cool hand

The car is a 98 Civic EX 2 dr auto with the D16Y8 engine. Heres the low down.

I got the car from a friend who wrecked it and didnt have money to fix it. It needed a hood, fender, upper core support, front clip and a everything else that could be destroyed when a civic hits something hard at 50 mph. Still drove and ran like a champ, just crashed pretty bad. I pulled it into the shop and pulled all the sheet metal off to check out the situation. After making my list I shoved it back out and didn't bother to cover the open engine bay. I got distracted on other work and didnt get back to it for about 2 months. 2 months of Indiana winter weather is not a good thing.

About 3 weeks ago i got parts rounded up and got the body work finished, but the car ran terribly, idling at like 4k and then surging between 1500 and 4k.

First thing I did was throw a timing light on all the cylinders and found out one cylinder (the one that plugged into the bottom of the distributor was not firing consistantly. Pulled the cap off and water dripped out. Drainied the cap and let it dry. Fired on all cylinders...sweet right? Noipe.

Started looking for vaccum leaks as recommended by Andy at www.cornbredtuning.com. When putting my hand over the throttle body it would not die. Further investigation with a can of carb cleaner showed the intake manifold gasket was toast. Best I can tell it was a combination of lousy timing and my ignorance about the effects Indiana weather would have on an exposed engine bay. Replaced the gasket, now it dies when you cut off air at the throttle body. Sweet ready to go cruise right.....wrong.....

Now the idle was much better, but still idled very low on cold start, then surged from aound 700 to 1500rpms once warmed up. Further consultation with Andy suggested the IACV. This particular throttle body has a port at about 7 oclock and about 11 oclock. When covering the port at 11, all the happened was a little bit of vaccum, but no engine response. Covering the one at 7 oclock killed it instantly. Covering it half way brought the idle into check. Again, pointing to IACV.

Well, the IACV (this particlular model is a 3 wire setup) was ~200 buck to replace, so i figured, well I could find a throttle body, with IACV used for much cheaper. The fine people at Honda-tech had plenty of used ones to offer and I was actually a couple of hours away from buying one. During my research of how the IACV works I found this link http://ecomodder.com/forum/showthrea...ained-967.html. At the bottom of that link it discussed about how the ECM cuts fuel on deceleration based upon RPM and throttle position. Since the throttle was closed and the car was wanting to idle hirer than 1100, it was cutting fuel when it hit 1100, thne letting it go again when it got below. Again IACV.

Thinking i needed a new IACV, I had a seller send me pictures of what he had and I pulled the throttle body off to compare. Once it was off, and assuming i was getting a new one, i figured i had nothing to loose by tearing the IACV apart to see how it works. I pulled the plug of one side, and the other side had a cover that held a spring in so I pulled that part too. With the IACV all apart, the valve would not move. A little bit of persuasion freed the valve up and now it spun freely. Put everything back together, hook up all the sensors, unhooked the battery for about 5 minutes for good luck, said a little prayer and fired it up.

TADA!!!! Fast idle when cold, nice friendly low idle when warmed up.

Special thanks go out to Andy @ www.CornBredTuning.com for the crash course on hondas (Spent 10 years building and racing Mustangs, newbie here to hondas) and whoever posted this link http://ecomodder.com/forum/showthrea...ained-967.html .

Hope this helps. Moral of the story is, cover the engine bay, rain and snow are not your friends.

tx_ej8_49

Nice story. Hopefully this will help some people out with their idle issues....