1989-1990 Ka24e Idle Fluctuation

[ledzeppelin240]

I was checking out TSB and came accross this. Bulletin No.:NTB91-022.

Condition & Cause
Some 1989-90 240SX vehicles may experience idle fluctuation when coming to a stop (warm engine) or after a warm restart. This condition applies to the flooiwing 240SX vehicles. All 1989-90 California vehicles, and all Federal vehicles built prior to June 8, 1990 and prior to the following VINs:

Federal VINs:
Coupe - JN1HS34P_LW 1090709
Fastback - JN1HS36P_LW 153129

California VINs:
All 89-90

If everything checks out ok and self diagnosis indicates code 55(normal operation)in mode III, replace the ECU with the new part.


Manual Trans 2371M-42F08RE
Auto Trans 2371M-42F66RE


Manual Trans 2371M-40F08RE
Auto Trans 2371M-40F68RE

I am not sure on the prices but this could be a missing link in the idle fluctuation problem.

-chris

[idlafie]

My 95 on occasion will do that...idle will flutter while stopped. Usually it's due to carbon buildup in the Idle Air Control Valve & soleniod located on the back of the engine by the passenger side. A can of carburator cleaner usually solves the problem. It's a hell of a lot cheaper than going out & replacing the ECU.
ID

[ledzeppelin240]

This is after everything has checked out. You should also not be using car cleaner on a fuel injected engine. There are special cleaners that are O2 sensor safe.

[idlafie]

You should also not be using car cleaner on a fuel injected engine. There are special cleaners that are O2 sensor safe.

You shouldn't be using carb cleaner on a fuel injected engine but you can. However, caution should be used prior to using it..some of the newer model cars on the market today have intake manifolds and throttle plates that are specially coated with a film that helps prevent carbon buildup on the intake manifold & throttle plate. Using regular carb cleaner will remove that coating and damage the intake manifold & throttle plate. Fortunately the 240sx' intake manifold & throttle plate don't have the coating so using a carb cleaner is okay.

Carb cleaners are oxygen sensor safe. If you check the required government material safety data sheet all manufactures are supposed to submit for their chemical products, you'll find that carburator cleaners are nothing more that a mixture of propane, toluene, methyl alcohol, acetone & diacetone alcohol,
(http://www.herc.org/library/msds/carbcleaner.htm) - Stuff already currently found in gasoline products & fuel additives. Just make sure you read the label on the can of carburator cleaner that you are about to use & confirm that it is safe to use on catalytic converters and emission related items. Most on the market are.

Anyhow, hope this clarifies any confusion....

ID

[jdm538]

my car does this where is this can i see a pic? also do i have to unbolt anything i really need to do this.. thanks..

[ledzeppelin240]

First of all do you have an 89 or 90 240sx? Next have you ckecked EVERYTHING out? It could be something like new spark plugs and rotor to fix it. More info is needed...