right or run lean (my theory is improper voltage to the rest of the system including fuel pump = weak pressure)

 

yeah that can cause a bunch of weird issues, often the retainer tab gets broke take it apart and check for corrosion put it back togetehr as tight as itll go and tape the hell out of it to be sure it stays there

 

yeah its real bad right now, i think im going to look for some connectors similat ro that and just crimp/solder on new ones and then heat shrink it. it sucks having to wiggle that wire just right everytime i go to start my truck, but gotta love nothing being open on the holidays!

btw Happy holidays!

 

another theory i have is just splice in a 100 amp fuse (i have an agu fuse holder for 8-4 gauge wire and a 100 amp fuse left over from an old system) would this work? It would still give me the ability to disconnect as well like the "stock" setup? or would that be a big enough fuse? idk what kinda amps pull through that wire but it seems to be the basis of everything from the starter/ignition switch to all lights and prolly the computer as well.