1986 240 DL IAC

mhgreen · Post by **mhgreen** » 04 Feb 2015, 16:13

1… how does one test the iAC? I tried testing resistance but I got no reading.

2… does anyone have the bosch part number for the IAC on my car? I am not sure it is even the right one

Matt

lummert · Post by **lummert** » 04 Feb 2015, 20:12

I found two part numbers:

0 280 140 501
0 280 140 520: To Chassis # 334099

93Regina · Post by **93Regina** » 05 Feb 2015, 07:48

mhgreen wrote:2… does anyone have the bosch part number for the IAC on my car?

Second Post Here: 1986 240 DL fluctuating idle

mhgreen · Post by **mhgreen** » 08 Feb 2015, 16:00

So I found an IAC at the jy and replaced mine. Now my idle is unbelievably high. As if the pedal is to the floor. So I put back the one that was on my car, and the idle is still out of control high. Any thoughts? (tps is adjusted correctly).

93Regina · Post by **93Regina** » 08 Feb 2015, 19:34

mhgreen wrote:idle is still out of control high

With engine warm, and turned off, disconnect IAC's electrical plug...then fire it up.

mhgreen · Post by **mhgreen** » 08 Feb 2015, 19:58

93Regina wrote:
With engine warm, and turned off, disconnect IAC's electrical plug...then fire it up.

Idles much better

mhgreen · Post by **mhgreen** » 08 Feb 2015, 20:01

Should I be concerned with the ECU??

93Regina · Post by **93Regina** » 09 Feb 2015, 07:23

mhgreen wrote:Should I be concerned with the ECU??

See how it goes....one can always re-plug it back in, after cleaning off terminals with electrical contact cleaner.

mhgreen · Post by **mhgreen** » 09 Feb 2015, 10:47

So since it runs fine unplugged what's the motivation to plug it back in?

93Regina · Post by **93Regina** » 09 Feb 2015, 11:57

mhgreen wrote:...what's the motivation to plug it back in?

Intake Manifold - Thou shalt not allow additional atmospheric air into intake system, other than what OEM-throttle-body's specification allows for, and what OEM's specification for IAC allows for. It is absolutely forbidden to have leaking attached vacuum hoses, leaking intake manifold gasket, and/or to allow a defective brake booster's diaphragm to pass atmospheric into intake manifold.

In warmer climates, an unplugged IAC may not be an issue.

Thus, if your throttle plate/switch is not set to OEM's spec, if defective sensor readings exist, and if air leaks flow into intake manifold, this screws the Bosch LH system.

IAC function is to regulate idle speed; it either reduces or increases additional air to intake. On LH2.4, it also operates during driving cycle...it may or may not be the same on yours...most likely emission related.