Impreza Wont Idle
 

Hi All,

I was reversing my v4 type out of the shed a few weeks back and it started to run lumpy and would not idle.

My fuel gauge was low so I assumed it ran out of petrol.

I put about 20 litres into her last night and again the same issue.

It can misfire, backfire and cut out.

Eventually if you do get to start her and rev it to 3-4k and it avoids stalling once its warm it runs ok.

The temp gauge is also erratic.

It has an obd2 port, which ive tried a launch system and the torque pro app, neither could connect to the ecu.

It's almost like an ignition problem, new plugs were fitted, ht leads tested o.k , no loose earths.

I'm wondering those the temp gauge effect the ecu's cold performance?

Normally I suggest the CTS, but Im unsure if yours is a 4 pin one that does both ECU temp and dash temp gauge.

Its V4 Type R, so im not sure if it has two separate gauges, guessing it doesn't as The dash gauge is erratic also.

Apparently upto and including V4
https://i.ebayimg.com/images/g/uNMAA...en2/s-l300.jpg

https://a.d-cd.net/e836a14s-480.jpg

http://www.kantuo.com/web1/UploadPho...6300336949.jpg

Might aswell replace the two if I have to drain the coolant.

Just ordered the two from ICP

Ok so I got my brother to send on a video of my codes ( flashing check light )

22- Knock Sensor
23- MAF
31- Throttle Position Sensor
45- Pressure Switch

I'm guessing all these can't have gone at once, so whats most likley pegging off the rest of the codes?

reset the ecu, then drive the car and check what codes have come back.

O.k so the ecu was reset.

Code 23 and 45 remain.

The Maf has approx 1v at idle and went upto about 5v ish volts at 5-6k rpm.

Before the engine flooded itself and cut out.

Also resulting in a puff of fumes back out my intake.

I've cleaned the idle control valve, its o.k

Checked TPS resistance .7v closed tp 5v approx open

Starting to think a tooth might have jumped on the timing belt.

As there was no gradual symptoms, the car was running fine and then started out of now where to have these symptoms.

I have two temperature sensors coming so I might as well change them now that there bought.

I'm going to look into the pressure switch before I order anything else

Unplug the MAF and start the car and see how the car idles. If it idles OK, its running off default value in ECU and you'll know MAF is fooked.

Has there been any coolant leaks ? They can hunt and have a dodgy idle if there is trapped air in the system, so check levels or try 'bleeding' system too. Especially if your saying the gauge has been erratic this would make sense.

Engine runs the same with maf plugged in or out. No coolant leaks either

Basically the car is un drive able at the moment, it wont idle.

So that leaves code 45 pressure switch, would this cause the running issues?

Has this only happened since you changed the spark plugs ? We're the plugs gapped correctly before fitting ? Also check coilpack for any hairline cracks too. Does the car drive OK apart from idle, or does it misfire when driving etc
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What pressure sensor are you speaking about ?

It was all fine until a few weeks ago, as I was reversing it out of the garage it cut out and started acting up.

Assumed it was out of petrol at the time because the light was on.

Coilpacks look fine on visual inspection, leads are also fine, new plugs fitted a few months back.

Tbh I havent looked into code 45 pressure switch yet,so not sure what the sensor actually is

This may give you some idea
http://clarkdh.net23.net/NTL/Code45-1.jpg
http://clarkdh.net23.net/NTL/Code45-2.jpg
http://clarkdh.net23.net/NTL/Code45-3.jpg
http://clarkdh.net23.net/NTL/Code45-4.jpg

Pressure Sources Switching Solenoid valve - item 7 below

http://static.opposedforces.com/epc_...1494808102.png
http://opposedforces.com/parts/impre...llustration_2/

Thanks, wont get to check it until the weekend.


So would problem arising from code 45 cause such running issues?