GZE swap, running rich and problems with idol. - Page 2

HoLun · 02-13-2009, 03:56 PM

you can hook up the vacuum gauge to direct manifold vacuum, you can tee into any vacuum lines going into the manifold

IMO resistance test is only good for testing continuity, heat and other factors in the circuit can change resistance, and you will not be able to test the entire circuit with a ohm test, a component might test good and still not function correctly. you will miss a lot of things by only using resistance test, voltage and voltage drop test will be the way to go.
tho resistance test have its place, make sure you test the component with it out of the circuit, not connected to anything, not powered. you can fry your meter, or the ECU if its connected and/or powered.

I bet most electronics made in the 80s will still be working great today if people don't go and buy newer stuff. you don't see them because technology changes so fast and people always want better, faster, newer things.

so no reason not to trust your 20 year old ECU if it has been in a car thats well kept.

Krimzen · 02-14-2009, 04:29 AM

Now I did not realize there were other screws on the IAC that changes the idol. I have been messing, and messing, and messing with that screw and have not had too much flexibility with the idol. Bringing the idol down could drastically change the way the engine is running! I have never really heard the car idol at that range since I first started the engine. So yeah, I agree, there may be light at the end of the tunnel.

As for the Cams. I do not think the a mis-time of the cams, like a tooth or two, would make the idol reverberate like it does. I have Adjustables on them set at zero along with a double check on the engine timing. I agree, they are probably not set right, however I believe that will after I get the idol to calm down and relax.

I am not ruling it out completely. First and foremost......

What is actually happening when the idol does that when there are no coolant bubbles in the system.????

HoLun · 02-14-2009, 10:38 AM

Quote:

Originally Posted by Krimzen

What is actually happening when the idol does that when there are no coolant bubbles in the system.????

Bouncing idle after engine warm up, in closed loop, if the cooling system is bleed properly, this can be cause by over/under fueling or bad o2 sensor, and the engine is trying to compensate from the o2 sensor reading.

can also be from reversion caused by aggressive cams, causing the afm door move back and forth rapidly. can also apply to map sensor if its a speed density system where the pressure reading change rapidly.

so whats you manifold vacuum reading? also is the reading smooth or abrupt?

Krimzen · 02-17-2009, 12:57 PM

Quote:

Originally Posted by Papo J

None of those mods are radical enough to render the ECU unable to control the operation of the engine. To me it sounds like there is too much overlap dialed into the cam timing and you may need to play with them and adjust them properly, the 0 mark on the stock gears is no longer good enough for higher duration cams, it will still have overlap because of the longer duration and the extra time needed for the valves to fully close. Make sure that the 2 water lines under the TB are connected and also make sure the timing is set correctly, both can affect idle after warmup.

The cams were my first notion. As long as I have a seal on all of my gaskets, and I put my fuel pressure at 38, and my car is timed and double checked at zero. My cams are the only thing that I physically changed.

Where can I find out how to time the new cams with adj. gears? HKS states to first set it at zero.

4AGTE · 02-19-2009, 12:56 AM

Hi, I live in atlanta. I'm pretty knowledgeable on MR2 swaps and diagnosing problems. If you want, we can meet and I'll help you figure out the problems. Make sure the TPS is calibrated right, check it again? That is one of the most common culprit for fluctuating idle. If your car has power top end, it's probably not the knock sensor. Stop messing with the fuel, it's not where the problem is. Take out a spark plug to inspect it if it will ease your mind. If your timing is too advanced, it will cause high idle. If you have already bled the coolant for the 5th time, stop thinking it's the coolant.. the SC has the ISC to control idle. NA uses a special wax in the throttle body that needs the coolant to melt and lower idle as the temp rises. I'd suspect it has something to do with timing the cams or TPS miscalibration.

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02-13-2009, 03:56 PM	#21 (permalink)
HoLun ASE Master tech Join Date: Jan 2009 Location: Austin, TX Posts: 79 Thanks: 0 Thanked 5 Times in 5 Posts iTrader Rating: (0/0% )	you can hook up the vacuum gauge to direct manifold vacuum, you can tee into any vacuum lines going into the manifold IMO resistance test is only good for testing continuity, heat and other factors in the circuit can change resistance, and you will not be able to test the entire circuit with a ohm test, a component might test good and still not function correctly. you will miss a lot of things by only using resistance test, voltage and voltage drop test will be the way to go. tho resistance test have its place, make sure you test the component with it out of the circuit, not connected to anything, not powered. you can fry your meter, or the ECU if its connected and/or powered. I bet most electronics made in the 80s will still be working great today if people don't go and buy newer stuff. you don't see them because technology changes so fast and people always want better, faster, newer things. so no reason not to trust your 20 year old ECU if it has been in a car thats well kept.

02-14-2009, 04:29 AM	#22 (permalink)
Krimzen No Skills Join Date: May 2005 Location: Marietta, GA Posts: 65 Thanks: 8 Thanked 3 Times in 3 Posts iTrader Rating: (0/0% )	Now I did not realize there were other screws on the IAC that changes the idol. I have been messing, and messing, and messing with that screw and have not had too much flexibility with the idol. Bringing the idol down could drastically change the way the engine is running! I have never really heard the car idol at that range since I first started the engine. So yeah, I agree, there may be light at the end of the tunnel. As for the Cams. I do not think the a mis-time of the cams, like a tooth or two, would make the idol reverberate like it does. I have Adjustables on them set at zero along with a double check on the engine timing. I agree, they are probably not set right, however I believe that will after I get the idol to calm down and relax. I am not ruling it out completely. First and foremost...... What is actually happening when the idol does that when there are no coolant bubbles in the system.????

02-19-2009, 12:56 AM	#25 (permalink)
4AGTE Some Skills Join Date: Mar 2007 Posts: 53 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (2/75% )	Hi, I live in atlanta. I'm pretty knowledgeable on MR2 swaps and diagnosing problems. If you want, we can meet and I'll help you figure out the problems. Make sure the TPS is calibrated right, check it again? That is one of the most common culprit for fluctuating idle. If your car has power top end, it's probably not the knock sensor. Stop messing with the fuel, it's not where the problem is. Take out a spark plug to inspect it if it will ease your mind. If your timing is too advanced, it will cause high idle. If you have already bled the coolant for the 5th time, stop thinking it's the coolant.. the SC has the ISC to control idle. NA uses a special wax in the throttle body that needs the coolant to melt and lower idle as the temp rises. I'd suspect it has something to do with timing the cams or TPS miscalibration.