Hey I am new here and have been experiencing a problem with my car a lot recently. Well I have a 95 civic eg 4 door auto to manual b18b1 swap. Recently for the past couple months I have had a bad lag issue at high rpm WOT about 5k rpm and above, it feels like it hits a brick wall. If I let off the throttle a little it feels a little better and starts to go. Almost the same thing if im in neutral it bogs at 6k rpm WOT and raps out to 7200 rpm if I let off the throttle a little. This car has a lot done to it and I have been trying to replace everything to fix the problem and searching forums for similar problems but no one has the same type of issue or never figured it out. Im wondering if this could be maybe a stretched timing belt or maybe a fuel pump? Any suggestions? Also my spark plugs are white and running lean.

I have all new sensors on the motor, new distributor, oem fuel pump (just ordered a new one), new fuel filter, new o2 sensor, checked wiring and voltage of tps (new sensor), new fpr, 275 cc injectors.

 

ecu codes?

 

What ECU are you running? Has the car been tuned to accommodate for your larger 275cc injectors??

 

No ecu codes and no I haven't chipped it yet. Was going to go get that done soon but it never acted like this before. After about 3-4k of the motor being broke in it started this. Use to run like a champ.

 

U realize you NEED to tune it with the different injectors?? Not only are the flow characteristics different, but so is the deadtime, offset, etc, etc... You cant just throw in different injectors and expect the car to run right... doesn't work like that.

 

k im going to get it tuned hopefully tomorrow. Ill let you know results.

 

Well I ended up talking to the guy who tunes my friends cars and he told me to swap back injectors which I did and I also put a new harness on to try and still doing the same thing now but kind of worse. Im just getting so irritated and cant figure out what it is!

 

u kind of answered ur own question in the first post. " loss of power at high rpms, plugs are running lean". there is a issue with the fuel.

first off.. ur lack of power is from running lean, plugs are being fouled. u may be fine at idle and low rpms but when u go wot the fuel pressure just isnt up there. clogged filter,kinked fuel lines, fuel leak at injector/regulator/banjo etc, could also be a bad regulator. regardless low fuel pressure is most likely the issue in ur case.

should be roughly 32-36 idle and 40-47 wot for fuel pressure if u do a check. you may be fine at idle with say 30 psi but if u go wot ur probably only getting 35, which means running lean.

just check everything fuel related

 

Do you have another stock fuel pressure regulator you can swap in?

 

I have tried a lot with the fuel. I have done three FPR, i switched back to regular injectors yesterday, has new fuel filter, has new fuel rail, has a diff fuel pump from a friend who has it running well in his eg. I have tried switching out the main relays to see if faulty. But nothing I can find seems to work. I'm just wondering if it might be in the fuel lines? I am going to try and hook up a gauge to it and see what I get because I have an aftermarket fuel filter.

 

possibly clogged cat .. make sure to use shielded wire for the knock sensor addition

 

I doubt he's running an ECU with a knock board...

 

No I don't have a knock sensor on mine. it is obd1 and it has a brand new exhaust from headers back including cat (high flow). I even took out my o2 sensor to check it out and ran the same. Today I took it on a drive and it seems like when the car first starts in the morning and you run it, it runs perfect. But the more and more i drive it through the day it gets wore and worse and today didn't had no power after 4k rpm and couldn't get the car to go... Im so lost. Could it be a coolant temp sens?

 

Oh and my motor seems to run really hot but the gauge shows it running perfectly fine and fan kicks on and off all the time. Its just the motor seems really hot when I open the hood. Not sure whats going on but trying to get it fixed for summer.

 

running rich usually the motor gets hotter. not sure if its the same if running lean

 

ok so I did some digging into it when I replaced my rear main seal and I knew it had to be a fuel issue. So I started with checking fuel pressure and I checked it at the fuel filter after the filter and was reading 65 psi and knew that couldn't be right. I even unplugged the FPR from its vacuum and still said 65 psi. So I knew there had to be a plug somewhere. Checked the return line and everything. Well come to find out I had put a rubber o ring between the fuel diaphragm and the fuel line on the fuel rail. I had lost the old metal gasket and guess I replaced it with that o ring and I just took it out and replaced with the rite gasket and she runs like a charm. Still got to get it tuned though.