mig4444

Hi all new guy here. Well I bought a 98 civic dx with a blown head gasket, No water in oil but it did over heat, there was sludge in the coolant reservoir.
Anyways I went ahead and change the head gasket got the head machined everything went back perfectly, now the problem Im having is, the dam idle is either to high when I start it and when I put it in drive it idles super low to almost where it wants to die. While driving the car after and its completely warm it will idle fine at a stop light. any help will be greatly appreciated

mig4444

oh almost forgot to mention I did burp the cooling system also set the timing at 13 * the only thing I have not done is reset the ecu don't know how or if its needed.. I did take the car for a long drive for about an hour .. Iheard that this helps the ecu. Car runs fine but it idles poorly..

TomCat39

Supposed to be 16 degrees not 13.

The red mark (middle of the three marks close together on the crank shaft pulley).

Also, what motor is in your DX or is it bone stock?

mig4444

Thanks for replying.. yes its bone stock..gonna set the timing at 16 right now.

mig4444

ok so I set the timing at 16*.. I actually got another iacv from my buddies car, and now I got a code for po113 and po301 I went ahead and used his spark plug wires and cap and rotor and its still doing the same damn thing..
I'm wondering if maybe some how some way it might of jumped timing on the timing belt when I did the head gasket.. I did marked everything I could of think of and all the marks lined up perfectly when everything went back in..

Wdpfreak145

Take care of the CEL codes first. One is IAT (intake temp sensor) and the other is a cyl 1 misfire.

Second, take a look in the sticky and follow the mechanical timing procedure for your specific engine. If you have any kind of head swap ("mini-me swap") then timing procedure might not be dictated by the service manual. Verify that timing is dead on by the factory marks- not your own.

Lastly, poor idle isn't a symptom of timing. More than likely has to do with the cooling system. Follow the instructions for FITV and IACV servicing (located in the sticky) before you replace yours with your buddy's IACV. Brake parts cleaner and q-tips do the job for me every time for the IACV, and I like to back my FITV out 1-1.5 full turns from the bottom when cleaning it. Make sure you bleed the coolant properly too- air in the system will cause things to act wonky.

mig4444

Ok so I set the timing 16° now Im getting a code po301 I have checked and tested the spark plugs, spark plug wires, cap and rotor, and the injectors.
After I did all that I went ahead and turned the check engine light off it drove good idle.was at about 800, but.when I put it in drive it idles super low almost to where it wants.to die then check engine light goes blinking and it shows p1399...

TomCat39

Did you double check your mechanical timing like wdpfreak suggested? You yourself wondered if you were a tooth off.

Also at any point did you mess with the idle adjustments screw? When you first start the motor it should jump to about 1500 rpm and start to drop as it warms up.

If you adjusted the idle screw on a whim you could have basically been your own folly.

Being you have a 98, I don't believe it has the FITV so you only have to be concerned with the IACV and once the car is fully warm you can set idle properly. This is also assuming stock 98 DX. You might also look at seeing if your TPS is providing the proper voltage 0.48v when the throttle is fully closed. Whatever you do, don't mess with the throttle plate screw. That is set at factory and should never be tampered with.

nub

OP says it's bone stock, 98 LX, so it should be a Y7 and is pulling P codes so it still has an OBD2 ecu.

All OBD2 A or B, D series have a base ignition timing of 12* btdc. If you set ignition timing to the middle of the three marks you're fine. If you're using a dial back timing light set to 16* redo it.

If this is still the stock Y7 it'll have a 3 wire IACV. OBD2 doesn't use a FITV and aren't as sensitive to air in the coolant as older versions when it comes to funky idle issues.

Remove and clean the IACV if you havent already. The 3 wire uses a rotary valve vs the 2 wires plunger type. The rotary type is more sensitive to gunk and needs to rotate freely.

mig4444

Thanks tomcat and nub for reply.. I did double checked my mechanical timing and everything is good.. I purge the cooling system again .( car was on jackstands cap off with heater full blast for while no bubbles came out after a long while) also I did have the timing set at 12° before .. I went ahead and set it at 16° now.. and its still has low rpm's... I never touched the idle screw so I know it hasnt been messed with.. also cleaned out.the iacv.. and got a different one which I cleaned before I put it in but the problem persists and now I have po301 or.p1399.....

nub

Set the ignition timing to 12*. Having it at 16* is why you're getting the missfire codes.

Just so you know you don't run the fan with the heat, you just put you temp control to hot so coolant is circulating through the heater core.

When you're setting the ignition timing are you...doing it with the engine at normal operating temperature? Have proper idle speed? Have the service check connctor jumped?

With the ignition timing set to 12* is your distributor roughly in the middle of its adjusment range?

If you engine is stock 12* is the middle line in the group of three on the crank pulley. Confirm you have a D16Y7.

mig4444

Hey nub, yes to all of the above and also its a stock motor d16y7...its really frustrating..the only thing I can think off is maybe it has to do with the computer.. Im so ready to just crash this damn car into a tree!!!

nub

Doubtful the ecu is the problem if you not getting additional codes. One of the advantages of OBD2 is the codes are very specific compared to older diagnostic systems.

If you've eliminated the missfire codes something you could try for your idle issue. With a cold engine remove the "back up" fuse from the under hood fuse box to clear the ecu. Be aware this will also clear the memory of your radio so if you have a radio with a security code you'll need the code to unlock it.

Make sure ALL acessories are off. Replace the fuse and start the car and let it idle. Don't touch anything electrical or mechanical, no throttle input, no radio, no lights including the dome, nothing. Let it idle until the cooling fan cycles twice.

After this see if the idle issue you described has changed.

TomCat39

In another thread for the D16Z6 they took the crank pulley, measured the distance from the white (TDC) mark to the middle red mark, did the math and said it worked out to be 16 degrees from TDC.

Everything else I've always read said FI is 16 degrees while the old carb systems were 18 degrees.

I'm confused, this is the first time I've ever seen mention of 12 degrees. Is it pre obd2 that the 16/18 applies to?

Why would the math work out to put the middle mark at 16 degrees variance from the white TDC mark?

Of note, I've only ever used the most basic of timing lights that require using the marks on the crank pulleys, nothing fancy like the one you mentioned. So no matter what degrees, I'd be setting it to the marks the manual specifies.

nub

95 and older D series are 16* and 18*. In 96 it changed to 12*.

I only mentioned the dial back timing light because OP said he set it to 12 and then set it to 16. There is no mark for 16* on a Y7 crank pulley so how does he know it's set to 16*. Timing marks on all of the Y series a 10-12-14

With a dial back light you set your desired timing on the display, the lights flash is retarded by that amount and you line the pointer up to the TDC mark on the pulley.

They're helpful if your crank pulley is marked incorrect or you're trying to set timing to a value not marked on it.

TomCat39

Thanks for the info. I always seem to learn something new almost every day here at H-T.

mig4444

[QUOTE=nub;49753558]Doubtful the ecu is the problem if you not getting additional codes. One of the advantages of OBD2 is the codes are very specific compared to older diagnostic systems.

If you've eliminated the missfire codes something you could try for your idle issue. With a cold engine remove the "back up" fuse from the under hood fuse box to clear the ecu. Be aware this will also clear the memory of your radio so if you have a radio with a security code you'll need the code to unlock it.



so I'm looking for the back up fuse on the manual would it be #41 or #47.
#41 is battery(power distribution) #47 is (back up radio)..
thanks guys I really appreciate the help

TomCat39

It should be a 7.5 Amp fuse in the Under hood fuse box. Don't remember the fuse number off the top of my head.

mig4444

Ok well I tried reseting the ecu pulled the back up fuse let it run till the fan came on twice and a flashing CEl code p1399 came on shortly after warm up... the only.thing I can think off is I somehow messed up installing the timing belt back on or the head that I installed bad or incorrect and maybe it jumped a tooth or two or maybe valves were set wrong..im going to go back and do the timing belt again just to be sure...

Former User

Check the plugs (NGK only), wires (OEM only), cap, and rotor. Replace the fuel filter if old. Then go from there.

mig4444

Ok so I had to buy a new compression tester cause my 6 year old thought it was some kind of toy and banged it around so it wasnt working properly.
I did a compression test and #1, 90 #2,120 #3,150 and #4,160... do valves have.to be adjusted cold then after warm up adjusted again?

TomCat39

No cold adjustment only is the way I learned it.

A leak down test will tell you if it's valve side or ring side if it tells you anything at all.

Taking apart is the only way to know what specifically the problem is like a crack in the head, burnt valve, crack in the block, a broken piston ring, bad ring land(s) etc etc.

mig4444

Finally fixed!!! It was a burnt valve on cylinder 1.. got another head from junkyard machined it..replaced valves with new ones.. It runs super smooth now... thank you to those who helped me out trying to figure this mess out...