87 f250 302 EFI shouldnt the engine quit if you remove vacuum to the fuel regulator? Im also getting the strangest noise when turning off the engine. its like a suction noise that last for about a half a second. and also a whisle noise at Idle trying to get the bugs worked out please help with any ideas.

 

No but the fuel pressure will jump from about 32 psi to about 42 psi at the injectors (fuel manifold).
May be the A/C system bleeding down.
Vacuum leak??
Any codes?

 

no codes, and I havent been using the ac i dont think it works

 

it may just be the air intake making that noise. I have a custom intake in my 88 f150 which the air flow is about 12". When I shut my truck off, and turn the key on(not running) you can hear excess air going into the engine. I also get a fairly loud sucking noise becuase of the short intake. Basically the same sound if you were running just the throttle body, no hoses.

I would check all your vacuum hoses. Dont mark my words, but I belive on my 88 there is...from the vacuum tree.. One going to the brake booster, One goes to a canister by the passanger headlight, the set of three goes to a canister on the passanger fenderwell and to the computer. Another to the Y on the drivers fenderwell. Also, theres cheap vacuum lines that come from the computer to the smog pump, fuel pressure regulator and somewhere else I cant remember off the top of my head. I would really check those lines. I belive one is pink(or red), yellow and black. They go around the back of the engine then near the exhaust manifolds which make them very brittle. I tried taping it together but broke it again. Go to an auto store and just buy a couple yards of vaccum hose and replace them. Also, there is two vacuum lines on the throttle body.

If you havent seafoamed the truck, I would do that first.

 

this is probably dumb. but, what is seafoam and what does it do?

 

The sucking noise is probably normal, and if it is the same noise as I hear on my truck, it is likely coming from the PCV valve. I have a loud whistle just above idle, which I have attributed to the IAC ports somehow or another (there is a thin plate in between the IAC and the throttle with air passages and bleed screws that I think is the root of the whistle).

 

Im getting about 17hg off the manifold witch i believe is good. but the noise thats coming out of it when I shut it off doesnt make sence its a loud suction noise that was never there before. Im wondering if its something i did wrong when I swapped the engines. I cant find any leaks and there all new lines I changed out all the brittle crap that ford uses for vacuum lines.

 

conanski HELP!!!

 

How does the motor run besides the strange noises?

 

I have also heard the compression bleed off past the rings or valves after the engine is shut off. Also some engines will turn backwards some after they stop and you will hear a sound as it is turning backwards.

A bad break booster will make a leaking sound if there is a hole in its diaphragm.

 

It runs good but its running rich and I believe its starting to foul plugs. because I noticed a few times yesterday it had a miss on excelleration.

 

yeah maybe this new motor is cranking out more vacuum than the old engine and it has torn the diaphramg on the booster? I dont know.

 

A whistling noise could be anything, a slight port mismatch between the upper and lower or a gasket hanging out into the port opening.. it may have no affect on performance and just be annoying.
The suction noise could just be the vacuum resovoir emptying once the motor is shut down.

The 5.0 I just put in also has an issue on cold start, it doesn't idle very well, stumbles on throttle tip in and makes some whistling noises on occasion. I suspect a vacuum leak somewhere outside the motor because the 5.8 was exhibiting a similar problem before it came out. So I'm gonna try to isolate the vacuum resovoir, brake booster, and cruise control systems 1 at a time to see if I can find the source of the problem.

 

what plugs are you running? I just swapped out expensive AutoLite Platinums for the cheapo Coppers and its a world of difference, and I only had the platinums in for two weeks....they are junk. It would bog and then I would all of a sudden get full power. I have read a lot of people who have deep pockets still use the autolite coppers. Also, redo the wires, cap, rotor and maybe coil.

Where is your timing set at?


Seafoam is a can that is dumped into the brake booster vacuum hose which will burn out all the gunk and other crap that may be in there. Basically pour it in, let it sit for 5-10 minutes and drive it. She'll smoke A LOT, which will be all that crap burning off.

 

I found that the pcv was disconnnected. and sucking air. I changed plugs and wires, cap and rotor and it fixed every thing except. when I started it up this morning while idling it kept trying to run out of gas or somthing at least thats what it sounded like. once it warmed up it was fine. what would cause this... I still think my fuel regulator is taking a crap.