So I just bought a 1992 honda civic dx hatchback tonight, and it has a few problems that I can fix, but one I am having trouble with. The guy I got it from says he had to switch the fuel pump, and he didn't buy, as he quoted "not an oem fuel pump" so ever since then, the car accelerates at a really slow pace, it take a long time for first to get up there. The people he took it to said the car is getting too much gas from this said "fuel pump" and that's why it's so darn slow! Now I know what a car should feel like, but this thing is really really slow at trying to get and go, flooring it is always necessary because the car will not go. So should I go to the store and get a new oem fuel pump? Btw the car has a d15b8 engine with a d15b7 head.

 

First off, it isn't idling that low - if it was, it would stall out.

Second off, the fuel pump doesn't control how much pressure gets to the rails, the fuel pressure regulator does. The pump only controls the maximum possible, not the current.

Check your timing (both mechanical and ignition), and check your fuel pressure. How-to's for both are available in the FAQ's sticky. While you're in there, check your spark plugs, as well as spark color.

 

For the 1st 5 mins of driving, my car idles at 2k, then drops..sometimes when im at a stop, itll idle at like 0 lol. It never did that when i had the stock manifold on. I got a free manifold with tb that was sitting outside for roughly god knows how long..so i know thats mine. How often does your car idle at 100?

 

Seems like timing is off if you have to floor it just to get moving..

 

Any CELs?

 

looking at my car, I disagree with this statement, the pressure regulator on my 98 is on the back end of the fuel rail(drivers side) and inlet (supply) is on passenger side. The below is my understanding:

the regulator is a mechanical diaphragm controlled by intake vacuum, when there is high vacuum it opens the diaphragm thus recirculating fuel back to the tank dropping the fuel pressure in the system. When there is light vacuum its unable to overcome the spring in the mechanical regulator thus allowing full pressure from fuel system and not allowing the diaphragm to open.

So fuel pump provides a fairly consistent pressure to the fuel delivery system and the regulator dumps excess fuel depending on the vacuum of the intake system. So just for numbers application to it

not accurate numbers but for example

Pump supplies 1 gal/min
car needs .1 gal/min at ilde
regulator is activated by vacuum dumping .9 gal/min

pump supplies 1 gal/min
car needs .3 gal/min at 25mph
regulator has less vacuum thus dumping .7 gal/min

so pump dictates how much fuel gets to the rails, but the pressure regulator dumps excess

if my understanding is wrong could someone please post a correction!

 

Mine started idling at like "100" a few weeks ago at stop lights and such but it's a stock d15b8. I don't have to floor it to get going though. I'm curious to find out what your problem turns out to be.

 

Maybe dirty iacv?

 

Your understanding is flawed. The FPR doesn't control how much pressure goes back to the tank, it controls how much pressure goes to the injectors, and lets the rest go back to the tank. That's why you can toss a high-flowing Walbro fuel pump on a completely stock Civic without any problems.

 

you just said the same thing I did, it releases pressure that isnt needed back to the tank and drops it in the rail to what is required.

 

i checked the cel codes and it was throwing a 14 and a 41, i cleaned the iacv and it still throwing that code, the 41 code, primary oxygen sensor heater, im not sure what to do about that. i changed the idle speed to about 800 but it fluctuates to 1000 here and there. the car accelerates extremely slow, and when i go into 2nd gear, i floor and and i get no response whatsoever.so what should i do?

 

Not trying to be a smart *** here, but the ideal answer would be "find a reputable mechanic".