home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > maintenance & nonperformance

Reply
 
Thread Tools Display Modes
Old 11-26-2018, 08:37 PM   #1
89_740Turbo
Board Member
 
89_740Turbo's Avatar
 
Join Date: Apr 2018
Location: New Jersey
Default 740 idle issue - how to clean IAC?

How difficult is it to clean the IAC? My 740 has an idle issue which causes it to fluctuate, so I am going to: change the oxygen sensor, clean the throttle body w/ new gasket and looking to clean the IAC. What do I use to clean the IAC and how difficult is it?
__________________
1989 744Ti
1988 744Ti
1986 744GLE (RIP)
89_740Turbo is offline   Reply With Quote
Old 11-26-2018, 09:29 PM   #2
Harlard
Pro Sneaker Peddler
 
Harlard's Avatar
 
Join Date: May 2007
Location: PDX
Default

fill it with brake cleaner and let it soak a few minutes. Then shake the bejeezus out of it until it frees up. You will feel the valve knocking about. Once that happens you can drain it.
__________________


Herr Harlard am Erstens

1979 242 DL

Quote:
Originally Posted by t8fanning View Post
My knob has a big chunk of steel on it
Harlard is offline   Reply With Quote
Old 11-27-2018, 10:14 AM   #3
89_740Turbo
Board Member
 
89_740Turbo's Avatar
 
Join Date: Apr 2018
Location: New Jersey
Default

Thanks!
89_740Turbo is offline   Reply With Quote
Old 11-27-2018, 01:29 PM   #4
DET17
Reformed SAABaholic
 
Join Date: Nov 2009
Location: NW Georgia
Default

Also, be certain your TPS connector has the pins landing on your throttle body. As the female pins are poorly retained in the plug, you can push it into position and it never makes. Without your "throttle closed" confirmation, the IAC will not function.

Permissives, always confirm the permissives.......
__________________
Project "cheap thrills" build thread: http://forums.turbobricks.com/showth...67#post4211467

Feedback thread: http://forums.turbobricks.com/showthread.php?t=198746
DET17 is offline   Reply With Quote
Old 11-27-2018, 02:39 PM   #5
Harlard
Pro Sneaker Peddler
 
Harlard's Avatar
 
Join Date: May 2007
Location: PDX
Default

Easiest way to confirm is to check whether it jumps between 25* and 12* of ignition advance at as close to idle as you can get as you move switch position
Harlard is offline   Reply With Quote
Old 11-28-2018, 07:35 PM   #6
89_740Turbo
Board Member
 
89_740Turbo's Avatar
 
Join Date: Apr 2018
Location: New Jersey
Default

This all sounds risky as hell to me now...
89_740Turbo is offline   Reply With Quote
Old 11-28-2018, 09:53 PM   #7
Harlard
Pro Sneaker Peddler
 
Harlard's Avatar
 
Join Date: May 2007
Location: PDX
Default

Why
Harlard is offline   Reply With Quote
Old 11-28-2018, 10:02 PM   #8
smeha
Tranny Whisperer
 
smeha's Avatar
 
Join Date: Mar 2017
Location: California
Default

I've opened up mine to clean throughly, got new o-ring at local VatoZone and a but of RTV silicone to make sure it doesn't suck air.
Just got a be careful with internals.
__________________
1988 Volvo 245DL (Engine: B230F) (Transmission: AW70) (Fuel Injection: LH 2.2) (Brakes: Non-ABS) (Paint code: 189-2) (Dank memes)
1997 Jeep Cherokee Sport (XJ) (Engine: 4.0L - I6) (2WD)
My Feedback Thread
Quote:
I've been molested by a guy who happened to own 7 and 9 series
<--- Just a dumpster on fire
smeha is offline   Reply With Quote
Old 11-28-2018, 10:29 PM   #9
2turbotoys
Salaminizer
 
2turbotoys's Avatar
 
Join Date: Nov 2007
Location: Reading pa
Default

I just douche the **** outta the IAC with brake cleaner, or MAF cleaner, whichever is closer and wipe it off where you can. Kinda like Harland says. Do that first, if it doesn't work then worry about TPS connections or misbehaving IAC (I just had that problem with an 88 240)
__________________
1979 242 B21 on MS, waiting on L33
1991 740t RIP at 320K, dam rust...
2006 V50 T5 AWD Eurosport Tuning Stage 1 kit, downpipe, intercooler
2turbotoys is offline   Reply With Quote
Old 11-28-2018, 11:25 PM   #10
89_740Turbo
Board Member
 
89_740Turbo's Avatar
 
Join Date: Apr 2018
Location: New Jersey
Default

Quote:
Originally Posted by Harlard View Post
Why
afraid of damaging TPS upon reinstallation
89_740Turbo is offline   Reply With Quote
Old 11-28-2018, 11:54 PM   #11
smeha
Tranny Whisperer
 
smeha's Avatar
 
Join Date: Mar 2017
Location: California
Default

I have high idle when warm issue, definitely not IAC after all tests and all. Going for complete take apart throttle body and replacing TPS. Remind me if I forget to update how did it go.
smeha is offline   Reply With Quote
Old 11-29-2018, 12:44 AM   #12
89_740Turbo
Board Member
 
89_740Turbo's Avatar
 
Join Date: Apr 2018
Location: New Jersey
Default

Quote:
Originally Posted by smeha View Post
I have high idle when warm issue, definitely not IAC after all tests and all. Going for complete take apart throttle body and replacing TPS. Remind me if I forget to update how did it go.
will do

also, very random question but what flange do I use with a 16t turbo?
89_740Turbo is offline   Reply With Quote
Old 11-29-2018, 08:29 PM   #13
Harlard
Pro Sneaker Peddler
 
Harlard's Avatar
 
Join Date: May 2007
Location: PDX
Default

Quote:
Originally Posted by 89_740Turbo View Post
afraid of damaging TPS upon reinstallation
There is no need to remove anything.
Harlard is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 02:04 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.