Greetings all!

 

First, let me introduce myself as this is my first post. My name is mike and i've recently purchased an 88 RX 3 door. I'm no stranger to subarus as i've owned an SVX for quite some time and I work for a subaru dealership. I've had my SVX for about 3.5 years and I'm a moderator over at the svx world network forum (http://www.subaru-svx.net). The RX I got was quite a find. I got it from the original owner and it came with all the service history and even the original window sticker! She took very good care of it and always garaged it!

 

Anyway now I should get to my problem.

 

The car starts right up and revs up as normal. Then after about 5 seconds the rpm's drop quickly, and the car stalls. This can be avoided by pressing the gas pedal. Once the car warms up (must hold the gas pedal down to keep the revs up for about 5 mins, very annoying) the car will idle just fine when you take your foot off the gas. You can drive the car normally then and there are no problems. Once the car sits long enough for the engine to again cool off, the problem returns.

 

My original thought was that it could be the IAC. I removed the IAC valve and cleaned it out with carb cleaner per the advice of a tech at the dealer where I work. This had no effect on the problem.

 

Any help would be GREATLY appreciated. Thanks to all!

 

Mike

How does it start when the engine is already hot? A common problem with these is the coolant temp sensor. My would do the same thing once in a while, but the big thing mine did was flood the engine when trying to start an already hot engine. This is because the computer thinks its cold.

 

Keith

if the engine is already hot, it starts perfectly.

 

Mike

could be fouling the plugs when it is cold, my rally car does that when I first start it, and then once warm it is fine...that's my 2c worth

I'd be checking for small vac leaks, and make sure the IAC is sealed up. My GL-10 had a somewhat similar problem...somewhat. Check the coolant sensor connector, and the IAC connector...another 2 cents worth.

where is the coolant temp sensor located on this engine? I think i see it in the back but im not sure if that's it.

 

Mike

its under just about everything in the back of the maifold. Its right beside the turbo, under some valve thingy with lots o lines on it, and its got a 2 wire connector....does that help? Skip's gota pic...

I removed the rear temp sensor and i think i have a major problem. Shouldnt there be a probe on the end of this sensor that goes into a coolant passage? I think it broke off and is stuck in the hole as I cant see through to any coolant passage and there is no probe on the sensor.

 

What should I do now?

 

Dude, that is the KNOCK sensor, that goes into the block. its a ONE wire sensor. AC current it creates for the computer to retard the timing.

 

You are close tho. Over beside it, on the intake manifold, with a TWO wire connector, is the coolant sensor for the computer. It has a rectagular connector.

 

The coolant temp sensor is more towards the passenger/right side of the engine, again, on the intake manifold...the lower part of it.

wow i feel like an idiot. Sorry that looks totally different from the knock sensors on my svx! back to the garage!

 

Mike

OK - I disconnected the temp sensor. That solved the problem. Although it was hard to start the first time once it was started it idles fine. I would imagine that means it's my temp sensor.

 

Mike

Sounds like it. Too bad I dont have an extra one. TO the yards for you I guess...or NAPA.