fuel presure regulator

[88"s/c lil"bastard]

has anyone used an adjustable fuel pressure regulator
on a stock agze with minimal mods air filter exhaust etc.

i have an 88 s/c and i have filter, exhaust, removed the a/c compressor, and i smoothed the intake ports on the intake manifold nothing major just removed some material for better flow i am wondering if i can expect better performance by maybe raising the fuel pressure a lil,,

[Papo J]

The stock fuel system runs rich at anything passed 3/4 throttle as it is, you will gain nothing with an adjustable FPR or by raising the pressure. If you get a larger pully then maybe but for the mods you listed you don't need to add any more fuel.

[88"s/c lil"bastard]

so y the hell does this thing bogg down?, its something fierce at first i thought it was my axle caue of hoe ruff the feeling was, is it the cv shaft? this automatic has been testing my patience , it likes to bogg on hills mostly but on flats too if im slow down enough,.. down shifting is never a problem but normal driving sucks!

[Papo J]

It doesn't sound like a fuel issue to me. Have you checked for vacuum leaks and made sure the timing was correct? Did you plug the AC idle up valve and vacuum hoses associated with it?

[88"s/c lil"bastard]

is that in the driver side next to the battery?

[Papo J]

Yes, the thing with the white nylon knob between the strut tower and the battery.

[88"s/c lil"bastard]

what should i do with those? jus plug both of 'em or run one hose into each nipple?

[Papo J]

You should plug both ends, running one into the other is going to increase the idle speed.

[88"s/c lil"bastard]

yea well im not sure it solved it but i think its a good idea to keep some of the engines natural vacuum i suppose you could get leaks through the ac idle up valves

[mr2tim]

Sometimes the fuel will flow to the back of the tank on a hill under power and the fuel pickup will suck air and stagger the engine. If you have more than a half tank of fuel this condition may not occur...

Just a passing thought on that hill "bog" condition..

[Papo J]

The fuel tank has baffles to prevent that from happening, I really doubt that's his problem.

[88"s/c lil"bastard]

i doubt its detonation cause i saw no sign in the spark plugs it could very well be the timing the car used to backfire too but doesn't anymore, it usually happens 2000rpm's especially when i slow down and what really surprised me is recently it happened coming off a ramp i never suspected it would again slowing down to yield back on gas and a ruff stumble, consistant on hills though but i think its more engine speed torque orientated issue,
could i have an issue with fuel, during the winter had serious issues starting cold. three hours fine 8 hours or overnight it was hell starting. i wanted to change the fuel pressure regulator but thats a 90$ part

fuel filter helped, sometimes it doesn't exactly start as quickly as i like, but its not a problem, having a full tank doesn't do thats not it,
i havn't been able to check ignition timing.

my plans are to change the timing belt asap! 80'000 miles and the car sat for 5 yrs




the car does everything else great and has good power up hills even before poweband

[mr2tim]

Ok how about the filter attached to the fuel pump, can you confirm it's not mushy with rusty slime deposits?

Originally Posted by 88"s/c lil"bastard

i doubt its detonation cause i saw no sign in the spark plugs it could very well be the timing the car used to backfire too but doesn't anymore, it usually happens 2000rpm's especially when i slow down and what really surprised me is recently it happened coming off a ramp i never suspected it would again slowing down to yield back on gas and a ruff stumble, consistant on hills though but i think its more engine speed torque orientated issue,
could i have an issue with fuel, during the winter had serious issues starting cold. three hours fine 8 hours or overnight it was hell starting. i wanted to change the fuel pressure regulator but thats a 90$ part

fuel filter helped, sometimes it doesn't exactly start as quickly as i like, but its not a problem, having a full tank doesn't do thats not it,
i havn't been able to check ignition timing.

my plans are to change the timing belt asap! 80'000 miles and the car sat for 5 yrs




the car does everything else great and has good power up hills even before poweband

[88"s/c lil"bastard]

yes i can, the car sat for five years it needed a new fuel pump, that is new.
this was done in my buddy's shop i let him get the fuel pump i don't think he cheaped out and got a uni fit i checked the prices online it was an expensive part, the one used was an exact match physically we both did the pump i payed top dollar for that pump i would hope he didn't throw a cheap aftermarket universal fit, i wouldn't know maybe there ok but i did consider the fuel pump wasn't doing its job, but doubtful,.

[HoLun]

so exactly what is wrong with your car? bogging can be caused by many things, too rich, too lean and ignition timing are main factors, and then theres the electronics side of problem that can cause bogging.

like what were you doing when its bogging? ie. accelerating hard? cornering? can you repeat the same result every time? engine at operating temp? ignition timing at idle? compression readings? all these information are important.

[88"s/c lil"bastard]

it seems it does it alil shifting at times i don't have any codes so i dont think its lean, unless im mistaken , i haven't gotten a compression test, so maybe i should.
im gonna flip if i don't fix it, i thought it was lean, gotta check timing but it loves to bog on hills, but that could be related to the turn involved in most of my trouble spots slowing down and shifting low revs light on the pedal, also triggers this but its not as bad even nearly as the harsh feeling from the engine that ive' experienced, which had me thinking it was detonation. mind you this car is an automatic previously mentioned.

[328FTW]

Bogging between gears is normally an over rich mixture, it was what mine did when the mix was too rich, forgot what caused it though. Must of been stupid if I can't remember.

Get a compression test to see if that is what it is because that can cause intermittent bogging..

[mr2tim]

If this car sat for 5 years and the fuel wasn't dumped out and the tank flushed?, that's a death wish.

You may have gotten a good pump and attached a new filter but, if you put it back into a dirty slimy tank the new filter will get clogged immediately. Once that happens the clogged filter causes the new pump to run dry, pump overheats and burns out or the pressure falls off and gives you fuel starvation symptoms.

I've had mr2's for 19 years and I flush my tanks and change the pump's filter every 3 years.

If your mechanic didn't charge you for a tank flush, you didn't get one.

Your not gonna believe what comes out of these old tanks!!

mr2tim

Originally Posted by 88"s/c lil"bastard

yes i can, the car sat for five years it needed a new fuel pump, that is new.
this was done in my buddy's shop i let him get the fuel pump i don't think he cheaped out and got a uni fit i checked the prices online it was an expensive part, the one used was an exact match physically we both did the pump i payed top dollar for that pump i would hope he didn't throw a cheap aftermarket universal fit, i wouldn't know maybe there ok but i did consider the fuel pump wasn't doing its job, but doubtful,.

[88"s/c lil"bastard]

umm, yea we did not drain the tank bone dry, you could be right.
we drained it pretty good though and didn't see anything crazy i'll look in to what your telling me,. it sucks when your getting free work and your involved but it gets rushed and steps are missing from installations.

my original fuel pump didn't look as bad as yours did

[HoLun]

like i said, many things can cause bogging, unless you have fuel pressure readings when you are driving and when the bogging occurs you can keep guessing and throwing parts at it till you end up a whole new car.