ywsek

After a lot of searching, I cannot find a thread giving me an answer to this and cannot locate the problem.

Background:
-96cx auto => 98dx d16y7 manual
-unsure if the idle problem was present before engine change (bought w/ blown motor)

Symptoms:
-Warm Idle => surging / fluctuating idle (no tach but I would guess 600-2000rpm constantly)
-Cold startup => motor wants to almost shut off
-Turn off motor => rough / unpleasant
-No CEL

Already replaced / done:
-PCV valve
-IAC valve
-Throttle Body
-Intake manifold gasket
-tried another intake manifold
-O2 sensor
-98dx manual ECM / ECU P2E
-tried another P2E
-Purge control valve
-Map sensor
-Spark plugs + wires
-Checked for vacuum leak (plug lower throttle hole, engine almost dies)
-98 charcoal vacuum canister
-I have drained and refilled the coolant, I left the motor running with no load while the coolant cap was only slightly tightened like in the manual. I am unsure if this is the correct way.

I need help


Modified by ywsek at 6:28 PM 3/11/2007

Boostedb20EH2

Ha wow for once someone posts an idle problem after actually checking everything out first bump for this guy getting some help cause i dont have a damn clue ,seems like he has checked everything.

BlackBeastEK

FITV ? did you check that one

Boostedb20EH2

I would of suggested that,but im pretty sure they did away with those with obd2,correct me if im wrong.

92ehatch

obd2 = no FITV you are correct.

im stumped....

did you check the throttle cable to make sure it isnt too tight?

how bout TPS sensor

JACER63

u could try and reset ecu by takin pos and neg off battery and touch together for 15 secs to drain out residual power . then start car and dont touch anything i.e ,no throttle all accesories off and let idle for 15-20 mins .im really stump with your problem too. gl please chk your timing also..

jibs

Are you using the IAC valve off the automatic or are you using the manual trans IAC? I ask because the 96-98 auto trans has a different idle speed adjustment procedure than the manual trans. I think the manual IAC is a 2 wire and the auto trans IAC is a 3 wire.

If you are using the Auto IAC with the manual ecu...? I dunno


edit: I think the manual trans has the iac on the firewall, the auto is on the bottom of the tb. You need a manual, 2 wire iac


Modified by jibs at 2:07 PM 3/11/2007

ywsek

I have tried three different IAC, they each have two plugs for manual trans. The IAC is mounted away from the firewall on the y7 lower throttle body. I have also replaced the TPS when I replaced the intake manifold (most sensors).
JACER63, I haven't checked the ignition timing and that is the step that I will probably have to take next, I was just unsure if ignition timing could cause a severe fluctuation.
I don't believe the cam timing is the problem?
92ehatch, I have attempted to adjust the throttle cable several times.
Thanks guys, keep em coming!

Also, the motor was running fine before it was installed with no problems what so ever. Will / Should I take it to the Honda dealer and have them inspect and try / repair this problem for an arm and leg?

Sean DM

me and my friend had the SAME exact problem with his hatch..
it jumped from 900-2000 constantly. same symtoms and all.

and we did every single thing you did to.

and we still have no idea what the hel was the problem.

O and it was the same motr.

Boostedb20EH2

Where about in ohio do you live?

jibs

Was the original iac a 3 wire or 2 wire? What I was getting at with the iac is that your car was originally a automatic, which I think has a 3 wire iac. Your harness as it plugs into the ecu will be pinned for the 3 wire and not the 2 wire. I would check the pin outs to be sure.
http://www.ff-squad.com/tech/w...8.jpg

ywsek

I believe both the sohc auto and manual use 3 pinout for iac but the sohc vtec / b-series is when the 2 pinout issue is brought up. I have checked both manual and auto iac and there are 3 wires.

I'm located about 30mins south from cleveland


Modified by ywsek at 1:32 PM 3/13/2007

93FlatBlackHatch

I had the same problem in my car after I did a B16 swap. I checked everything you did. I took it to a local honda shop and and they put a different tb on the car and it fixed the problem. Since then I bought a spoon tb and the jumpy idle is back. I dont understand why, it idles fine untill the car is warmed up so I am thinking its coolant related but my tb doesnt have a fitv since its odb2.

LowTEC SaiMike

iTrader: (7)

timing is good ? o everything plugged up ? , like there is a crank position sensor or something like that

Boostedb20EH2

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ywsek &raquo;</TD></TR><TR><TD CLASS="quote">
I'm located about 30mins south from cleveland


Modified by ywsek at 1:32 PM 3/13/2007</TD></TR></TABLE>'
I'm about 45 minutes south.

kawickstrom

i have the same problem but a friend of mine said to change out the coolant temperature sensor. i dont have the money or i would do it. i have already changed most of those things.

jibs

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ywsek &raquo;</TD></TR><TR><TD CLASS="quote">I believe both the sohc auto and manual use 3 pinout for iac but the sohc vtec / b-series is when the 2 pinout issue is brought up. I have checked both manual and auto iac and there are 3 wires.</TD></TR></TABLE>

I checked my factory service manual for the 96-98 years.
Page 11-126 details the iac for the d16y5 and d16y8 with manual trans. It shows a 2 prong plug.

Page 11-128 details the iac for ALL automatic trannys and the d16y7 engine with either the manual or auto tranny. This page shows the 3 prong plug.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ywsek &raquo;</TD></TR><TR><TD CLASS="quote">I have tried three different IAC, they each have two plugs for manual trans.</TD></TR></TABLE>

So, per the factory manual you should have an iac with a 3 prong plug. This is too much thinking, it makes my head hurt. I will be very curious as to the outcome. Good luck and keep us posted!

ywsek

yes, I mistakened, what i meant to say was they each have 3 plug, as in my previous post.
i have tried changing the coolant thermostat and this doesn't help, i have many parts from a manual 98 dx that the engine came from and tried several different parts, including the throttle body, even bought a third one to try.
the only thing left that i can think of is to check the timing, bleed the coolant again, and then would be to change the manifold to a y8 manifold.

one other thing that i can add is that when my brother was looking at the ecus, he noticed the 98 ecu had one or two pins that were missing from the 96 model ecu which was a sensor leading to the fuel pump, but we even placed the sensor in place and wired it up to the 98 ecu.