Idle very high, please help asap.

[nail4545]

Hi, I have a 1988 honda accord lxi, fuel injected. My car has recently had new plugs, and alternator replaced. Check engine light came on for 15 minutes 3 days ago at the same time my battery light was on for my alternator going out, so replaced alternator and checked the led lights to see what the problem was and it said bad iacv. Lately I have had a intermitting starting issue with it starting then dying out, then it will start back up. Runs fine, sometimes rougher idle. Then last night put on a new pcv valve and drove it for 5 minutes then came to light and my idle in gear was around 1500, put it in park and almost 3000rpms. Same thing this morning after i disconnected the battery to reset. So I am wondering what to do, it is just weird that when I put the pcv valve in this happened. I am thinking i should clean the iac valve out today. Please help with any suggestions.

[charliekuney]

There are several coolant hoses within the vicinity of the IACV. If any of those leak, they will adversely affect the idle in the ways you have described. Take soapy water and check for any leaks.

[nail4545]

Yeah, I will check that when I get off work. I noticed this morning that the coolant was a little low. Thanks. I will let you know if that is it.

[nail4545]

I just checked at work, has a water leak. Cannot see where it is coming from, maybe water pump, its on left side of engine. I will get some jack stands after work and see if I can figure it out, will a leaking water pump do it.

[charliekuney]

I just checked at work, has a water leak. Cannot see where it is coming from, maybe water pump, its on left side of engine. I will get some jack stands after work and see if I can figure it out, will a leaking water pump do it.

That's what my dad assumed when one of my coupes did this, but it just happened to be the hose that went from the valve down to/near the pump.

[Demon1024]

the front left side of the radiator, the water pump,the hoes running from the iacv and the seal behind the water pump if the pipe behind the pump has been moved. i think that's everything on the driverside. well or the head gasket could leak over there too.....

[nail4545]

Well, replaced water pump, installed a new pcv valve, still the same thing. When the original pcv valve was tooken it out it shattered, so maybe some plastic went down into where the pcv mounts. Just a thought. Today my engine temp gauge quit working again. It happened before and it was the engine temp sensor, so I am waiting for the check engine light to come back on to see what it is. I think I might have to take her to the shop. Also forgot to mention I cleaned the iacv out also. Begining to dislike honda now.lol.

[Dr_Snooz]

You really want to get out of the habit of seeing a light and assuming it means you need to replace a part. That's a good way to spend a lot of money and be frustrated. You have to troubleshoot and verify that a part is bad before replacing.

In this case, it does indeed sound as if the IACV has gone belly up, but you want to proceed through the troubleshooting section of the manual before making that determination and spending money on a new one. The troubleshooting section starts on p. 12-43 of the manual I linked to in your other thread. Do the procedure and see what you learn. If you have to replace the IACV, I'd get one from the junkyard. They don't go bad often, so you have a good chance of getting a good one at the yard.

Good luck.

[AZmike]

I've had bad luck using non-Honda PCV valves. I didn't get my idle back to normal until I replaced my auto parts store PCV valve with the Honda part. The other valves ( I tried two different brands) seemed to leak too much air past from the crankcase.