My project for last winter was porting/new seals/GT35R turbo/RX7 Store Ultimate Fuel System.

Car started up like I never worked on it, except......

Idle is high, 1350-1650 rpm, then after water temp hits about 160 idle starts to hunt real bad?

Also, when I rev it up a little (about 3-4k rpm) my boost guage doestn move and I dont hear my blow off valve at all. Heck, I dont even hear the turbo spool up?

Any comments????

 

With a big turbo, you might not see boost when free revving it lightly in the driveway. I'd just be patient there.

High idle can ONLY be caused by air getting past the throttle plates. Make sure the throttle cable isn't too tight, you don't have any air leaks after the throttle body, etc. Take a look at recent threads, I just posted a long list of things to look for on a high idle on another thread.

But, with a new motor, just be happy it's starting and running right now. Let the motor get some time on it before you start ironing all the kinks out.

Dale

 

I was very happy that my rebuild started up off the bat. Autometer oil press guage pegged at 100 psi then settles down just a little.

I did alot of work (cutting) on the main engine harness too?????

Could water temp sensor cause this problem? The reason I ask is because it had really brittle wire. Maybe I should take it out and test it?

I am getting ready to check the ISC now and check for air leaks after throttle body.

I am fimiliar w/your name from the club. Thanx for your input. I would appreciate anything else you can think of.

 

do you have the fast idle system on the throttlebody still installed?

 

The Advanced Warm Up System has been gone for years. The high idle is one thing, but the hunting after water temp hits about 160-170 is the thing I am most confused about. I dont know if the water temp is related of coincidenced?

 

KD-93R1,

If you are running the stock PCM, you could look for stored fault codes. Idle hunting could be an IAC or TPS adjustment problem. Also, again if the stock PCM, have you set idle speed when warm with jumper wire between "TEN" and "GND" in the Diagnostic Connector, and with no electrical accessories on? Sometimes if the open-loop setting is far enough off, the PCM will "rail" its capability to hold idle at the desired 720 rpm.

 

I have a Power FC computer.
I am going to check the ISC now and then check for vacum leaks past the throttle plates.

Thanx alot, any more comments much appreciated.

 

The Accelerated Warmup System is not the same as the fast idle system. The accelerated Warmup System is a solenoid controlled by the factory USDM ECU which directs air past the throttle plates. This doesn't even work with a Power FC. The fast idle system holds the throttle plates open until the engine reaches operating temperature.

After you have pressure tested the system I would verify that the AFR isn't too lean (12.5:1 - 13.0:1 is a decent range) and then try to open the air adjusting screw under the TB elbow. Make sure the 4 wires have been cut/depinned per the PFC installation instructions, and make sure "O2 feedback" is OFF under etc. --> function select in the Commander.