Ok, so over the past week I have been converting my FD to non sequential. As far as mods go, I have Apex intake and a downpipe. I finished like 15 minutes ago (4:15 in the morning) and I was very excited to start my car.

So I go to start it and it starts up fine BUT it revs up to 6000-6500 and makes a weird whining noise (the kind of noise it makes when you have a belt rubbing against plastic) so I freak out and turn it off. After calming down a little, I tried it again, but this time I blipped the throttle and it brought it down to 2000-3000 and it was going up and down irratically between 2-3k. It was still making the noise. I turned it off again and I realized" hey, I forgot to plug in the o2 sensor". So here I am now, I plan to plug it in later in the morning in a few hours. Could the o2 sensor not being plugged in be the reason for the irratic idle?

The car has new oil and coolant, and has the fpr and wastegate directly hooked to the UIM. I took out all the solenoids.

I will plug in the o2 sensor and try again later. Please give me some advice!!!

 

woah wtf, this is actually me, i guess i was logged into someone elses name some how

 

I don't think the 02 sensor would do that..i believe the car would run with it disconnected. You definately wanna recheck the non-seq diagram. I found this to be the most helpful, not sure what you used...

https://www.rx7club.com/showthread.p...nonseq+diagram

 

I'm sure my vacuum hoses are right. I double then triple the quadruple checked them.

I'm going to go try and figure it out. I'll post results in an hour.

 

Ok, I plugged in the o2 sensor and started the car. It fired right up and went to 5000 rpm but i blipped the throttle and it brought it down. It kept going up and down.

The sound was also there. I know no belts are rubbing but thats what it sound like. Someone PLEASE HELP ME!

 

can someone please help me?

 

Well I can't figure out what the noise is so I am just going to take everything apart and put it back together.

Could old intake manifold gaskets cause a really high idle?

 

Did you follow the non seq mod posted somewhere? The LIM gasket should be replaced if you still have the stock paper one. If you have a leak somewhere, your idle will not be correct.

My advice is follow the mod direction again and recheck everything. Also, do a search on the mod to see if anyone has had similar problem. I haven't done it myself so I can't really help you much, sorry.

Sometimes working around the clock doesn't give you a clear head. Get some rest and start fresh again. Good luck.

 

Well the only way for the engine to rev up to say 6000 rpm is for air to somehow get into the intake ports either via the throttle body or a leak somewhere right? And if the throttle body was closed except for the little crack thats always open and it revved to 6k, that must mean there is a leak somewhere right?

I am going to order a new LIM to block gasket and UIM to LIM gasket tomorrow. That SHOULD solve the idle problem correct? If it doesn't, then I don't know WTF to think.

Also, when doing non sequential, you cap off the ACV on the UIM, correct?

But the problem I am really worrying about is the strange griding sound. It really doesnt make any sense to me. I know its not a belt and it's not the airpump because thats not even on... ANY suggestions on where to start on troubleshooting the sound?

 

same things happened to me this week...