hybrid_vtec

Dont give me the search crap. I searched and only found 2 articles, neither of which had a definitive solution!


Just did a tune up on my 98 Prelude b/c I am about to drive across the country( I am moving). While driving the other day, I threw a code 71 while sitting at a stop light. My idle went from 800 down to 500. It sits at 500 rpm without any bounce. The misfire only seems to happen at idle, and only after teh engine is warmed up. It is a random condition. Sometimes it does it, sometimes it idles fine.

So far, I have replaced the plugs (twice), wires, cap, rotor, and air filter. I did a valve adjust, compression check, and ran fuel system cleaner.

I am going to change the fuel filter today. I am also going to test injector #1. It is functioning, b/c I hear it clicking but I am afraid it may be internally clogged or flowing insufficiently.

Other than this, I am completely stumped!!! So I am turning to you guys for help. The misfire is in Cylinder #1 only, and the only code being thrown is 71! This is driving me nuts!!

Shakes

I'm going to assume your wifes car has about 100k on it which is when the 5th gen dizzys have a tendency to go out. Have you gotten your cel 9 yet?

limpmode

Try cleaning your EGR valve and the EGR ports. The replacement port plugs are $0.60 at the dealership, you will need 6. Carb cleaner will do the trick.


When did he say it was his wife's car? did i miss that?

limpmode

or like shakes said the dizzy would be the next to check. the CYP could be going out too (in the diz)

Shakes

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by limpmode &raquo;</TD></TR><TR><TD CLASS="quote">Try cleaning your EGR valve and the EGR ports. The replacement port plugs are $0.60 at the dealership, you will need 6. Carb cleaner will do the trick. </TD></TR></TABLE>

replacement port plugs? When we took my roomates off I never noticed anything like that. Got any pics of it?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by limpmode &raquo;</TD></TR><TR><TD CLASS="quote">
When did he say it was his wife's car? did i miss that?</TD></TR></TABLE>

I know him. He has a 180whp LS hatch, his wife has a stock 5th gen.

Shakes

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by limpmode &raquo;</TD></TR><TR><TD CLASS="quote">or like shakes said the dizzy would be the next to check. the CYP could be going out too (in the diz)</TD></TR></TABLE>

thing about the cyp sensor is if you ever try to replace it you will most likely fail miserably. james (98typeSH) did and ended up getting a whole new dizzy to fix the issue.

mgags7

replacing any one sensor in there is close to impossible......the wires dont like to separate....

what i did when my distributor went out was gut an jdm f22 dist and swap those guts into my h22 dist housing

limpmode

You will soon get all cylinder misfire codes, I bet.



These are the ports on top of the IM

close up of port plugs:


the arrows show the port plugs. Pull the clockradio/ECU fuse under the hood. Take off at least the manifold chamber and the fuel rail for accessibility. You have to drill these plugs and the best thing to use to get them out is a 2lb slide hammer. You can use a screw and then pull it with a claw hammer if you can not find a small slide hammer, as I had to do. I just made sure to use strong screws and a block of wood under the hammer so i would'nt f up the IM. These can be a bitch to get out as the originals are solid brass and in pretty tight. make sure you cover any openings (manifold runners, ports (if you take the IM off, you don't have to tho), etc just to keep the brass shards out of the motor. Then shoot it with some carb cleaner and use a probe or punch to get any big lumps of carbon free. you'll have to poke it pretty good. when it's good and clean then lightly hammer the replacement plugs in and reassemble. put the fuse back in and fire up. It may be slow to turn over b/c of all the carb cleaner/carbon. You should be fine after that. I cleaned just the EGR valve again a week later just for good measure. Problem solved.

PS-- this procedure is not in the FSM.

Hope this helps.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">replacing any one sensor in there is close to impossible......the wires dont like to separate....

what i did when my distributor went out was gut an jdm f22 dist and swap those guts into my h22 dist housing </TD></TR></TABLE>

The FSM actually says to not dissasemble the CYP or other sensors anyway. I switched dizzy guts trying to solve this exact problem too.





Modified by limpmode at 1:14 AM 4/27/2006

limpmode

and no one make fun of the missing fuel rail nut. I accidentally broke the stud and had to get a new one.

edit: also i never threw an EGR code (P1382 i think) either.

hybrid_vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Shakes &raquo;</TD></TR><TR><TD CLASS="quote">I'm going to assume your wifes car has about 100k on it which is when the 5th gen dizzys have a tendency to go out. Have you gotten your cel 9 yet? </TD></TR></TABLE>

No code 9 yet!

The prelude is my daily driver, the formula firebird is the car I bought for my wife.

Thanks guys, I will try it tonight and let you know what happens!

hybrid_vtec

Okay, I did it! First start up was very rough, but this morning it runs much smoother. I am about to go drive it around some more to let the motor get hot. We will see what happens.

limpmode

I should have done a write up for this procedure with pics and all. I don't think there is one on here and i know it's not in the service manual. Too bad I had to do it as quickly as possible since i do not have a garage available and have to work on it on the curb. Living in the city sucks.

Good to hear it worked, glad we could help.

At least you don't have the older manifolds, you had to drill into the mani itself before they put those ports in it.

hybrid_vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by limpmode &raquo;</TD></TR><TR><TD CLASS="quote">I should have done a write up for this procedure with pics and all. I don't think there is one on here and i know it's not in the service manual. Too bad I had to do it as quickly as possible since i do not have a garage available and have to work on it on the curb. Living in the city sucks.

Good to hear it worked, glad we could help.

At least you don't have the older manifolds, you had to drill into the mani itself before they put those ports in it. </TD></TR></TABLE>



So far after driving over 100 miles yesterday, The problem has not returned. I just hope that was it, since I have to drive from CA to VA now!

Thanks for the help guys! X 10

ShinobiLude

Good luck man...i live in Blacksburg, VA. You'll have to show me exactly what you did to your car when you back...plus i want to see the condition of your car after your drive from freakin the other side of the world. I think your only 40 minutes from VT.

limpmode

Are you moving to or away from VA?