anyone here know Vauxhall 1.7 diesels?

[turbopete]

ok, so probably the wrong place to ask BUT at work we have an 04 plate Vauxhall Combo 1.7Di crew van. EML light is on so I read the codes using a little hand held sealey code reader which came up with a code (I forget the number I'm afraid but its a generic to ALL vehicles code) which is explained onscreen as a fault in the 'manifold absolute pressure circuit'

van has over 226k miles on it and is going for MOT Monday as we want to know how much spending it will need to decide whether its worth the money or just replace so my thoughts were, do these have problems with the MAP sensor or its related circuit, that's common and easy to find/cure? or is it likely to have an air flow meter issue (I cant get any live data as our Delphi clone refuses to connect to this van) and if it is an actual MAP sensor, does anyone know where exactly its located? any other ideas/suggestions gratefully received. thanks

 

[M80]

I really would like to offer help Pete, as you have for me many times, but sorry it's beyond my knowledge. But good luck.

 

[Craiglxviii]

This was the one thing my SIL never had problems with on her mobile horse tack shed/ Astra estate... sorry I cannot help out chap.

 

[00slk]

If it is anything similar to my Jaguar 2.2 diesel the sensor should be located somewhere along the air intake, they can range in size and will be connected with a plug for the electrics.
Apart from that sorry can't help, all my Vauxhalls were petrol........And old!!!!

 

[LostKiwi]

A quick Google image search suggests it's back left of the engine? Only £35 so worth trying.

 

[Wighty]

Is it worth buying some MAF spray cleaner to clean the air flow sensor . (Apologies if MAP is a different thing )

 

[LostKiwi]

Yeah MAP is different. MAF measures air flow, MAP measures manifold absolute pressure.
Some cars have MAP, some MAF, some both. For example Smarts have MAP only, Saab use MAP and MAF.

The purpose of MAP and MAF is the same - to calculate the amount of fuel required for the air present going into the cylinder.

 

[turbopete]

Thanks guys. we are just going to send it for MOT Monday and see what the tester says. at this mileage it may need considerable other work making it uneconomic to repair so we will wait and see.

after that I may be on the lookout for another job.........(not getting made redundant, I hope, but I need something with a decent pay grade and more than 16 hours paid per week)

 

[umblecumbuz]

The purpose of MAP and MAF is the same - to calculate the amount of fuel required for the air present going into the cylinder.

... Although, as I understand it, the way the two sensors go about their tasks is somewhat different.

The MAF measures flow - as its name indicates.
The MAP measures pressure.
The two things are obviously not the same of course.
Both send signals to the ECU, and the ECU responds by metering the fuel flow rate for optimum efficiency.
Does that sound right?

 

[LostKiwi]

... Although, as I understand it, the way the two sensors go about their tasks is somewhat different.

The MAF measures flow - as its name indicates.
The MAP measures pressure.
The two things are obviously not the same of course.
Both send signals to the ECU, and the ECU responds by metering the fuel flow rate for optimum efficiency.
Does that sound right?

Correct.
Both also use inputs from the throttle position sensor and inlet air temperature sensor to calculate air density in order to correctly calculate fuel trim.

 

[Westheath]

Thats the Isuzu engine.

Its under the thotttle body on the right side,
follow large plastic hose top right, look under it near the TB,
it's on the manifold.

The later 1.7 ecotec is easy to see.
Pull engine cover off and it's in front of you on the manifold top left, one retaining bolt.

Also on the z17 dtr & dtj engines it is located over the rear,
on the manifold far left, this pic is from the rear.