Remote location for ECU air temperature sensor

[Shaun_E]

I've seen some people mention mounting the air temp sensor remotely from the air filter back plate in order to avoid erroneous readings due to heat soak.

Where would be a good place to mount the sensor in a Caterham?

As we sprint the car it spends a lot of time idling in the queue for a run and heat soak is a real problem. On previous engines I have located it in the backplate but if there is a more sensible place then I would like to know.

[LesG]

Hi Shaun, I'm guessing you're using a K Series with Jenveys and Scouse airbox like me?

 

I have been mulling over the same issue with my own car, and agree there is quite a lot of heatsoak in the alloy backplate. When I got my car rr'd, the operator commented on the same thing, and suggested I mount the sensor at the rear most section of the airbox, just before the trumpet of no.4 cylinder, in front of pedalbox, IYSWIM? That should get an accurate sample of air, and the area stays relatively cool (I also sprint and know what you mean about under bonnet temps).

 

There was also the suggestion of mounting my o2 sensor outside the bodywork, in the exhaust pipe directly after the collector, thereby getting an accurate gas sample from all cylinders, not just one in the header as now. Although that is perfectly true, and would be better, it's not as aesthetically pleasing!

[Jason Plato]

I have done measurements and the position of the intake air temp sensor is not that important unless you are running in extremes of temp - like less than 5c ambient . I finnaly mounted the sensor on the chassis rail below the air box. the heatsoak issue appears to be unique on the R500 with the ecu map being upset with reading the static heat soak temp with a hot engine and high ambient temps . this high temp clears itself from the airbox after about 1 minute after a few air changes inside the airbox.The emerald map for air temp compensation isn't that dramatic between 10c and 30c and I assume the R500 has more dramatic compensation and hence the engine fluffs and stutters after a time at standstill. my mounting on the chassis rail outside of the airbox still reflects the ambient air temp but doesn't appear to be affecting the ecu after a time at standstill .

 

once moving the air temp sensor almost reflects real intake temps but like I say the compensation in the emerald map isn't much and doesn't appear to make much differnce in normal running in real terms .

[Shaun_E]

LesG - it's a Duratec but otherwise similar issues. I don't run a lambda sensor but for rolling road I have the boss in the collector.

Dave - thanks, that makes sense. I'll mount it there and see how it does.

[Englishmaninwales]

Bringing this thread back to life.. If there is no air temp sensor fitted at all I suppose Emerald has a default, say 10 degrees? Does it really make much difference, except at extremes eg frosty morning and hot summers day? Car is going for mapping soon, will it need to have one for that?

 

Malcolm

 

Edited by - Englishmaninwales on 22 Mar 2014 19:00:46

[Mankee]

Malcolm, I think an Emerald defaults to 20 degrees if no sensor is connected. I never ran one for years on my old engine. Like Dave says, I'm not particularly convinced that it makes much of a difference, especially the use that I put my car through. If you need one, give us a shout and I'll happily lend you mine. The fitting is, usefully, the same as a lambda sensor boss, of which I have a spare also.

[Englishmaninwales]

Mankee

YHM

[SLR No.77]

Malcolm, it's pretty straightforward to make the connection at the Emerald so if you're having it mapped surely it would make sense to fit one now

 

Stu.

[Englishmaninwales]

It's just the car I'm working on doesn't have one at all but have one coming