Hey,

Just bought my first 7 today, it's a series 4 with series 5 engine and guts.

I noticed that sometimes when I pull up at the lights the engine idles at 1500rpm, but other times it idles at around 800...

If it's at 1500 and I switch the engine off, then back on it settles back down to 800 rpm :S

SO I'm not sure what could be causing this and it would be great if someone could shed some light

BTW air-con was off the entire time.

Cheers,

- Luke

 

I get this too sometimes, depending what rpm I push in the clutch to come to a stop. It's usually in the 2-3k rpm range. I think the roller on the fast idle is getting stuck.

 

What is this roller you speak of :P ? and where can I find it

 

Depends. You got a n/a or a t2?

 

T2

 

I get this sometimes except the highest it hits is maybe 1500RPM. I also have a broken roller thing on my TB ('87 TII), not sure if that's the fast idle roller. I also have my throttle cable set pretty tight though. If I move the pedal ~2mm I'll usually bump up several hundred RPM (at idle), and I think the return spring isn't pulling hard enough at full closed to overcome the friction in the cable casing.

 

Hmmm so can I access this roller by taking off the TMIC? I'd like to have a tink with it... cannot stand this high idle

I couldn't find any detailed methods in the manual...

 

Funny. When I had a problem with fast idle, I couldn't find another but pictures of t2 TBs. And now I can't find anything but N/A TBs. lol. I'll try and find something for you.

 

Cheers, if you can find something that would be great m8!

I emailed the previous owner of the car who is also a rotary engine vehicle specialist and he said:

"Hey dude, yeh the idle does change between about 1300 and 850rpm. I've tried allsorts of things and cannot get it to stay constant. I spoke to my boss Jason about it, and he said its just to do with the standard computer, and he's had heaps of cars and theres not much you can do about it. Sometimes it goes onto a different map. It never really posed a problem, so It didn't bother me too much. If you fit an aftermarket computer (power fc, Microtech), you won't have a problem."

!!!

 

Could it be; the ecu is acting up because the emissions gear has been removed?

 

removing "emissions gear," depending on what actually was removed, usually lowers the idle.

first thing you need to do is check your TPS. do a search on that... I think it's in the FAQ too? Then remove your throttlebody and follow the procedure in the factory service manual for adjusting the fast idle system if. There are a couple of screws that a previous owner may have messed up. You can clean your BAC valve. Also make sure that your auxilary port actuators are opening and closing smoothly. I had one stick open before (just one though, not both) and for some reason it affected my idle.

 

My 87 t2 is doing this right now. If i use the tip of my shoe to pull up on the throttle pedal, then my idle goes back to normal.

As soon as I get the damn turbo back on it im going to try and see if its the cable sticking or the trottlebody's springs/rollers/etc.

 

Yeh I tried that - pulling the throttle pedal backwards but it had no effect for me!

 

^^ guaranteed that you have a sticking throttle or cruise control cable