Hey everyone.
I have a 1995 Honda Civic Ex d16z6 that is running too rich. I bought it off some guy and the car came with a chipper p28 ecu and intake, headers, and a bigger throttle body. I have since returned the intake to stock to pass smog but the car has been throwing fuel down the exhaust and it hasn’t passed because of that. I have changed the o2 sensor and redid the ignition timing but I don’t know where else the extra fuel is coming from. The fuel pressure regulator is stock and so are the injectors. The car has a pretty normal idle but I have noticed it doesn’t reach redline. By this I mean the car just doesn’t rev pass 5k rpm. It kinda sounds as if the engine just can’t go past that or if it’s starving for air. Also I don’t feel the vtec activate ( including this in case it can be the root cause of the problems) but I’ve heard that vtec isn’t as noticeable on single cam engines. Also the engine has 300k miles



thank you for your time and interest in my post

 

Check the ECU for any codes! Most likely there is a stored code in the ECU and its causing the engine to be in Limp mode so it wont rev past 5k rpm to prevent any serious damage from happening. Use the paper clip method to retrieve the code.

Its most likely has something to do with the chipped program installed in the P28, The P28 is the correct ECU for the engine but sounds like the calibration from the added Chip needs to be checked and or changed, Some "chipped" ECUs just have bad programming or shitty work. I had seen one that was advertised as "chipped" but lacked all of the other hardware to make it work.

Find a person who can look at the settings in the ECU or try having a new base map set in the ECU and see if it drives better.

 

I did the paper clip method on the ecu and no codes popped up. The check engine light stayed solid while the SRS light was blinking consistently. I have read that a solid check engine light may be a messed up ECU and maybe the person that chipped it did it incorrectly.

 

Yes have the ECU checked or try another stock P28

 

You said it is a chipped ECU - the chip may have a tune on it that is for larger injectors. Open the ECU and cut the jumper in location J1 to return the ECU to the stock P28 map.

 

Hey.
I got the original p28 ecu and this one is finally readin the check engine Codes. So far a 22 code had popped up for the vtec solenoid but the car is running even more rich!!! My last suspicion is that the car may have bigger injectors and it’s throwing too much fuel. I tried to adjust the timing but even after advancing it as best as I can it doesn’t reach the 16 btdc and I can’t adjust it any further. The injectors I have have marking saying IPT which I know is oem and the number markings they have is 4107. I have replaced the o2 sensor as well and the 22 code is the only code popping up

 

Measure the fuel pressure, test the FPR, and check for an exhaust leak/crack in the header.

Problems with any of ^these would cause the engine to run rich.

 

I HAD THE SAME PROBLEM WHEN I PURCHASED MY CIVIC AND IS THE DIZZY . AND BY THE WAY IF YOU HAVE THE 95 HONDA CIVIC EX CANADIAN those parts that you mentioned before is factory . The D16Z6 COMES WITH 2 PIECE HEADERS, 2" MUFFLER PIPES AND OTHER PARTS THAT AMERICAN EX DONT HAVE. FOR INJECTOR I EVEN USE BEFORE 2004 TOYOTA 2.4 INJECTORS AND THE CAR RUNS PERFECT RIGHT NOW AM USING K24 INJECTORS AND IS RUNNING RICH BECAUSE THE TB IDLE SCREW IS NOT TUNE BECAUSE SOMEONE PLAYED WITH IT BECAUSE IS NOT MY ORIGINAL THAT CAME WITH THE CAR.