fuel pressure problems

[shackwrrr]

well my stock FPR was stuck giving me alot of pressure. Well I didnt have the money for it and I like to mess around with stuff and do it different. I got an adjustable fuel pressure regulator. well I have a problem Ive tried 2 different gauges and both of them say that it likes to run in the 55-60 psi range. If I set it at the stock 35 at idle and 40 with the vac line unplugged it just misses like crazy. I cant get why this thing wants so much fuel pressure.

Jerry I still have that code 53 and my purge solenoid still ticks at around 1500 rpm. It sounds like its duty cycle controled. It starts out off at idle and then slowly ramps up on time untill its at 100%.

I cant figure the fuel pressure problem though

[jtgh]

your ECU is bad.
dont know way. but is bad,
EVAP must never click at idle (repeats) a sign of ECU rebooting over and over.
ECU is crashing, and then detects this crash (called watch dog timer) and then reboots its self. DOOM.

53 is bad ecu all manuals say that in plane text.

your pressure reg is no good, it dont have a vacuum regulator on it.

that reg. of yours is for custom RACING ECU ones that are programmed for your exact setup.
you ECU will never ever like that regulator. Racers us a BARO sensor attached to the ECU that compensates for dumb FPReg. a whole diff. ball of wax.

you do know it (OEM) regulates for altitude , right , and now your ECU has no idea what altitude you are at. (ECU trusts it, if you lie to it , you get GiGO)
Garbage in results in Garbage out. All puters.

you can get one of this for almost nothing an a wrecker. what $5

come on, your lil kick will love you for it.

cheers.

[shackwrrr]

this regulator does have a vac line on it linear rate I remove the line and it raises around 5-6 psi.

idle specs are
29.8-37psi
Engine off key on specs
35.6-42.7

so stock the computer expecs a change in about 5-6 psi to happen between full load and idle. My regulator can do that. If I set it at idle to around 35 psi then pinch the vac line it goes up to around 40-41 so it is well within spec. I just dont know why it wont run there. It runs absolutely awsome at 55-60 psi but thats where its not supposed to be.

That solenoid doesent click at idle. It just happens to be noisey no problem there.

well anyway I just nabbed an ecu off ebay for 60 bucks that matches my numbers exact so I will see about this code 53 thing

[jtgh]

me dumb. i finally figured out what you are doing.

both of them say that it likes to run in the 55-60 psi range

rephrase: My engine only runs right when I raise my fuel pressure to 55psi.?

your car runs lean( first order problem) and you raise fuel pressure and car like it.
DIG DING, you are first to win the "First time anyone EVER posted that award"
Is it only lean cold , HOT or both?

wow.
may i suggest , you put the pressure at spec. and leave it and fix the broken EFI.
The pressure is a predicate, it must be at spec or all else is just junk. ALL.

16V:
1: bad MAF
2: air leaks. (any leaks that dont pass thru the MAF is illegal and very bad)
3: Injectors clogged . (have them cleaned for $18 each)
4: slight lean hot, O2 sensor bad or exhaust has a crack near O2. causing O2 sensor to be covered in carbon blanket ( cyclical it can be , Rich Lean, Rich , Lean , crazy)
5: EGR stuck open , making motor seem lean . but not. (loss of power and idle)

im sure i missed something.

sorry im so slow and bad and understanding you. Im on track now.... huh?

cheers.

PS:
Ok, , you never told me what aftermarket reg. you had, (some even have turbo ramps(amps) ,etc, many there are .)



16v data

1.6L KEYON-nostart ----35.6–42.7 psi Static test:
1.6L Keyoff , min. 28.4 psi for one minute. (leak down spec) , Residual pressure test.
1.6L KeyON-start --- 29.8–37.0 psi , Running pressure. <<<< CRUCIAL TEST.

[jtgh]

great nab price $$ on ECU. tops.

that reg should work, the one on car now. if it reacts in the correct way for vacumm , it is good.

the key here , that the pressure differential across the injector must be never changing.
This allows the ecu to inject at any alititude , in the exact same way (1 equation)
this is how it really works, and above comment, is impossible to test.
but the pressure drop test will show the start and end points.
it looks ok.

[shackwrrr]

Ill wait to drop the psi back to spec I need the transportation right now.

when I lower the psi it lean misfires like crazy from idle all the way up.

I will get that ecu and see what happens. I can acually clean the injectors for free by myself I just have to be not lazy and take them out. My school has an injector test/claning bench with ultrasonic cleaner.

[jtgh]

cool , access to the bench cleaner.

if pressure is correct.
1: bad injectors.
2: ECU bad (not lean)
3: bad input to ECU. MAF. Unplug the maf , keep a hot foot for proper idle and see if it makes full power. (electrical unplug it) Mimic mode is crude but can tell you ,bad maf.
4:air leaks.