Fuel Pressure Test (Part 2)

[@marcoscott2146]

Solid video! This helped me figure out stuff on my 94 s10!

[@tarassmith2325]

again best yet, thorough and well done, of all the vids i have seen, most informative , clear , and i have learned a lot very many thanks for your good work.

[@RockysRoadshow]

Greetings...taras Smith.........Thanks for watching.........Well, (most of the time), I try to keep my explaining of things, in, a shall we say, simple way, which (I hope), will probably, make things, a bit easier, for people to understand, especially so, for the folks, that haven't seen this, or worked on, this type of stuff before..........I'm pretty much like everyone else out there, as in...I-Learn-as-I-go...so to speak.........I sure do appreciate your kind words, and.......till next time.......Be Safe, take care, and have a good one.

[@howardseward2838]

Fuel pressure specs on a 2002 Mercury sable

[@nanmer7135]

Why don't you put a link on the fuel tester gauge your using in your description?

[@RockysRoadshow]

Greetings...Armando Mermea.........Thanks for watching.........Well, I usually don't post links at all, because, it depends upon, where Ya might be living on Mother Earth...lol...........I bought this not-so-expensive one, at a Canadian Tire store, a few years back..........There are basically two types of fuel pressure testing gauges available, one being for, "low" fuel pressure, up to about 10 PSI (Pounds per Square Inch), and is used mostly for engines that have carburetors on them, and, can sometimes be combined with a Vacuum Gauge, that will probably be reading in Inches of Mercury (great for engine diagnosis, and also, indicating, that Ya might have a vacuum leak somewhere, possibly)..........The one that you see in this KZbin video of mine, is the "High Pressure" model, that is used mostly on fuel injected engines, that have fuel pressure, that is well "above" 10 PSI.........Make sure, to find the fuel pressure "Specification", for the exact engine and vehicle combination, that you are working on, in order to be accurate........Have a look-see on Amazon, or E-Bay, if you're having trouble finding one, at your local auto parts store.........Good luck, and......till next time......Be Safe, take care, and have a good one.

[@nanmer7135]

@@RockysRoadshow Yes, I'm well aware of which gauge does what. What I'm looking for is something of good quality. If you can't post a link atleast mention the brand it is if possible.

[@elboregojhb]

I replaced mine with a new one and nothing. It doesn't work. Turns over but it's not starting.

[@Barry11997]

I probably missed it but should it hold steady with the key off or just go down to 0 when i cut my off it drops

[@RockysRoadshow]

Greetings...barry cowan..........Thanks for watching.........If your engine/fuel injection system, looks just like this video's does, then, here's, what's going on, for Ya.........When you turn the ignition key, to the "run" (not "start") position, then, the electric fuel pump, that's inside of the gas tank, will run for about 2 or 3 seconds, to "prime" (pressurize) the fuel system, then, when you turn the ignition key, to the off position (to take the key out), the fuel pressure, should hold high and steady, for 5 minutes or more (you can also "re-prime", the fuel pump's pressure, by tuning the key on, first time, for a few seconds, then, turn it off, for, oh, about 10 to 20 seconds, then, turn the key, back to the run position, and, it should, re-prime fuel pressure, after, each, 10 to 20 second waiting period, while having the key, in the off position)...........If the fuel pressure drops really fast, then, there's usually a leak somewhere.........With the engine..."not running"...have a look, inside of your exhaust system's "tail pipe", near the rear bumper.........If the inside of the tail pipe, looks like it's all coated, with dry, black colored carbon, then, the engine, is probably running way too "rich" (too much gasoline, being burned), and sometimes, the "fuel pressure regulator", that's inside of that aluminum plenum (intake manifold), will..."spring-a-leak"...and, if so, then, the best thing to do, would be, to replace the entire fuel injection "spider" (as it's usually called), along with, what is called, a..."nut kit" (which is really, just, two, light colored, nylon/plastic, fuel lines), which might develop a crack, causing a leak, possibly.........I tried replacing, just the fuel pressure regulator, by itself, but, after a year or two, it sprung a major leak, and I needed a tow truck, to git-er-home...!!!...lol.........There is only..."one"...Big, fuel injector (maxi-injector), that is part of, the fuel injection body/spider, that might also (rarely), be leaking, possibly..........Also, there are 6, spring loaded poppet valves (part of that spider), that might have, a bit of a leak too, possibly..........Then, there is also a "check valve", that is part of, the electric fuel pump assembly as well, that won't hold pressure, if it's malfunctioning.........I've had it, where, if, it's just the fuel pump's check valve, that's not holding pressure, with the engine "not running", but, the engine starts and runs really good, then, I wasn't too concerned with the fuel pressure dropping, under this particular circumstance.........If there's, any kind of a fuel "leak", that's inside of the plenum (intake manifold assembly), then, get it..."fixed-right-away"...!!!...because, there are two, gasoline drain holes (one on each side), at the bottom of, the plenum/intake manifold, which will..."drain"...any "leaking gasoline", right into, one cylinder, on either bank (side) of the V-6 engine, and, if the engine..."gulps"...lots of liquid gasoline, into, one (or both) cylinders, while the engine is running reasonably fast, then, there is the possibility, of..."Hydro-locking"...one, or maybe two, of the engine's cylinders...!!!...can result in..."Major engine Damage"...!!!..........If you remove the..."Tuning Valve"...(looks like, it's made out of black plastic), that's, on the top/center, of the aluminum plenum (only held in, by, two screws, and, has a small wiring connector on it), then, once it's removed, just shine a flashlight, down, into the hole, and look for, any...puddles, or wet spots...of gasoline (on a mini-van, a small mirror, will usually help, quite a bit), and also, have a ...fire extinguisher...nearby, just in case, something weird happens, and.......till next time.......Be safe, take care, and have a good one.

[@Barry11997]

@@RockysRoadshow i agree with you ive looked inside from the piece that pulls out in the very top of the plenum. There was a clean spot by the regulator i even even primed it and seen fuel leak out. Probably just gonna bite the bullet like you said and just buy a whole unit. Any recommendations on a good unit. Ive bought i believe it was delphi mpfi for a 97 style its been kinda questionable

[@RockysRoadshow]

Greetings...barry cowan……….Well, it kinda looks like, I forgot to mention those, shall we say...clean-looking-gasoline-washed-areas...that, tend to be, a somewhat common occurance alright...…….Also, if that clean-gasoline-washed spot, occurs on the right/passenger side, on the inside, of the lower intake manifold/plenum, then, it'll probably be, that, the rubber-like diaphragm, that's on the inside of the fuel pressure regulator, has failed (crack, or, whatever?)...and...if the leak is found, to be, on the left/drivers side, then, it'll probably be, that, one, of the two, high (gasoline) pressure, white colored, nylon/plastic fuel lines (aka, the nut kit, as it's called sometimes), has become faulty/leaking (crack in it, or, whatever)………..I installed an "Autoline" (brand) fuel injection "spider" (as it's usually called), and, I think, that, it was a reman/remanufactured unit, that looked, just like brand new, when I took it out of its shipping box...!!!...and, it has also, held up/operated really good too...…….The two white looking, nylon fuel lines (aka, the nut kit), had the (brand name) "Standard", showing on it, and, has been good, so far...…...Seeing as how, I had it disassembled, down to this point, I also, removed the lower intake manifold/plenum, from the engine block, and installed, a pair of "intake manifold" gaskets, and, I'm glad that I did, because, the original/factory ones, sure looked, all dried up alright...…...I used "fel-pro" gaskets, but, I did notice, that, these particular gaskets, "didn't have" the "separator bar" (gasket divider), that is usually on/part of, the factory intake manifold gaskets, that partitions, the two separate intake ports, on the cylinder heads, that are close to each other/side by side, from each other (not sure why?).........After all, was said and done, then...."Wowsers"...!!!...what a difference...!!!...instant throttle response, seems that, less gas pedal is needed, to go any speed Ya want to, and, if the engine hasn't been running for about a week or so, then, just turn the ignition key, and it starts up right away (no waiting at all...lol)..........So yeah, consider installing, some new intake manifold (lower plenum) gaskets, while Ya have it apart, as far as Ya have, just in case, they aren't sealing, as good as they should be........Check out Rockauto.com, for information, about auto parts, because, once there, you'll be able to see the different brands, as well as, some pictures too, oh, and also, most of the parts that you see, will usually have a direct link, to the parts manufacturer's website..........Good luck, and.....till next time......Be Safe, take care, and have a good one.

[@62SHIVAS]

Tnx once more.... help me a lot :D

[@RockysRoadshow]

Greetings...Robert S - Norway..........Sorry, for not replying earlier, as, I must have missed your comment.........Well, better late, then never, I suppose........You're welcome, and, thanks for watching.........It's good to know, that, this video of mine, was able to help you out, and......till next time.......Be Safe, take care, and have a good one.

[@merrittmcdowell8675]

Boy 3 minutes worth of info in a 15 minute video lol

[@victorialouden1912]

Your going about air its a closed system get to the point.

[@RockysRoadshow]

Greetings...Victoria Louden............Thanks for watching...........Well, there is..."air" (actually, it's intake manifold or plenum "vacuum"), that will be involved, with certain types of fuel injection systems...............Let's take this fuel injection system, as an example, that you see in this KZbin video of mine, shall we...........There is a "fuel pressure regulator", that's (part of), mounted onto, the so called, fuel injection spider (unit), and, the engine's, intake/plenum vacuum signal (air pressure, if you will), affects, the spring loaded diaphragm, that's hiding, inside of, the fuel pressure regulator (unit)...........Yes-Sir-ee-Bob, there's even a small hole in the fuel pressure regulator's, metal housing/body, that, the engine's, (intake) plenum, vacuum (air pressure) signal, travels through, to cause an effect, as to, the position, that, the (internal) diaphragm, will be placed in, and that, my friend, will have an affect/change, as to, the amount of fuel pressure, that gets delivered to the fuel injectors, or, in this case, the 6-Poppet Nozzles, that are installed, into the engine's, lower intake manifold...........There are some specifications, that are out there, that will be sayin', that, the "fuel pressure", might drop, by, 3-to-10 P.S.I. (Pounds per Square Inch), due to, the amount of, plenum/vacuum signal, when, the engine, is just at idle speed RPM's (Revolutions per Minute), of the engine's crankshaft, that is...........So, let's now say, that, the vehicle's gas pedal, is pushed all the way down, then, the intake/plenum vacuum signal, will probably drop down, to almost nothing/almost Zero Hg (Hg = inches of mercury, as seen, on, the good ole, mechanic's, engine vacuum gauge), then, the fuel pressure regulator's internal diaphragm, will now be at a position, where-by, the fuel (gasoline), will now, be able to flow, without the amount of (fuel pressure) restriction, that it had, when the engine, was at, idle speed RPM's............So then, an idling, (stock/factory) engine, will usually produce, lots of intake manifold/plenum vacuum (signal), and, an engine, that's going, pedal-to-the-metal, and under hard/extreme acceleration, won't have very much/if any, intake/plenum vacuum signal at all............There are, some externally mounted fuel pressure "regulators", that kinda, look like, a small can/canister, that have, a small metal pipe, sticking out of it, that will have a rubber hose, pressed onto it, and, the other end of this rubber hose, will probably be pressed onto a fitting, that, might be, screw-threaded into, the engine's, intake manifold or (intake) plenum, in order to transmit, that there, intake manifold (or plenum), "vacuum signal", directly to, that diaphragm, that's, hiding inside of, that particular type of, fuel pressure regulator............Engine "vacuum", is basically, just, any amount of air pressure, that is "lower than", what, the Earth's, natural air pressure, happens to be, on the "outside" of the engine, at that very moment in time, and also, the Earth's air pressure, will be getting lower, the higher, that you go, up, in elevation, as in, higher up, on, one of Mother Earth's, very high "mountain peaks", as an example...........If you are having, any engine, fuel pressure delivery problems, or other-wise, then, just let me know, about, the vehicle's...Year...Make...Model...Engine size...etc....and I'll see, what I can do, to help you out, and........till next time........Be Safe, take care, and have a good one.