Hi guys
I'm hoping someone can shed some light on a recent fuel problem i've been having with my 3.5 v6 Jack.
Some back ground...
3.5l V6 on gas.
Vehicle developed a starting issue about a month ago, took it to gas tuner who said it was running super rich and leaned the gas out, it made a slight improvement but he suggested it may be an injector leaking issue and to run it for a few days to see how it goes.
Since then it has had an idle issue where the revs raise and fall upon start up.
Vehicle developed a strong stale fuel smell about a week ago so on Friday night I drained the fuel tank and refilled it with new fresh fuel.
Stale smell was gone, but replaced with a strong fresh fuel smell.
I thought perhaps a breather hose had come adrift underneath. During my inspection I discovered the smell was coming from under the bonnet.
After hunting around for the culprit I discovered fuel pouring down the back of the engine and traced it to the fuel pressure regulator.
It appeared to be coming out of a small port on the top of it.
I noticed that the rubber hose which should attach to it had come adrift and was split, so I nipped off the split section and reattached it thinking it was the fuel return hose and was the problem.
Nope, upon star tup it began to miss and run like a dog however the fuel smell and leak had stopped.
After a minutes thought I realised that the hose I reconnected was in fact the vacuum hose and as the fuel was no longer running down the regulator it was obviously being sucked straight into the engine through the vacuum hose causing the rough idle etc.
I removed the hose and plugged it off, put a rubber cap over the fuel pressure regulator vacuum port and restarted it.
It still has a slight miss, but it started and ran as it had prior to reconnecting the vacuum hose.
Some fuel began weeping out from under the rubber cap I put on the regulator port
So I have come to the conclusion that the fuel pressure regulator is stuffed and needs replacing, the problem is, how do you do it, as far as I can tell the regulator is part of the fuel rail and cant be separated by a home mechanic.
Any ideas would be greatly appreciated.
BJ