FrostByte27

Hello all,

Wondering if anyone has had a solution for a problem like this. 2000 Civic SI.

We rebuilt the engine, and put it back into the car. We started and stopped the engine many times, checking codes, fixing various issues. Now the car is running just fine, no codes, drove it home.

Saturday, I drove it about 60 miles, parked it in the street to clean out the garage. 1 hr later go to start it, nothing. Then tried a few more times, and it ran, but very weak, and finally died half way into the driveway.

Another hour goes by, it started right up. Drove it into the garage and ever since, all I hear is a ticking noise in the intake when the key is in the ON position. The check engine light pulses too with the fast clicking noise. I found, once you take out the IAC plug, the fuel pump kicks on and the noise stops. Bad ground? Exposed wire?

There is a new battery in the car. We didn't test for proper voltage, or the main rely, fuses.

We did go under the dash and had the car ignition in the on position while moving wires to see if we'd find a short or lose wire. Immediately, the clicking stopped when we moved the brown connection going into the plug control panel, but tried 10-15 times after that with no other result than the clicking noise. We thought we had something, but wasn't consistent enough for the sure thing.

Any ideas?

92shade

if its a steady fast paced clicking it could be your iacv i had one go out on me like that but also make sure all grounds and connections are tight. next time it does it put your hand on the plastic part of the iacv and feel for the clicking

FrostByte27

Thanks for the reply. It is a fast paced clicking. Through the intake, it sounds like someone tapping on the intake manifold. I did make sure the battery, trans, and valve cover grounds are connected well.

I felt the IAC when it was clicking. I didn't necessarily feel the clicking on the unit, but I did unplug it again, and the clicking stopped, fuel pump kicked on. Plugged it back in. Turned off ignition, back on again, and clicking only for a second, then fuel pump kicked on again.

So the problem isn't consistent, but has something to do with the electrical circuit included with the IAC, or the IAC (I think). Also, we tried another ECU from a 99, and same problem.

I'm going to switch out the IAC with a known working one, and see what happens.

FrostByte27

I found out what the issue was. I had a bad G101 ground. This the the connection on the back left side of the block, where the coolant elbow comes out. This elbow gets it's ground from the block, and goes through the G101 bolt/wire.

Unfortunately, this part was powder coated, and causing a poor ground, something like 250 ohms. Should be 0 or real close to zero showing no resistance. We temporarily ran a wire from the battery ground to the bolt. It runs well.