DragUnit

Did engine swap into my EG about a year ago. OBD2 Integra engine into my 92-95 hatch. Notice few problems during operation haven't been able to find a cause since then. Had a CEL for Primary O2. Replaced the O2 sensor and CEL went out. At start up the idle is wild revvin somewhat higher than normal, up and down between 1100 rpm to 2100 rpm. It does that for about15-20 sec then it idles down to around 800 rpm and stablizes. When driving I notice when I let off the gas and cruise it will putt (mild backfire) right after i let off the gas. Also at idles there's is a very faint putt sound. I shot the belt with a timing gun and it seems lined up but when it putts the red dot is passed the mark then comes back in line until it putts again. I've put some thought in to it over time as to the possible causes and all I can come up with is MAP sensor, IAC, or Valve timing? (friend suggested) said something about tightening all the valves. Keep in mind there is no CEL. Hopefully someone has some suggestions or things i could do to narrow the problem down. This is gonna have to be a DIY fix because place around my area either want to charge too much or don't even wanna put their hands on it because its a swap, also I don't trust people under my hood. I've installed some custom security sensors and whatnots that i don't want tampering with.
All help is appreciated

JDMlyfestyle

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DragUnit &raquo;</TD></TR><TR><TD CLASS="quote">Did engine swap into my EG about a year ago. OBD2 Integra engine into my 92-95 hatch. Notice few problems during operation haven't been able to find a cause since then. Had a CEL for Primary O2. Replaced the O2 sensor and CEL went out.

At start up the idle is wild revvin somewhat higher than normal, up and down between 1100 rpm to 2100 rpm. It does that for about15-20 sec then it idles down to around 800 rpm and stablizes.

When driving I notice when I let off the gas and cruise it will putt (mild backfire) right after i let off the gas. Also at idles there's is a very faint putt sound. I shot the belt with a timing gun and it seems lined up but when it putts the red dot is passed the mark then comes back in line until it putts again. I've put some thought in to it over time as to the possible causes and all I can come up with is MAP sensor, IAC, or Valve timing? (friend suggested) said something about tightening all the valves. Keep in mind there is no CEL.

Hopefully someone has some suggestions or things i could do to narrow the problem down. This is gonna have to be a DIY fix because place around my area either want to charge too much or don't even wanna put their hands on it because its a swap, also I don't trust people under my hood. I've installed some custom security sensors and whatnots that i don't want tampering with.
All help is appreciated </TD></TR></TABLE>

Ok first off. id be nice you could use paragraphs its much easier on your eyes and spaces out your problems correctly.

Also when you list that you have a swap please list what ECU you are using. and if you are running a chipped ECU are you running a Off the shelf program or is your vehicle actually tuned?

Flucuating idle is very common. this is mostly related to the IACV or the Fast Idle Valve.

backfiring/putting problem is usually ignition related do a tune up and see if it helps. also if you have a chipped ecu you could have a chip that has too much advanced or retarded igntion values. or you could just be running rich which can bog the engine slight and create a put put