Fuel pressure regulator missing

[Firebirdgm2000]

04 Yukon.... Repairing a misfire and low and behold my fuel pressure regulator is completely missing... Please help

 

[Firebirdgm2000]

I'm wondering where this thing is on the LM7 all help is appreciated.

 

[M1Gunner]

I'm wondering where this thing is on the LM7 all help is appreciated.

I believe on that platform it is a component contained in the fuel sender assembly.

 

[Firebirdgm2000]

I will be dropping the tank this weekend to find a fuel smell and leak so hopefully it's sitting somewhere in there. Unfortunately there is no information I have come across to support this, the only pictures I find are the ones they show it on the fuel rail.

 

[M1Gunner]

I will be dropping the tank this weekend to find a fuel smell and leak so hopefully it's sitting somewhere in there. Unfortunately there is no information I have come across to support this, the only pictures I find are the ones they show it on the fuel rail.

What all information have you gathered about the fuel smell concern? Have you checked the fuel rail and injector o-rings for any leaks/spray for example?

And what was causing your misfire?

 

[Firebirdgm2000]

What all information have you gathered about the fuel smell concern? Have you checked the fuel rail and injector o-rings for any leaks/spray for example?

And what was causing your misfire?

Everything near the engine is pristine. Using my snap on scanner the random cylinder misfire would have been caused by the pressure regulator. I cleared the codes two days ago and it hasn't returned, only comes on when it's cold outside and it's been warm for the past week. I do have a new vapor canister and a new fuel pump should be here by Thursday. The tank is wet but not dripping so at this point I won't know until I drop that tank.

 

[M1Gunner]

Everything near the engine is pristine. Using my snap on scanner the random cylinder misfire would have been caused by the pressure regulator. I cleared the codes two days ago and it hasn't returned, only comes on when it's cold outside and it's been warm for the past week. I do have a new vapor canister and a new fuel pump should be here by Thursday. The tank is wet but not dripping so at this point I won't know until I drop that tank.

Sounds like the o-ring that seals the fuel sender assembly my be the culprit here causing that smell of raw fuel.

As for the p0300 that could be caused by anything from a faulty camshaft sensor to an annoying vacuum leak.

Have you checked the fuel pressure and injector pulse?

 

[Firebirdgm2000]

Sounds like the o-ring that seals the fuel sender assembly my be the culprit here causing that smell of raw fuel.

As for the p0300 that could be caused by anything from a faulty camshaft sensor to an annoying vacuum leak.

Have you checked the fuel pressure and injector pulse?

I have not checked either, how would I go about doing this should I use the scope for pulse or is it raw data I can view realtime?

 

[M1Gunner]

I have not checked either, how would I go about doing this should I use the scope for pulse or is it raw data I can view realtime?

You have to use a fuel pressure gauge and tap into fuel rail via the service port. Compare the manufacture specifications to your readings with key on engine off and key on engine running. If that's good then there's no reason to change out the pump assembly and you move on to check injector pulse.

As for injector pulse you'll have to disable the fuel system (pulling the fuse for the fuel pump or its relay then start it and let it die) one by one disconnect an injector and plug a noid lite into the harness connector then crank it over and watch for it to blink.