Well anyway I've actually gotten to spend some time working on my GSL-SE today. I got it a few months ago and havent had time to try to make it run right. I got it to start (the guy I bought it from couldnt even get it to do that, +1 me) but it wouldn't idle, it made plenty of power and went up and down the road, it just wouldn't idle. Well tonight I got it to idle, sort of... First thing I did tonight was a compression test. When I first got it pulling the rear leading plug would get me two strong and one soft pop, after some atf and hard driving I got three strong out of it.
I did a compression test with a normal tester with the valve out of it and seemed to get good results. spikes over 80psi, so it seems good to me. So I adjusted the TPS via the write-up, took off the BAV and cleaned it, cleaned the throttle plate, checked alot of the vaccum lines, changed cap and rotor, and still no idle.
The thing is, it wouldn't even try to idle, if I rev it the rpm falls smooth until about 2k where it's like the key gets turned off. I can get it down low if I play with the throttle but it falls on it's face at about 1.5k.
I started it and let it run for about 10min (foot on gas, 2k rpm) until it was fairly warm. I let off the throttle and it sorta idled! about 1000 to 1200 rpm back and forth but it idled! If I reved it up slowly and let off the gas slowly it catch itself and idle but if I stabbed it it would fall on it's face at 2k and die.
Whats the deal? I'm thinking that its somewhat related to the cold start enrichment but maybe not? The thing is that is kinda idled like it has a bad seal (like a cammed v8 sorta) which confuses and pisses me off. the rotors sound like the have three good compressions and the compression was reading strong, but maybe I'm reading it wrong (I dont how steady the 80 psi spikes are). does this sound like a seal? I'm going to post some short videos tommorrow night of it idling/ reving and of the compression tester. Thanks guy

Sorry for the book

 

BAV=BAC thats what i meant

 

Sounds like the motor is fine and you have some fuel problem.

First thing to do with any sort of funky problem on GSL-SE is check your MAF and TPS sensors. I bet you have a bad MAF. Maybe they are both bad.

Cold start enrichment could be a factor but it is seriously hard to start it at all if that isn't working plus once it is warmed up it will run fine... so if it dies when you stab throttle there is more to it than cold start enrichment. Although it could be bad too!

 

And by "MAF" I actually mean "AFM". You probably figured it out.

 

how do I check the AFM and TPS? I know that I have the TPS adjusted right. I'm getting a video of it idling and of the compression test soon

 

http://media.putfile.com/RX7-Compression-Test


This is the compression test on the rear rotor, 80psi is about 10 o'clock on the gauge


http://media.putfile.com/Leading-Plu...rear-rotor-RX7

this is what it sounds like with the leading plug pulled on the rear rotor, I didnt pull the EGI fuse



http://media.putfile.com/warmed-up-idle-rx7

this is the car's idle once it is warmed up, does it seem like I have a blown seal?

 

http://media.putfile.com/cold-idle-rx7



this is the engine revving and trying to idle when it's cold (actually ran like 5min but the gauge hadn't moved). Shows how it doesn't even try to idle, I'm holding it at 2k and then let go

 

So whats up? do you guys think that its a blown seal? pr could it the afm or something?

 

in the haynes or fsm it shows how to test the bac and tps, afm is a little more complicated.
easy test for the bac is to put power directly to it and listen for the solinoid to click.

your problem could be a vacuum leak as well.

 

doesn't the idle sound like a blown seal though?

 

I'm sure you've tried removing the old gas if any sat in it and changing the fuel filter? Also I'm sure the oil is okay?
I had to do an oil change, run seafoam, and change the fuel filter for it to start idling right. After putting new gas and a quart of oil in my SE started idling at least.

 

I haven't changed the oil, but I did drain the gas. I wouldnt think that the fuel filter has anything to do with it. I runs better the higher its revved. Does the compression test look right? it almost seems like two strong one weak to me

 

I thought it was supposed to be six chug or pssssh noises or whatever. Everyone describes it differently.
Is the oil level okay?
How long did it sit?

 

could someone in the know please watch my compression test and idle videos, I need to drive down and work on it today and I'd like to see what you guys have to say

 

it wont let me watch them.
if you let the compression build up what is the psi on the suspected bad rotor?

 

GSL-SEs' have a problem with Idle. There is a great FAQ anwsering how to fix it.

(FAQ) https://www.rx7club.com/1st-generation-specific-1979-1985-18/1st-gen-rx-7-faq-page-237777/

(Just some of Idle under FAQ).

http://mrmazda.no-ip.com/gslseidle.html

https://www.rx7club.com/showthread.p...hreadid=235009

Scroll down untill you see

Q. My GSL-SE has idle and surging problems, how can I fix it?

Hope the best

-nick-

 

I'm at work so I can't view the videos. Damn office filters!

 

do you realize your supposed to do compression tests out of the trailing plug with the engine warm.

add one more part to the list that could be potentially bad, that is the variable resister, the thing with the screw in it that is used to adjust the idle mixture.

 

I did do it with engine cold but I thought that it was on the bottom, leading plug? I haven't tried to let the compression build as I did it with the valve out of the tester. I went through that FAQ already, I cleaned the BAV as well as some other things. The reason why I want someone to at least watch the idle video is that the car has a rough idle, like a cammed v8 and I thought that I heard somewhere that that is the way that a blown apex seal sounds. Thanks for all the help guys, I'll check the AFM. Know any good tricks for finding a vacuum leak?

 

what should the compression build to if I were to keep the valve in?

 

Have you bought new sparkplug wires and spark plugs?


My compression goes to about 85 on the gauge on the rear and 95 on the front. Anywhere up in those numbers is fine.

 

new plugs and I;ve cleaned them a few times as I've worked on it. I'm going home now to pull the exhaust manifold off to check the apex seals to take the question out of it

 

It doesn't matter what the compression builds to if you leave the valve closed... it will give you some number but it doesn't mean anything.

If the only concern is "blown/not blown" take a plug out, disconnect the ignition or pull the engine fuse, take one plug out of each rotor and crank the motor. If it goes "CHUFF CHUFF CHUFF" it is fine. If it goes "CHUFF piff piff" it is dead, or at least, very unhappy. Let it crank for 10-15 seconds since a lot of times it doesn't get full compression right away... which is ok.

The main point of a full compression test is to check how worn the seals are (how much life left in the motor), or to get hard numbers.

 

Im downloading the video now of cold idle.

-nick-

 

I know about the compression, some one asked what it would build to, I did the test with the valve out. I have a video on the first page of it turning over with the plug out and I'm not sure if it's three strong or one weak two strong