I just bought a 98 civic ex automatic 2 dr with a D16y7....for almost nothing...well the reason for it being cheap is that the previous owner did a engine swap, along with replacing the header. This car has a terrible idle surge, the surge at idle goes from 1200 to 2200. When driving the car idle problem seems to stop around 60-70 mph. The o2 heater sensor is not connected to the exhaust but is connected to the plug and the guy did a cut job where the new header fit..cutting the exhaust shorter for a fit while forgeting a hole for the o2 htr sensor. I've replaced the map sensor and the throttle body. I've also spent the last 2 days combing for a vacuum leak. ( none found) I also noticed a nut missing from the header that was installed. ( maybe a problem) I put a scan tool on the car and got a P0135 dtc code, i also did a freeze frame and got the following:

Throttle position - 9.4%
Engine Rpm - 2824 rpm
Load Valve - 24.3%
Map sensor - 25kpa
Intake Air Temp - 82 F
Short term fuel trim - 0.0%
Long term fuel trim - 0.0%
Short term fuel trim3 - 100.6%
Long term fuel trim3 - 100.6%
Vehicle speed - 3mph
Fuel system 2 - open
Fuel system 2 - N/A

I've read and read through the forums and still no help....so any thought would be much appreciated. I'll post a vid later today to show exactly what this 4 wheel headache is doing.



Modified by SEgrnTeg at 1:06 PM 4/2/2008

 

http://s232.photobucket.com/al...3.flv


Modified by SEgrnTeg at 1:02 PM 4/2/2008

 

a NooB can't get love in the house of Honda-tech?

 

hey man i have a 96 jdm gsr and it use to do the same thing you should clean out your iac and make sure all the vacuum lines are where they are suppose to be, that was my main problem, also try cleaning your fitv valve(i dont have one but its a common problem)

 

i'm doing that now....i'm also gonna tap the exhaust to reinstall to o2 heater sensor, to make absolute that it is faulty per scan tool. i'll report back

 

cool tell us how it goes

 

well...no vacuum leaks...and i don't have a Fast Idle Thermo Valve, i also cleaned the Idle Air Control Valve, no improvement!!!...so....i'm stumped.

 

You don't have one O_O? Well I guess you should check all the connectors, cause I had that problem and mine was because I had two plugs switched around. Double check all the wiring on the IM and surrounding areas.

 

Finally rain has stopped here, gonna spend the day with muh new baby. Wanted to say thanks for the info guys! I'll report later today.

 

Idle Air Control Valve......$164.75 AutoZone....Thanks Everyone

 

yeah check your IAC i did a mini me y8 swap in my car and the idle was horrible and we went through and checked the entire electrical system and fount out the ecu and harness was shot....just an idea.

 

yeah check your IAC i did a mini me y8 swap in my car and the idle was horrible and we went through and checked the entire electrical system and fount out the ecu and harness was shot the tps was at 9....just an idea.

 

Car is fixed and idling fine....thx again

 

what was it?

 

ECU and IACV....previous dipshit did a engine swap , the car had a d16y8 vtec, it was swapped for d16y7 non vtec...the original ECU for D16y8 gave irratic idle, speedo problems....changed the ECU...seems to be working fine....Now im looking for a d16y8 to change it back to original factory...what a headache, but i only gave $500 bucks for it...

 

thats exactly what mine was doing, its a pain in the *** but once you get it figured out its all goood