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kevsha
09-02-2008, 02:58 PM
Ok, so i got my SC back to gether. i installed a new adjustable fuel pressure regulator. my question is what kind of fuel pressure do i want to see. basically all i have done is a 10% pulley, screamin deamon coil pack and live wires and a k/n cone filter, and a magnuson rebuilt blower.

i have like 33-34 at idle and like 38-40 when i rev it up. i havent really been able to roadtest it as i just now got back from my insurance agent and put it back onto my policy.

grey500se
09-02-2008, 03:16 PM
pretty sure Ford's are 39psi relative, so at idle its usually around 20 inches, or about -10psi, so idle pressure will be 39+ (-10) = 29psi, get it?

With a better blower and OD pulley it will probably flow a bit better so your number's sound about right.

rzimmerl
09-02-2008, 03:19 PM
You need to set your base pressure at 39psi with the car running and the vac line off the regulator. Do you have a wideband o2 sensor? You really shouldn't need to adjust for those mods.

Boostedbird07
09-02-2008, 10:49 PM
My fuel pressure is between 30 and 35 at idle and goes straight up to 50 when you rev the engine. I was just wondering if that was good or not.

mywhite89
09-03-2008, 07:22 AM
Hook a fuel pressure gauge up to the car. turn the key halfway and jump the fuel pressure relay so the pump runs continuously with the key turned halfway and the engine off. You can jump the relay from actual relay in the trunk or from the eec-iv test port on the passenger side of you engine bay in front of the firewall. Pressure should stay at 39psi, if not you need to set it at that. If you set it with the engine off, you don't need to remove the vaccum line. This is the easiest way I know.

btw, if you are able to check you fuel pressure while driving you'll need to pay close attenetion to your boost gauge. Drive the car and give it just enough throttle to hold 0 vaccum and 0 boost on your gauge. At this point the car should make 39psi fuel pressure.
Chris

kevsha
09-03-2008, 10:06 AM
Thanks everyone. i have it set to 39 PSI vac line off engine running... i haven't really been able to test it under load, or with boost as it seems as if the motor "breaks apart" as soon as you give it more than 1/4 throttle.... it has at least one dead miss and i can't figure out why... it seems like maybe and ignition problem....i don't know. it will run smooth when reving it up at idle, its just when i take it on the road that the problem is evident. i thought it wight be my incorrect fuel pressure... but the problem persists

rzimmerl
09-03-2008, 10:31 AM
its not your fuel pressure causing the problem, its called detonation. You intake temps are too high with the 10% pulley, unless you have upgraded the IC or added fan I recommend you do it now. At least drop your plugs down a heat range or two, an Autolite 764 or 103.

kevsha
09-03-2008, 01:35 PM
its not your fuel pressure causing the problem, its called detonation. You intake temps are too high with the 10% pulley, unless you have upgraded the IC or added fan I recommend you do it now. At least drop your plugs down a heat range or two, an Autolite 764 or 103.

intake temps too high at 1/4 throttle or less? i'm not even hitting 1lb of boost before it starts to fall apart and barely any load/RPM. i have dealt with detonation before but with high load, rpm, and boost.... i mean i'm shooting in the dark here and it definatly seems like an ignition problem... i installed the plugs from SCP:

http://supercoupeperformance.com/partBrowser.aspx?partId=80

and gapped them to +-.060" per instructions on this page

http://supercoupeperformance.com/partBrowser.aspx?partId=510

idk, i'm probably going to pull the plugs and look at them and maybe see about going a step cooler like you said...

rzimmerl
09-03-2008, 01:59 PM
are you running the Screamin Demon coil? There have been many reported issues with them.

kevsha
09-03-2008, 02:09 PM
are you running the Screamin Demon coil? There have been many reported issues with them.

well, i took it off a friend of mine's SC before he sold it.... he never had any problems with it, then again he ran stock wires and never changes the gap.... i wish i had my old coil pack to swap in....

Motohead
09-03-2008, 02:14 PM
Thanks everyone. i have it set to 39 PSI vac line off engine running... i haven't really been able to test it under load, or with boost as it seems as if the motor "breaks apart" as soon as you give it more than 1/4 throttle.... it has at least one dead miss and i can't figure out why... it seems like maybe and ignition problem....i don't know. it will run smooth when reving it up at idle, its just when i take it on the road that the problem is evident. i thought it wight be my incorrect fuel pressure... but the problem persists

I had that problem once it turned out to be a couple of spark plug wires switched. It ideled fine but under any load missed bad double check your spark plug wireing also I remember one of the manuals having the wrong diagram make sure you get a accurate diagram

kevsha
09-03-2008, 02:19 PM
I remember one of the manuals having the wrong diagram make sure you get a accurate diagram

it wasn't wrong on the ford manual was it.... because thats what i went off of, the ford 1990 workshop manual....that would suck it it was incorrect though it wouldn't supprise me... anyone have a pic of the coil and the firing order?

David Neibert
09-03-2008, 04:39 PM
it wasn't wrong on the ford manual was it.... because thats what i went off of, the ford 1990 workshop manual....that would suck it it was incorrect though it wouldn't supprise me... anyone have a pic of the coil and the firing order?


http://members.tccoa.com/dneibert/PlugandWireLayout.jpg


David

kevsha
09-03-2008, 05:25 PM
http://members.tccoa.com/dneibert/PlugandWireLayout.jpg




thanks, yea i think thats what my ford manual says too... i'll double check when i get home from work. i have another set of wires to try and swap in.. i know the cyl 5 boot is ripped. i tried to correct it with electrical tape but its possible that wan't good enough, though i don't hear it arching anymore

kevsha
09-04-2008, 12:35 PM
got it figured out, cyl 5 plug wire boot was torn... put some shrink tubing around it and seems to be keeping it unsulated pretty well... figures, ii spend 110$ on these damn wites and i end up tearing a boot putting them on.... my luck

neverfastenough
09-04-2008, 12:38 PM
FYI, you can still get OEM motorcraft wires for around 60bux from the dealership.

Corey

kevsha
09-04-2008, 01:04 PM
FYI, you can still get OEM motorcraft wires for around 60bux from the dealership.

Corey

indeed you can, and i can get them even cheaper as i used to me a mechnic at the delaer near me and they still give parts to me at cost. but i was going with an upgrade since i upgraded the coil.... and then i ripped the boot

MagpoweredSC
09-04-2008, 01:22 PM
I think a gap of .060 is way too much for a supercharged car, I would gap them closer to prevent spark blow out. Maybe someone else can chime in on this also, I forget the gap but I thought it should be like .045.


Mark

Bacondoggy
09-04-2008, 01:36 PM
where did you get your fuel pressure regulator from? Why did you go with an adjustable one? I think mine may be going out, but not sure - I would like to have an idea where to get a FPR if I need one though, and what people recommend is best suited for our cars...

kevsha
09-04-2008, 03:36 PM
where did you get your fuel pressure regulator from? Why did you go with an adjustable one? I think mine may be going out, but not sure - I would like to have an idea where to get a FPR if I need one though, and what people recommend is best suited for our cars...

i needed a new one, and a friend of mine had bought a lot of like 10 of them for his Turbo Coupe because he found them cheap on e-bay and the early regulators are the same as on a fox body. so i used it because he gave it to me rather than purchacing a new one... its an Accel regulator. SCP sells adjustable regulators too...

3 hole http://supercoupeperformance.com/partBrowser.aspx?partId=118

2 hole http://supercoupeperformance.com/partBrowser.aspx?partId=119


I think a gap of .060 is way too much for a supercharged car, I would gap them closer to prevent spark blow out. Maybe someone else can chime in on this also, I forget the gap but I thought it should be like .045. ...

you are correct, that is alot... HOWEVER if you click on the link i put up the the Screamin deamon coil pack that i got from SCP it is recomended to open the gap up due to the fact that the new pack generates a stronger spark i gapped them to the bottom of the scale given on the page. and since i trust that Bill at SCP has a substantial amout more knowlage about these cars than me, i used his recomendation


The Screamin' Demon Coil is designed to produce a longer duration spark and allow plug gaps to be opened up to an astounding .060" - .065".

taken from

http://supercoupeperformance.com/partBrowser.aspx?partId=510

Bacondoggy
09-04-2008, 03:51 PM
does he have any more of the regulators? How did you know you needed a new one? did you have a check engine light? What were the symptopms of the car.how did you know it was bad (I'm trying to figure out if I need one as well)

None2Slow
09-04-2008, 04:17 PM
does he have any more of the regulators? How did you know you needed a new one? did you have a check engine light? What were the symptopms of the car.how did you know it was bad (I'm trying to figure out if I need one as well)

If you pull the vac hose off the regulator and it smells of fuel, that's 1 way. If you put a fuel gauge on and it wont hold or build pressure, that would be another.
When my SC would sputter with any kind of boost, it turned out to be a combination of a bad plug wire and the short hose from the fuel pump to pick up tube in the tank was split.

kevsha
09-04-2008, 04:41 PM
If you pull the vac hose off the regulator and it smells of fuel, that's 1 way. If you put a fuel gauge on and it wont hold or build pressure, that would be another.
.

yea, mine would take a while to build pressure when trying to start, and it wouldn't hold fuel pressure after turning the car off. but seeing as i had the fuel rail off, i was going to replace it anyway.

what kind of symptoms are you having...uhh... bacondoggy...

Bacondoggy
09-04-2008, 05:42 PM
I dont even know where to begin. My car has way too many issues. It has a strong gas smell when the tank is like 1/2 full or more. It seems to overheat after driving for 10-15 minutes, then a check engine light comes on. The code is for the driver's side running lean. What I did fix:
New O2 sensors, TB, MAF cleaned, TPS, IAC, PCV, fule filter, plugs (yes they are on correct), car has 70k, engine has maybe 5-6k with bored over.030 I am sure I am missing everything I replaced, but almost POSITIVE there are no vac leaks. 10% od pulley. new temp sensor. fan works (both speeds). Exhaust currently is mustang v6 headers into catless no resonator and a single glasspack @ the end. I have worked on this car SO much and threw SO MUCH money at it, and it seems to never get to where it is "ok" I had to take it to the local dealer to figure out the computer was shorted out, I paid for a new one, and he put it in, put a new o2 sensor in (I could have done those both in minutes), and charged me like $800 for it. At least the car is not in total limp mode, but I am so frustrated and pissed I am at an end. Whenever I even think about the car I get irritated. I wish I knew of a knowledgable person here in York, PA.


Lol - name's Mark by the way ;)

kevsha
09-05-2008, 10:05 AM
well mark.... if i lived close to york i would come over to check it out, i'm pobably like a 2 hour drive away, right over the river in jersey.

you said your car over heats. what kind of thermostat do you have? does your fan come on at the right temp, did you ever replace the water pump? how is the radiator, is it clean... if you live in a dusty area it can effect it... when i first moved into the house i am in, my development was uner construction and the road was really disty, after a while my car would just start to run hot... washer the rad down, then all good...

all i can say is check, check, and double check. it onlt took a 1mm wide tear in my spark plug boot to make my car run like crap and make me think that i screwed it up...you may yet have a vacuum leak since you have a lean code, or maybe a bad injector does your car make 20" or more ov vacuum when you are coasting with your foot of the gas

the gas smell is probably a bad filler neck or something, i would say drop the tank and look for a leak

Bacondoggy
09-05-2008, 11:29 AM
the water pump looked good when I rebuilt the engine about 5k ago. I don't know if there are underdrive pulleys on the car or not though... Its not really dusty here, but I will clean out the rad. The fluids were just changed, I made sure there was enough and no air in the system. I changed the t-stat back to stock (I used a superstant) about 1k ago. I checked everywhere for a vac. leak - I dunno! I guess I can take the fuel rail out, and get the injectors tested... replace the FPR while I am at it... I will have to look where the vac guage sits next time I drive it... I know the fan comes on, I assume it does when its supposed to, when its hot and I look under the hood, its running. I also replaced the coolant temp sensor just to be safe...