damn honda....

[Wicked72]

So ive got a 90hatch. Has a d15b2 converted to mpfi. basically all a6 parts except i used high impedance injectors so no resistor box, and a pm6 ecu. I rebuilt the engine and did the conversion all at once over a year ago and have had no issues till now. It idles ok but a slight press of the pedal from idle to 2500rpm its acting like its got a bad miss(hard to accelerate) then after the 2500 it runs fine so basically i drive it above 2500 but has a slight miss randomly. Also i can start it up cold and run it awhile with zero issues then it start having issues after its been warmed up awhile. i have also had a random issue once the problem started where it wouldnt rev past 2500. so i turned it off and back on and it was able to stumble past 2500 again.

So i have done a ton of trouble shooting. Replaced the dizzy, checked all grounds, checked plugs and wires, tested the tps, map, swapped ecus, tested injectors(coils and fuel flow) and checked the alternator. The fuel filter is new and so is the fuel tank. everything tested is good no issues found

Im assuming the fuel pump at this point. am i missing anything else? what do you guys think?

[Todd Wilson]

Did you check the gap on the plugs?  My 86 Honda would open up the gap on the plugs if I used any plug other then what Honda recommended. It would do funky stuff like that. I replaced with I think NGK and it never gave me fits again.


Todd

[Nwcharger]

Sounds strange. I'm a honda/acura tech for a living and have been for 12 years now. Ef civic hatch is my favorite. I own a jdm crx sir from Japan with a factory b16. There's a small bolt in the center of the banjo bolt on top of the fuel filter. You can put a pressure gauge there, tape it to the windshield and drive around the block. I have only replaced a few fuel pumps on hondas. They rarely have fuel delivery problems. Normally spark is the issue. Your injector setup is strange. Is you ecu flashing any codes? 

[Wicked72]

so i checked my fuel pressure and its perfect. and the ecu is flashing for the o2 sensor. which it has since the rebuild. im thinking the o2 might be sending a funky signal to the ecu? ill unplug it and see what it does. also im going to clean the hell out of the iacv and throttle body

[Wicked72]

also ill regap my plugs

[bakerhillpins]

Also i can start it up cold and run it awhile with zero issues then it start having issues after its been warmed up awhile.

You guys rambled off a lot of acronyms there that I have no F'in idea what they are but if you are running electronic equipment and it runs/tests fine while cold then start pulling/replacing individual components one at a time when hot to test for heat failure.  Our minivan has f'ed up injectors that crap out (results in misfire codes) when they heat soak in the summer.  Since we live in a cooler climate it's not frequent and it clears the error in a few days of normal temps. Just a PITA if it occurs around inspection time.   

[Wicked72]

SO.... figured it out. ROOKIE mistake that drove me crazy. So the dizzy(distributor) was the issue... so the new one that i had got was the right one however they did a color code change which at one point i made some tech notes for it so i wouldnt screw that up..again. Well when i thought it wasnt the dizzy i went ahead and put my old one back on!! so during the extra trouble shooting i ended up pulling the cap off and to my surprise it looked like a bomb went off in it. it was coated with some type of power, the cap was all burnt up and the rotor was falling off, just kinda hanging there. im surprised it ran...   anyway its alive once again! thanks for the help!

[Nwcharger]

SO.... figured it out. ROOKIE mistake that drove me crazy. So the dizzy(distributor) was the issue... so the new one that i had got was the right one however they did a color code change which at one point i made some tech notes for it so i wouldnt screw that up..again. Well when i thought it wasnt the dizzy i went ahead and put my old one back on!! so during the extra trouble shooting i ended up pulling the cap off and to my surprise it looked like a bomb went off in it. it was coated with some type of power, the cap was all burnt up and the rotor was falling off, just kinda hanging there. im surprised it ran...   anyway its alive once again! thanks for the help!

glad to hear you have found the problem. sounded like an electrical issue. rarely do hondas have fuel delivery problems but it does happen. just replaced a set of injectors today for running rich, maybe the second set ive ever replaced