Found problem during tune up/ no vacuum to FPR.

[gvr4ever]

I was bored today and I couldn't remember the last time I changed my spark plugs, so I thought why not.

At the same time, I thought I would just double check everything. Timing, base fuel pressure.

Anyway, I'm not getting any vacuum to the fuel regulator!!!! I know I had this about a month ago.

Anyway, boost gauge shows exactly 18" Hg, so I know the engine has vacuum. Anyone know where the hose goes, so I can try and replace it or something.

Thanks

 

[jepherz]

Where what hose goes? Did you remove the solenoid for hot starts? There is a nipple on the stock intake manifold, a few inches to the passenger side of the FPR that it normally goes to.

 

[gvr4ever]

I haven't changed anything. I've been reading up on that solenoid, don't know how it works yet. I checked back later and I had vacuum again.

So, what is the car suppose to do for hot starts, stock.

 

that valve just closes on hot starts which raises the presure so the gas that has been cooking in the rail gets moved out quickly for new cooler fuel which makes easier to start when hot. I took mine out when i put the aeromotive fpr in, but in warmer climates im sure it helps on those 100+ days doing a hot start.

 

The FPR solenoid should deactivate 2-3 minutes after a hot start, so you won't see vacuum at first if the engine is hot.

 

[gvr4ever]

Doh, well I waited, but I guess not long enough. I didn't realize it could take 3 min to work right. I guess everything is alright.

That higher fuel pressure makes for some rough hot starts.

 

[GVR4_1057]

You can bypass it which I think most people do. Run it right from the intake manifold to the FPR. It is only a 4 or 5 inch long hose. Cleans up the underhood too /ubbthreads/images/graemlins/smile.gif