MAP Sensor - how do you test?

duaned · 05-09-2006, 10:29 PM

Done some searching but came up without the info I'm looking for.

Question:- I know what the MAP sensor is and it's primary function, but is their a way of testing this component on an AU to ensure that it is working to spec. without visiting an authorised dealer?

And another:- Where is it located on the AU (pics?) and is it easy to replace?

Sorry for the questions, but it seems many AU owners have had these sensors fail from 70,000kms upwards reducing performance whilst being un-aware until service time.

Thanks, Duane.

ratter · 05-09-2006, 10:39 PM

If it was not working, you should expect a trouble light to come on, but if is reading incorrectly, it may not show as a trouble code.

You will need a scan tool to check the computers live data and make sure it is operating as the motor is revved.
or If you can find what the electrical output should be, you could test it with a vacuum pump.

**Stav** · 05-09-2006, 11:22 PM

Looking from the exhaust side at the throttle body..below where the throttle body is mounted in the manifold is where it is mounted.Its a not so easy spot to reach.

jonbays · 06-09-2006, 05:50 PM

Test it first and see if it really is stuffed. Are there any symptoms you have?

it is a bugger to get at under the throttle body under the fuel rail and its a combined inlet air temp and manifold absolute pressure sensor.

You can tap into the wiring and test the DC voltage and see if its sort of in range but its a frequency not voltage sensor stricctly. I can post up some info on basic testing for you tonight.

duaned · 06-09-2006, 08:00 PM

Thanks for the replies guys. There is so many components that talk to the ECU, and my research shows the MAP sensor seems to be the most unreliable.
And as it can cause a loss of performance, I want to ensure i am getting the most from the AU in regards to the performance. Haven't G-TEK measured it yet (AIR is still closed I believe) but I am hoping for a high 14 sec pass, un-opened. Time will tell....

jonbays · 06-09-2006, 08:09 PM

[QUOTE=ddarby]Thanks for the replies guys. There is so many components that talk to the ECU, and my research shows the MAP sensor seems to be the most unreliable.
And as it can cause a loss of performance, I want to ensure i am getting the most from the AU in regards to the performance. Haven't G-TEK measured it yet (AIR is still closed I believe) but I am hoping for a high 14 sec pass, un-opened. Time will tell....[/QUOTE

The MAP sensor is very robust and the ecu has built in fail safes and trims so unless there is an error code or a problem this isn't going to do anything to help you get a 14.

Casper had a dud MAP its true but that's only ONE I know of. there are a lot of AU falcons out there!

janek · 06-09-2006, 08:53 PM

Through personal experience, the tests any normal person can run will show nothing. The scantool/error code reader wont show it up either.

They only cost $108, its well worth a try... i cut just over a second off my 1/4 time, and at least 20% better fuel consumption

jonbays · 06-09-2006, 09:00 PM

$108 wouldnt be from FORD would it? seems too cheap

jonbays · 06-09-2006, 09:01 PM

I agree about the testing they are hard to test with basic test equipment.

ratter · 06-09-2006, 10:47 PM

A scan tool which shows live data, should show what signal is coming from the sensor, but you will need to know what is correct info and what is wrong.

Casper · 07-09-2006, 11:24 AM

Mine is the only one I know was proven to be faulty. It also DID throw an error code up on the scan tool when tested (although we overlooked it due to what we expected was a dud O2 sensor being the suspected problem).
The symtoms are hard to miss though. MASSIVE fuel usage (and I mean 280kms from a tank in normal driving), huge A/F ratio (dropping into the 9/1 ratios) and a lot of unburnt fuel coming out the back under heavy acceloration. All of which lead us to to the MAP sensor in the end (I'll give Brenden at JMM a big kudo for this as he spent a lot of time finding it and was the only one who worked it out.. he did exceptionally well on this).

janek · 07-09-2006, 01:41 PM

Quote:

Originally Posted by Casper

Mine is the only one I know was proven to be faulty. It also DID throw an error code up on the scan tool when tested (although we overlooked it due to what we expected was a dud O2 sensor being the suspected problem).
The symtoms are hard to miss though. MASSIVE fuel usage (and I mean 280kms from a tank in normal driving), huge A/F ratio (dropping into the 9/1 ratios) and a lot of unburnt fuel coming out the back under heavy acceloration. All of which lead us to to the MAP sensor in the end (I'll give Brenden at JMM a big kudo for this as he spent a lot of time finding it and was the only one who worked it out.. he did exceptionally well on this).

Make that 2 shane... Mine did prove to be bad as well.

Yup, $108 was from ford... Thats for the au2/3 one... not the wall mounted one, the one in the manifold...

If you ever try towing in the city with a dead map sensor, expect 200km normal towing, and 300 MAX unloaded city driving. Its an ugly thought that my car was using more than a 351c at some point.

Using scantool would be ideal, but not everyone is willing to fork out the $$$...

T2TL50 · 07-09-2006, 07:10 PM

man!! my car sounds like it has all those issues!! unburnt fuel 320 per tank.. Where can i have this tested and how much??

Casper · 07-09-2006, 07:15 PM

Quote:

Originally Posted by T2TL50

man!! my car sounds like it has all those issues!! unburnt fuel 320 per tank.. Where can i have this tested and how much??

You dont have a MAP sensor Rick.. you have a V8.... MAF sensor for you, works totally different

Futura01 · 07-09-2006, 07:31 PM

Well ebay has the fault scanners for ford $40.00 and there handheld

ratter · 07-09-2006, 07:33 PM

Quote:

Originally Posted by Futura01

Well ebay has the fault scanners for ford $40.00 and there handheld

I'd be surprissed if they actually can read live data, probably just check for codes only

Futura01 · 07-09-2006, 07:37 PM

yeah i am not sure on how well they work either ???

chrispie123 · 07-09-2006, 08:02 PM

are map sensors the same for an ef and au while they be a swap over change as i have tose symptons replaced o2 sensor leads plugs and coil pack and still only 280 per tank