All of the stock Idle controls on my car have been blocked off. When you first start the car it will idle nicely at 750rpm if warm but once you rev it it likes to stay around 1000 rpm. I thought it may be a problem with the throttle cable but it appears to have a fair amount of slack in it. Also if you put it in gear and slow the engine with the clutch it will idle back down to 750 rpm. I need help on this one

 

check the adjustment on your dashpot. It's the piece that helps to keep the throttle plates from snapping shut all at once. You might need to adjust it so it doesn't "help" as much.

just a thought. . .

Reese

 

I was thinking that reese...also what if I just removed it all together? We did it to a friends and the slamming shut of the throttle plates made his car flame really well.

 

Its not the dash pot and I dont think it has anything to do with the position of the throttle plates. I think it has something to do with the timing sticking to advanced, the mixture changing or something like that. Any thoughts?

 

sounds like this is the same problem as mine but they didnt get a definite reply

https://www.rx7club.com/forum/showth...e+changes+1000

 

grr need help

 

TPS okay?

 

not the tps

 

If its on your GTU there should be a Adjustment screw on the top of the intake manifold directly in the center.

If it's on your TII then the only way I've found is to adjust the throtle cable. I did it without removing the intercooler.

 

I dont have a problem setting the idle I have a problem with it "picking" a higher idle once I rev it

 

forget what I said. I just read your post a little more closely

 

AFM okay? Have you lubed the linkages around the UIM? How about the thermowax?

Just throwing ideas out, here.

 

The AFM reads .4% air flow even when its off according to the SAFC I swapped SAFCs and the other one did it too so I assume thats normal and I tested it a while ago... It really appears to be electrical everything moves smoothly

 

bump

 

I'll be watching this thred closely.
Mine does the EXACT same thing.
Except, it's "high" idle is 1200rpm and it's "normal" low idle is 800 rpm?
My car is completly stock, No mods at all.
It's strange?
Somebody out there must know what this is?

 

bump

 

https://www.rx7club.com/forum/showth...light=test+afm

Do you have a copy of the FSM? You can dl a scanned 1988 RX-7 one from www.iluvmyrx7.com

They mention a good idea in that thread - have you checked for error codes yet?

 

It annoys me when people DONT check the error codes...so yes I have I check the AFM when it was doing this a while back. Its done it about as long as Ive owned the car.

 

Check this out:

https://www.rx7club.com/forum/showth...hreadid=141018

It's not the exact same problem as you, but there are some good ideas in there. At the very least it'll keep your hands busy.

 

You get 750 rpm at start up, and then every time you're at idle after that, you get 1,100 rpm, or is it kinda random ?

Can you try the following:

Get the voltage at the TPS

Do you see a difference in voltage between your idle at 7500 and when it is at 1,100 rpm

If you see a noticeable difference,
either the TPS is bad or the throttle plates are not coming at the same position at rest.

Hugues -

 

When you set the idle, did you remember to jumper the "initial set coupler"?

Also when you set the TPS, was the car fully warm or cold? Should be warm.

Is your timing set?

I've had this problem on my 86. It would idle at 1000-1100 RPM after I reved the engine. Loading the engine with the clutch would return it to 750. Also, if I turned on the blower fan, or headlights, or rear defogger then turned off again, the idle would drop back to 750.

I set the timing, then the idle (while the initial set coupler was jumpered) and it's fixed.

 

COsborne - You said the idle controls were all removed.
Was the BAC removed also?

 

When I went there I followed a link hailers posted...this might be helpful Im going to go test the thermo sensor...the idea of it being bad has crossed my mind a few times

https://www.rx7club.com/forum/showth...ter+and+thermo

 

the bac has been removed and I always use the initial set coupler... I never notice a difference though b/c I believe it only controls the BAC which I dont have. I'll have to check the tps voltage. It seems to keep "working" its way out of adjustment though. Maybe something is loose in the throttle body. It doesnt seem like it is though. I dont have thermowax but always make all of my adjustments while fully warm. Also it has some trouble starting. I have to cut fuel to start it when hot and it runs like **** when I start it in the morning. Floods horribly. I disconnected the thermo sensor and it made it start right up but it would die immediately after...maybe b/c its telling the computer its 80 degrees celcius when it was covered in ice from yesterday's snow drifting I have to go get my hair cut but when I come back Im not resting until we solve this damn thing! I know too many other people with the same problem.

 

This weekend I swapped the throttle body and checked ALL the linkage. I even took it apart to check it all for sure. I didnt get any better results with my hot start problem OR the idle thing. All thats left to check are the Injectors and 5th gear switch/neutral switch. Anyone have any thoughts on that?