What's hotter?
What's hotter?
Author
Discussion

Chilliman

Original Poster:

12,422 posts

191 months

Saturday 29th June 2013
quotequote all
So, my temporary air temp sensor is tie wrapped to the outside of the plenum opposite side to the throttle bodies. I can't use the air temp sensor (the one I should be using) that's 'in' the plenum because the connector is corroded and it was telling the ECU (MS2) that the air temp was minus 30, resulting in massive over fuelling. So, whilst on the move, the temporary air temp sensor is sending the ECU the engine bay temperature not the air temperature in the plenum. So what's hotter? I'm thinking the air going into the plenum is likely to be a lower temp than the engine bay. It would be reasonable to assume that if the ECU is being told the air temp is hotter than it actually is then I'm probably running too lean... Will be reinstating the plenum sensor soon.... So wotcha think guys, is underbonnet higher or lower than plenum temperature?

It's a density thing which, being dense I find interesting smile

Chilli smile

Sardonicus

19,454 posts

251 months

Saturday 29th June 2013
quotequote all
Outside the plenum is hotter, if you need to run temporary like this then insulate it a tad to stop it soaking up to much eng bay heat, it will probably heat-soak like a bd when you switch it off hot when its naked like you currently have it.

Chilliman

Original Poster:

12,422 posts

191 months

Saturday 29th June 2013
quotequote all
Thought so smile Thanks Simon, It might explain why I got such low figures on the last RR whistle

Edited by Chilliman on Saturday 29th June 10:49

Harrytsg

1,264 posts

192 months

Saturday 29th June 2013
quotequote all
Its quite surprising how the heat differs, I used one of these when setting up my fan controller.

http://item.mobileweb.ebay.co.uk/viewitem?itemId=1...

Handy thing to have around, though not necessarily pointing at children's faces.


SILICONEKID343HP

14,997 posts

261 months

Saturday 29th June 2013
quotequote all
I thought hotter the air weaker the mixture and if the sensor fails it goes to default setting which is not rich .

Hoofa

3,153 posts

238 months

Saturday 29th June 2013
quotequote all
Think the answer to this is stop posting and get your air sensor fitted in the right place !! Otherwise you risk the fuelling to be all over the place. The end smile

Chilliman

Original Poster:

12,422 posts

191 months

Saturday 29th June 2013
quotequote all
Concise and incisive as always Nigel smile

Hoofa

3,153 posts

238 months

Saturday 29th June 2013
quotequote all
To be honest in the pipe heading into the plenum is ok, i put a bit of heat shielding around the sensor to stop a bit of heatsoak on standing traffic.

db484bhpv8

8,676 posts

250 months

Saturday 29th June 2013
quotequote all
I copied Simons idea and relocated mine to a boss welded into the pipe directly after the air filter. Been much better behaved since.

Sardonicus

19,454 posts

251 months

Saturday 29th June 2013
quotequote all
db484bhpv8 said:
I copied Simons idea and relocated mine to a boss welded into the pipe directly after the air filter. Been much better behaved since.
Good man, you know it makes sense, hope my Brother dont read this has he will want his moved too. whistle

SILICONEKID343HP

14,997 posts

261 months

Saturday 29th June 2013
quotequote all
Sardonicus said:
ood man, you know it makes sense, hope my Brother dont read this has he will want his moved too. whistle
Is it ok just to extend the cable and join it twice or will it change the values ..Where can I get a boss to fit the sensor. Thinking of moving it .

If it does suffer from heat soak does it weaken the mixture.

Edited by SILICONEKID343HP on Saturday 29th June 18:56

phazed

22,508 posts

234 months

Saturday 29th June 2013
quotequote all
I was told by Shaun that you can lengthen at will.

Sardonicus

19,454 posts

251 months

Saturday 29th June 2013
quotequote all
phazed said:
I was told by Shaun that you can lengthen at will.
You can its a 5 volt signal and won't mind extending wink

SILICONEKID343HP

14,997 posts

261 months

Sunday 30th June 2013
quotequote all
Your right about heat soak ! my car did not like the heat today ,idle ran weaker ,going to move the sensor.

Could I get away with not using a boss and just drill a hole and gluing it in .

Sardonicus

19,454 posts

251 months

Sunday 30th June 2013
quotequote all
SILICONEKID343HP said:
Your right about heat soak ! my car did not like the heat today ,idle ran weaker ,going to move the sensor.

Could I get away with not using a boss and just drill a hole and gluing it in .
No problem, go easy if you use silicone though whistle

SILICONEKID343HP

14,997 posts

261 months

Sunday 30th June 2013
quotequote all
Sardonicus said:
o problem, go easy if you use silicone though whistle
Where on the megasquirt can I see it`s actually working .. Is it air temp on the gauge cluster . how much does the air temp actually adjust the afr ?

Hoofa

3,153 posts

238 months

Sunday 30th June 2013
quotequote all
Daz step away from the mega squirt !!! Just drive the damn thing

SILICONEKID343HP

14,997 posts

261 months

Sunday 30th June 2013
quotequote all
Hoofa said:
Daz step away from the mega squirt !!! Just drive the damn thing
Could not put my hand on the sensor ,so bloody hot . idle was erratic and leaner.

Sardonicus

19,454 posts

251 months

Sunday 30th June 2013
quotequote all
SILICONEKID343HP said:
Where on the megasquirt can I see it`s actually working .. Is it air temp on the gauge cluster . how much does the air temp actually adjust the afr ?
Enough wink the scaling can be altered but leave it alone.

SILICONEKID343HP

14,997 posts

261 months

Sunday 30th June 2013
quotequote all
Sardonicus said:
nough wink the scaling can be altered but leave it alone.
Are you advising me not to move it ?