colie1220

I was driving down the road in my 97 tahoe (4 dr vortec) and the truck suddenly had an extreme lack of power so I pulled over and it just died. Came to the conclusion it was the fuel pump and had it towed. Put in brand new fuel pump and it is still not kicking on. Checked all fuses and relays and found that the ECM II fuse had blown. Asked around and I got 2 answers, its a power issue to the pump replace wiring harness or the computer shorted out. Anyone have any ideas or comments please let me know THANKS!

colie1220

Changed the wiring harness and there is still no power, followed all the lines back none of them are pinched Please help I am lost and don't know where to go from here

colie1220

Since no one wants to help and/or has the knowledge to help me I am going to update in the hopes that this will help someone else. Discovered that the ECM I fuse was blown, replaced it blew again so there has gotta be a short or pinched wire some where. We followed wires from fuse box (under the hood) and found that the thinner pink wire from the ECM I FUSE was discolored to an orangish color and we r going to assume this is y the fuse kept blowing. Haven't gotten far enough to find out exactly where this wire leads to or to find out exactly how much of the wire is like this. Expecting snow, so this will delay working on the tahoe....will update soon......any and all comments are welcome. thanks

cleveland63b

are you sure there isn't power to the pump or just assuming? new doesn't always mean good

shamrock246

ECM B fuse is for the the fuel pump,ECM 1 powers the injectors and ignition control modual i see an ENG 1 but no ENG 2 fuse ENG 1 fuse powers the sensors and valves etc your going to have start chasing the short down on what ever leg is blowing the fuse do you have a good multimeter,theres a small black connector next to the fuse box in the engine compartment if you put that to 12v the pump should run all the time

colie1220

We checked the new wiring harness and there is no power coming from the power wire. We "jumped" the fuel pump and it did kick on.

colie1220

We do not have a multimeter but I did chase the wires and found that the thinner of the 2 pink wires coming from the ECM I fuse was burnt where it runs under the intake. There is a black connector that 3 go into it (coming from fuse box) and one comes out (going towards fire wall on pass side) the single wire coming out is burnt and an orange color. Do you know if the black piece is resistor or an inline fuse? I ran out of sunlight so I did not have time to chase the wire all the way to find out exactly where it goes. It seems it may go to the coil.

shamrock246

Those pink wires come off that fuse to power the injectors im not aware of any in line fuses could you get a picture of that black connector if you google the fuel pump circuit you should be able to find a drawing basicly the pump is cycled by the relay for a second or two to get the engine started then the oil pressure switch takes over and thats where the pump gets its power,dont have my manual in front me so not sure what the orange wire is powering

colie1220

So we continued to chase the burnt pink wire and discovered SEVERAL other burnt wires....thinking I am going to just replace the entire engine harness found one on ebay for 150 + 20 for shipping.....hoping and praying this will fix it.....I bought the truck for 1800 drove it for 2 weeks and it died. Once I buy the harness I will have put nearly 700 into it...I love my Tahoe and have head several people offer to buy it off me but I really do not want to part with it....Praying this is it

73shark

Try to find out why the wires are burnt or you may be just repeating history.