Engine Coolant Temperature Sensor

[cyberfella]

Pulled an error code 21 out today. It would appear that I need an engine coolant temperature sensor. I've trawled the net and found copious amounts of info about the knock-on affects of a faulty coolant temp sensor, but I can't find anyone who can supply one (apart from subaru but my car's an import). :action-smiley-060:

Any ideas where I might be able to buy one?

[beachsleeper]

Try here
http://www.gradea-subaru.co.uk/

Best to phone them. :action-smiley-065:

[cyberfella]

Try here
http://www.gradea-subaru.co.uk/

Best to phone them. :action-smiley-065:
aahh, thank goodness. Beachsleeper to the rescue. Cheers mate. I'll phone them tomorrow. :sign0191:

I've just found a threaded sender and braided line all gathered up and zip-tied, which is connected to a clear (yellowish) cylindrical plug with two wires coming out of it. Located around the boost control solenoid and maf sensor area on the drivers side of the engine bay. It was just floating about?? what is it? it's not the bloody engine coolant temperature sensor is it?! Hang on a minute, I think it's the lambda sensor from my old downpipe. Doesn't this ideally need to be fitted to my new downpipe?

[Neil G]

Could be the egt sensor

I ran my WRX without this plugged in but you should definately have a lambda sensor in the pipe somewhere....I'd be surprised if there wasn't one.

[cyberfella]

After some extensive searching, I finally found the engine coolant temp sensor and by some miracle managed to replace it myself.

FYI peeps, both the gauge sender and the temp sensor sit right next to one another on an alloy pipe that runs between the block and the manifold. You get to them by disconnecting the induction pipe to the turbo and all the bendy pipes around there and moving them out of the way. This leaves a hand-sized gap for you to get your right hand down to disconnect the plug, then after loosening the sender with a 19mm spanner, use your left hand to unscrew it. you'll feel the engine coolant run out (so don't do this on a hot car, leave it at least an hour to cool down so you dont burn yourself).

Space is tight, you can't see what you're doing so do it in plenty of daylight and use your left hand/right hand as described above and you'll swear a lot less. Close your eyes and feel your way around, don't bother trying to see what you're doing.

When it comes to putting the new one in, add a bit of grease to the copper washer to help prevent loosing it as you reach back down to screw the new one in. Tighten it with the 19mm spanner, then swap hands again to plug in the plug. Re-fit all your bendy pipework and tighten the jubilee clip around the turbo pipe. Top up your lost coolant to finish. You'll instantly feel smoother running at low rpm.

[cyberfella]

I spent two hours with Alan Jeffery this morning on his Dyno Dynamics rolling road, trying to figure out why my car is still running lean.

Everything seemed fine. I had fitted a new fuel filter, and an inline fuel pressure gauge and fuel pressure at idle was fine at 2.2bar. It rose as it should under acceleration. Yet the AFR curve was still lean up in the 14's

We tried three MAF sensors (two of mine and one of AJ's) and the car richened up as it should when the air filter was off but as soon as it went back on, it stayed lean??!!

Conclusion. The induction kit I was using was flowing air along the walls of the pipe but not in the centre leaving the hot wire in the eye of the hurricane as-it-were blissfully unaware of how much air was flowing. subsequently, the ecu didn't know to add more fuel. Ouch.

All sorted now though, with different induction kit that retains central air flow so the curve is as it should be running richer and richer the more hammer you give it, in order to protect the engine.

I'd urge anyone who has modded their induction kit to book some time with AJ to check your car is running right. Forget the pretty pictures on the boxes and the empty claims of more power etc, your car maybe badly affected by the induction kit to the point where your engine could ultimately fail.

Alan Jeffery has the necessary equipment and expertise to thoroughly diagnose the running of your car, so use him. It's money well spent. Considering we weren't remapping an ECU, just using the rolling road for diagnostics purposes, I still left there with a safer running engine, a power increase and tremendous power and torque gains in the low to mid RPM range. It honestly feels like a different car now, much smoother at low rpm with no stumble as before.

Big thanks to Alan for spending the time with me this morning. It is much appreciated matey!

Evidence for those who love dyno graphs ;o) Note: before (red) and after (blue). A visit well worth while, yes?!

http://cyberfella.redirectme.net/Dyno_Dynamics_Diagnostics.jpg