Collective Experts:

 

95 Impreza, 120K miles, never a hiccup! Now CEL is on hard, with errors

56, 21 and 23. It is very slow to warm up... barely runs for first minute

or so... then fairly normal except radiator fan is on all the time.

 

So it sounds EGR related. I don't get #34, the EGR solenoid failure which would have been my guess.

 

So, switching from math & science to lore, which will be much more powerful

fixing this one!

 

Thanks for any suggestions. Bill Hale, Loveland CO

I'd reset the ECU, and see what codes come back. However your warm up symptoms would point me towards replacing the coolant temp sensor.

Thanks for the suggestion. I had assumed the EGR was driving the problem,

but maybe it is the coolant sensor. This would be easy to check.

Room temp R?

 

Is the cluster water temp gauge driven by this? It does read correctly.

 

On resetting the ECU: I have a pair of connectors on the memory side but

only one two pin female connector on the left side. Doesn't look like the

documentation. To reset, I must connect both. Do I short the two pins

together on the left side connector? There is nothing else to plug it into.

 

Checking for smoke!

 

In the EGR line, there is what looks like a filter. I can't find it on anyones

parts list. What is is properly called? About 2 1/2 in diameter and 2" long.

Seems maybe it should be replaced.

 

Thanks for the consel. I hope I can return the favor sometime. Bill H.

 

 

 

 

Collective Experts:

 

95 Impreza, 120K miles, never a hiccup! Now CEL is on hard, with errors

56, 21 and 23. It is very slow to warm up... barely runs for first minute

or so... then fairly normal except radiator fan is on all the time.

 

So it sounds EGR related. I don't get #34, the EGR solenoid failure which would have been my guess.

 

So, switching from math & science to lore, which will be much more powerful

fixing this one!

 

Thanks for any suggestions. Bill Hale, Loveland CO

I don't know if the 95 impreza is like the first gen legacies. It has two sensors, one for the gauge, and one for the ECU. Even if there's only one sensor, and it reads correctly, it still could be the sensor. They can be cranky, be bad, and still read the correct voltage. You can get them for 20 bucks at www.subarugenuineparts.com So I'd recommend just replacing it....it does wear, so either way, it's a good idea.

 

What color are the connectors?

 

You can also pull the EGI/TCU fuse for 30 minutes or so and accomplish the same thing.

Thanks for the tip on resetting the ECU. I guess I could

just disconnect the battery too.

 

The connector that has no mate has a gray top with two

female blade connectors.

 

Still looking for the coolant temp sensor. I've looked in the

archives and the pix doesn't help. 1.8 engine.

 

Bill H.

Found but not removed ... yet

I'd reset the ECU, and see what codes come back. However your warm up symptoms would point me towards replacing the coolant temp sensor.

 

I should have followed this advice. I replaced the coolant temp sensor

which wasn't as bad as I had guessed. The one I pulled out measured

2K ohms at room temperature, which seemed ok. One of the commentators

suggested that even if they seem OK, they may be flakey, so for Autozone

$25 I get a new one.

 

I reset the ECU and sure enough the codes went away. I've driven about

100 miles and it seems OK. And the cooling fan is off.

 

Trying to learn from this, it would seem resetting the ECU then immediately

checking the codes if the ECU light comes on might help reduce the mulitple

number of codes.

 

As it is, I'm not sure if I fixed this or not... might be a fluke. But who is

to argue with sucess? Thanks for the suggestions. Bill Hale

Welcome. We've run across this numerous times with the coolant temp sensor, which is why I recommend it. It's a cheap part, and can save you a ton of headaches if it is the problem.

Hello, I just caught my intermittent CEL code 56 which is the EGR System. Came across your thread here and was wondering what you thought might be the best place to start? Should I just replace the valve, or is there somewhere else I could start? 

Thank you for your help!