I recently milled the head on my acura integra 90' 1.8, also changed the head gasket too. After putting engine components back together car started fine but it running a 2 grand and jumping down to 1 grand then back to 2 grand.....i think it has something to do with the timing but i am not sure. I set crank pully TDC then set cams TDC....did a valve adjustment.....and set dizzy. I am not sure where i went wrong. I checked timing with a gun and it is not on. Can anyone help with tips and suggestions.

 

sounds like a vacum leak to me or sensors are wrong. I had this problem when i did my skunk2 IM

 

do u mean there could be a hole in a hose or something?
also would that cause the timing to be off?

 

bump

 

Yes, a vaccum leak would be caused by a faulty hose. If the timing is off, the car may have not beeen set at TDC, start by checking that.

 

car was at TDC for sure.....what else can u suggest?

 

alot of time when people take off their head...they sometimes forget to plug their pcv valve back into the one black box...i cant remember whats that called...evap something...

*pvc's the hose from the middle of your intake manifold and it runs inbetween yours runners (into a 'L' shape valve) down to the back of the block

 

so if all hoses and plugs r connected where should i look

 

High Idle speed and Fluctuation troubleshooting

Leaking EACV- Disconnect EACV connector. Idle speed should decrease. With the connector disconnected block the hole in the intake port or pinch the hose from the air cleaner to the EACV. If the idle speed decreases the valve is leaking. This condition will not set a code. The ECM can only detect an open or short circuit. It also may clog it’s screen if it has one.

Leaking IAC- (Idle air control valve) Disconnect IAC connector. Idle speed should decrease. With the connector disconnected, block the hole or pinch the hose to the IAC valve. If the idle speed decreases the valve is leaking. May not set a code and may not be a codeable circuit on all models.

TW or ECT sensor- (engine coolant temperature sensor) voltage should be about 3.0 volts @ 60 deg F and between .55 & .7 volts @ normal operating temp. If the voltage is above .8 volts at normal operating temp, will cause rich mixture and high idle speed. May not set a code because it is not far enough out of its operating parameters. **Also this sensor will not read temperature correctly if coolant is low. (beware)

Vacuum leaks- a loose vacuum hose or leaking intake manifold gasket can cause high idle speed and/or fluctuation. Also check for bad PCV valve.

Fast Idle Valve- (if equipped) a fast idle valve that is sticking can cause high idle speed and fluctuation. Check it by removing the steel cap on the top and putting your finger over the hole in the middle of the seat under the cap or block the port just inside of the throttle body opening, when the Idle is fluctuating or staying high. When the engine is warm this valve should be closed. You can tighten the seat but it will also change the idle speed warm up values (closing).

Throttle valve- throttle position sensor voltage should be .5 volts with the throttle closed. Make sure the throttle valve is fully closed and voltage is within spec.

ECU-If all else is good, if you reset the ECU and the problem goes away temporarily, the ECU may be defective.