JDM d15b ROUGH idle issue....

[a94civicex]

So I just recently got my 95' civic eg8....! For some reason it's got a low idle issue....! Things I've done so far to try to get the idle to break free from the roughness....!

1. Advanced Distributor a little (didn't raise to idle)
2. Replaced all spark plugs & wires (didn't raise idle)
3. Adjusted the flat head screw on Intake Manifold to allow more air flow (raised a little)
4. Replaced Timing Belt (didn't raise idle)

The car has a JDM d15b in it with 156k miles....! It's got me puzzled....!
Has anyone with this motor ever had this happen....? What can I do to fix this small issue....? Should I adjust the throttle cable to bring the idle up to around 900-1000rpm at idle because right now it's idleing sometimes around 500 rpm & other time around 700-800rpm....????.... And once it breaks free of 1000rpm it clears up runs nice and string hitting (vtec hard).... Could the injectors need replacing, bad tps, bad egr valve, bad iacv, or could I be running weak spark plugs & wires, maybe need tuned, or possibly wrong gas (running regular unleaded)....

(sometimes it's sounds like the intake will suck in some air, then stop when it idles around 500rpm)

[a94civicex]

Does anyone have any advice on what I should do....?

[geezy]

check for vacuum leaks

[a94civicex]

check for vacuum leaks

No vac leaks....! Believe my rear motor mount is bad, which would cause the motor to do what it's doing....!

[blown_ss]

No vac leaks....! Believe my rear motor mount is bad, which would cause the motor to do what it's doing....!

that wouldnt cause a low idle.

[GREENKOOLAID]

my jdm d15b does it to.... but i have more problems than that if you read up on my post and you know of any thing you could help me out with would be nice.... try adjust your dizzy back and forth it fixed mine some what.

[a94civicex]

that wouldnt cause a low idle.

It may not cause the low idle issue I'm having but it felt like my motor was going to come through the firewall since the idle is low.... Just replaced my rear mount today and it helped it out alot but my car needs a good tune....!

[a94civicex]

my jdm d15b does it to.... but i have more problems than that if you read up on my post and you know of any thing you could help me out with would be nice.... try adjust your dizzy back and forth it fixed mine some what.

I've already adjusted my dizzy back & forth & nothing changed at all....!

[preferredduck]

hey ok if you did not put a jumper wire in the service connector then you did not adjust the timing. it is a blue 2 pin connector on passenger side near the ecu. to properly adjust the idle disconnect the iacv and adjust the the throttle screw at the TB, then reset the ecu after doing this. make sure the car is at normal operating temp when you do this and if it's too low it may stall. with the iaxc unplugged the idle should be a 500, if it stalls have a friend give it a little gas to keep it alive until it reaches where it should. also what intake manifold and
tb are you using, i know this sounds like a dumb question but sometimes the wrong one will cause issues.

[GREENKOOLAID]

well all i can say is if what he said doesn't work then make sure you dont have any intake leaks to wear its sucking in to much air cuz mine was doing it to till i had to buy a new intake gasket

[cprtyler]

did you clean the tb and adjust the cable again remember it was sticking real bad at my house the other day

[B20B!Ithink?]

advance ur TPS itll raise the idle

[a94civicex]

advance ur TPS itll raise the idle

TPS (throttle position sensor).... ive adjusted some slack on the throttle cable by tightening it up some, but not alot.... how do you advance the TPS....?

i really think it just needs to be tuned.... but i may be wrong....

[D3UC3S]

run premium...it wont help your problem(preffered duck covered that), but it is better for the vtec motor.

[.:Stirfry:.]

have you used a timing light?

[a94civicex]

have you used a timing light?

No, I don't know anyone around me that would know what they are doing.... If it's not "dead center" would that cause the low idle problem I'm having....?

[Batlground]

give us a call if you want to get it tuned. If everything is mechanically working we can raise the idle for you in the computer.

[a94civicex]

give us a call if you want to get it tuned. If everything is mechanically working we can raise the idle for you in the computer.

And how much will that be....

[Batlground]

you can email us at [email protected] for a quote. I will pm you one as well.

[a94civicex]

you can email us at [email protected] for a quote. I will pm you one as well.

okay is that the best yall can do on a N/A motor?

[xero_xero]

it sounds like a vacuum leak. or lac of an imput from a vacuum sensor.

if you received a jdm d15b ffrom a 92-93 civic then it will have a remote map sensor on the firewall. the throttle body will not.

since you have a 95, your map sensor is on the throttle body. if you did not reuse your intake and you utilized a 92-93 intake then it will cause this issue.

here is a pic of the map sensor on the throttle body. if you do not have one this is your problem.