I just swapped my 94 GSR engine into my new 2000 civic hatch. The whole car has been converted to OBD1 with a OBD1 P72 GSR ECU. I am having a problem with the car misifiring/backfiring after i drive it hard (after a couple of 8000 rpm 3rd gear pulls). When it idles, i can hear the exhaust hum and then, there will be some random "poop" sounds. And i am loosing power between 3000 to 4000 rpm at partial throttle....almost feels like the car has retarded the timing on it's own or i have lifted off the throttle. I have noticed that this misifire only happens at partial throttle or idle. BUT, if i don't pushed my car, driving at 3000 to 4000 rpm all the time, the car will drive like a champ and idle solid at 850 rpm or so with no backfire what so ever.

Another symptom is that whenever the car is cold, it will backfire but once it warms up, it will idle solid....that is until i push it hard and it wil start misifiring again. The car has new cap, rotor, and wires.

Since last year, i have had problems timing my car. Even with the distributor fully advanced, i can only get 16 degrees. All my timing markes line up and i have never been able to figure out why. I have even tried timing with 3 different timing lights with the same results. I am leaning more towards a failing distributor. Does anyone else have any other inputs or ideas they want to share??


Modified by eg-six at 6:58 PM 5/18/2003

 

what ecu are you running?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BCRUZ &raquo;</TD></TR><TR><TD CLASS="quote">what ecu are you running?</TD></TR></TABLE>

I am running a OBD1 GSR ECU.

 

i dunno ****, but im running my stock d15b7 in my 94 civic and its auto, but it does exactly the same thing. sometimes when i first start it (even if it was warmed up and only off for 5-10 min) it won't go past 4500rpm, when redline is ~6500

 

anyone?

 

My car does the same thing, ever sice I swapped in a JDM d15. If I drive the car for long periods on the highway it does it too. most people tell me it's the timing, and I've been too lazy to fix it, but if you said you corrected that, then I dunno what to say, but I'm interested in hearing what the rest of the board thinks.

 

Check your cam timing, it maybe off a tooth or so. How about the spark plugs.... Just a guess..

 

I will check the cam timing...but they all line up. I will get a set of new plugs tomorrow. I am hoping it's not the distributor because that will be $$$!

 

do you have an msd or an external coil?

 

maybe you jumped a tooth on your timing? but if you said it is correct, duno what to tell you. do you have good plugs in there? you might be predetonating.

 

my old hatch use to do it. it was just backfiring inside the exhaust. usally does it when your slowing down with closed throttle. my car was running really rich and i had a small exhaust leak at the cat because my motor mounts were crap and the motor sat in the car with a little slant and the header and cat didnt meet up perfect.
funny thing is with that small exhaust leak the car performed better than it ever did after i fixed it and ran multiple diff exhaust setups on it.

cool thing was that since i had a straight back exhaust with almost no bend, and no cat. and an open cannister. sometimes when it backfired it shot fireballs out the muffler. one time it did it at like 9000 rpm at night when i was racing someguy and it lit up my whole back window i thought a cop was pulling me over haha.
i kinda like the misfiing, gave my car character.