Hi everyone

New to RX7 and new problem occured all of a sudden.

With warm engine my car has quite high idle - around 2000-2300 RPM
This is new problem, because it was allright few weeks ago.

My car was idling rough so changed spark plugs, wires, I have cleaned IAC valve with carb cleaner as well. Not sure what might cause thise problem or it's just coincidence.

Any suggestions what to look for will be helpful
Thank - Mike

 

Hi mike,

strange that it came on all of a sudden. Things I'd look for is any vaccume leaks, usually causes the idle to hunt (bounce up and down) but they have also been known to cause high idle.

check your throttle cable has a bit of slack in it, also check that the throttle body is not stuck open which I've actually had happen to me a few times, the spring mechanism with age can become stiff and not allow the throttle to close fully.

If those check out see see if you can get hold of a new ICV to try incase yours is faulty. I'm sure some more experienced members on here will message soon with more troubleshooting to try.

 

thanks a lot!
i will check those things tommorow and let you all know.
Any more suggestions are welcome.

Thanks

 

i mean you cleaned the iac so it would kind of make sense why the idle would change. adjust idle and listen for hesitation, bogging, and popping. if you can get your hands on a sniffer you can be way more precise. good luck and if ya can send more symptoms.

 

Hi again

Today I've noticed that one vacum hose is missing (behind engine, near firewall, below IAC valve). I'm not sure if I bought car without it or it fell off by accident while I was cleaning IAC valve... On the photo you can see 3 vacum pipes and one (middle one) is missing.

Can this be cause of high idle (2000-2200 rpm)? Ofcourse I'll replace it - should it be connected to the manifold?

 

Seems you're referring to the fuel lines and the open one is the evaporation line. It can be removed as a part of emission stuff and I don't think it can affect the idle at all...

 

Think they connect to the UIM. If the UIM is not blocked, you have a vacuum leak.

https://www.rx7club.com/3rd-generati...-turbo-749702/

 

Friends
I've checked nipple under UIM and it's blocked.
I have JDM engine so maybe someone made some modifications before with this.

I have to go deeper with searching problem

 

sounds like a vacuum leak

 

Today is a new day.
Maybe it's better if I tell the whole story. When I bought my RX7 it was having such issues:
- cold start RPM=800-900
- rough idle
- stalls when switching lights ON or switching gear from P/N to D (yes it's auto)

I put new spark plugs and wires. I cleaned IAC. After that cold start=1500-1800 RPM and when warm idle was 2000-2200.
Today I've cleaned IAC again, controllet throttle body, touched this and that and my high idle dissappeared but first problem occured again. Cold start - 800, rough idle when cold, engine stalls when changing gears or turning lights on.

I think it's not vacuum leak because or new problems.
Can this be IAC? TPS?

I really need help with this..

 

Hmmmm,

The fact the car stalls when turning the lights on is very bizarre, maybe a wiring issue?

i would try a new ICV, incase yours is faulty.... also make sure the TPS voltages are in spec. Are you on factory ecu or aftermarket?

 

Stock ECU

Hmmmmm I thought of wiring issue as well but don't know how to check it.
Battery is new, I checked few grounding points.

I think it's might be not connected to the wiring problem but to general load to the car.

IF I unplug IAC should it be any different how engine works????

 

test the voltage of the alternator to see if it's outputting correctly. Should be between 13.8-14.1v.

if your car is a USDM spec car not JDM you'll have the AWS system that came with the car, this could be the fault. Plenty of info on this forum about it, just have a search. Still think you should try a new ICV....or grab the FSM and test the voltages as stipulated there. I am putting my money on the ICV AWS or something between the throttlebody and uim isn't right.