O2 Sensors and Electronic Idle Control

[ChuChi]

88 Accord LXI EFI

After a little mis-adventure with a dead battery and a bad jump, my shop is telling me that I need to replace my O2 sensors and my Electronic Idle Control. They want $310 for the o2 and $220 for the idle control. Thats not really feasable right now, so I need an idea of how in depth a project this could be.

From digging through the shop manual and the forum here the O2 sensor seems like a no brainer. Maybe $80 in parts and an hour of labor. Why would they be charging $310 for it?!

Now the electronic idle control I can't seem to find much info on. I'm not completely sure what they're refering to (one of the idle valves?) or where it is. It's hard to find information when you're not sure what you're looking for and the forum search gets flooded with generic 'idle' threads.

I'll reward the most helpful answer with details of the jump gone wrong :D

[AZmike]

The valve they're referring to is on the front of the plenum. It was a 2-wire connector and one small coolant hose on each side. How did they verify the idle valve and O2 sensors are at fault?

[azazel_18_2]

yeah. What is the car doing? is it throwing a code? It is possible the mechanic is trying to rip you off. Happens all the time. Took my s10 in for an alignment and they replaced my idler arm. I went in about a month later to have some 20's put on and the same place told me my idler arm was bad. I told them I just had it replaced. They told me whoever did it ripped me off and didn't replace it. that is when I told them they were the ones that replaced it. That is when everything changed. There are alot of shady mechanics out there. Oxygen sensors around here are like $20 a piece. Tell us your problems with the car and we can tell you what you need to fix it. There are two different idle valves on this car. One on the back of the intake manifold called the fast idle valve and one on the front of the intake manifold that is called the IACV or idle air control valve. These things hardly ever go bad. I did have to replace my fast idle valve because my car was idling up then down. How embarrassing. the fast idle valve is like $90-100 and the IACV is around $200-250. I have a brand new IACV I purchased at Honda and never got around to using it. If it is your problem I would let you have it for $100 shipped. It is brand new and still in the Honda Package.

[Listen2myBASS]

they charge that much because they look for the part that costs more then a cheap replacement then charge 80$ an hour and keep your car for half a day...

[ChuChi]

I know about shady mechanics. We've used these guys for about 14 years now without a problem. For the past 2 years or so I've used them for diagnostics and immediate fixes when I don't have the time. They know their stuff and do good work. However, I don't have the details of how they confirmed these two failures. This is my girlfriend's deal so I'm letting her do all the communication. I figure I'll be doing all the verification again anyways.

The car is throwing a code. I'll absolutly confirm it once I get out there to check it (now that I've learned how to read the CEL). The CEL comes on once the car gets up to speed, usually on an on-ramp. It stays on until the car turns off. Turn it back on and the CEL is off until it gets up to speed again. O2 sensor made logical sense to me once they said it, and I felt like an idiot for not checking the code myself after I came on here.

Seperate problem, the car does idle up and down. I only notice it when parking, so the car is warm and in park. It revs from normal idle at ~800 up to 1500-1700 and back. Kinda like it's possessed. It won't stop until the car is shut off and turned back on again. Obviously something in the idle control system, but what? and where?

[AZmike]

Have you done any work on the cooling system lately? Air bubbles in the system can cause an uneven idle--they make the fast idle valve open and shut.

If the ECU is getting weird signals from a sensor--like a bad O2, it could be giving the electronic idle control valve bad commands.

Check the coolant level and the CEL and get back to us.

[azazel_18_2]

Check the CEL. I hear people talking about air bubbles causing weird idling but I never had that problem. I completely tore down and rebuilt my engine, never bled the bleader, and never had a problem. Sounds like the fast idle valve BUT check the code first and repair what is wrong. The fast idle valve will not throw a code but the IACV will. Just let us know.

[ChuChi]

No recent work on the cooling system in this car. Just replaced the radiator and did a complete flush in the Subaru, but the Honda has never leaked ;) The rev up and down is fairly slow and rythmic, ~ 1Hz. I don't think air bubbles would be that consistent.

Next step is to fix the CEL. Stay tuned...

[ChuChi]

Codes 1 and 14. O2 sensor A and the IACV. I coulda done that myself and saved lots of time :roll:

Anyway will replace the O2 sensors and see what happens. Depending on what I find I may have to take you up on that offer azazel...

[azazel_18_2]

$105 shipped or maybe some trading.

[azazel_18_2]

You will need a 7/8 wrench to change your O2 sensors. Just to let ya know.