MAP sensor question 2bar or 3bar?

[Jan Larsson]

Found a map sensor in one of my boxes and was wondering if this is the 2bar GN MAP sensor (I think it is), the only numbers on it is "460 6055" just where the letters " C B A" are printed for the electrical connector.

Anyone that can verify this so I know what I have.

 

[mark b]

3 BAR MAP Part number is : 16040748 Application: Turbo Trans Am 1989

 

[Jan Larsson]

No GM part number printed on it unfortunatly, guess it's the delco number, anyone?

 

[72firebird]

I just went and looked at mine on my TTA and it had 749 8313 and C B A right above it. Hope this will help you some.

 

[1BADDAM]

Originally posted by mark b
3 BAR MAP Part number is : 16040748 Application: Turbo Trans Am 1989

Funny,

GMHTP Mag. 1/05

"The three bar-style was never used on a production GM car but reads from 30 psi of boost pressure to 15 inches of mercury."

Goes to show you, ya can't always believe wat ya read.

 

[72firebird]

Originally posted by 1BADDAM
Funny,

GMHTP Mag. 1/05

"The three bar-style was never used on a production GM car but reads from 30 psi of boost pressure to 15 inches of mercury."

Goes to show you, ya can't always believe wat ya read.

Well in a way wouldn't that be true though? Because the TTA wasn't completely "produced" by GM. They were built as regular GTAs then sent to PAS who then built them into TTAs. So then PAS was the one putting the motor in and probably the MAP sensor so it wasn't prduced by GM.

 

[mark b]

Originally posted by 72firebird
Well in a way wouldn't that be true though? Because the TTA wasn't completely "produced" by GM. They were built as regular GTAs then sent to PAS who then built them into TTAs. So then PAS was the one putting the motor in and probably the MAP sensor so it wasn't prduced by GM.

When did GMHTP ever know what they were talking about when it comes to TR's?

 

[87buick3825]

Originally posted by mark b
When did GMHTP ever know what they were talking about when it comes to TR's?

they don't !!

RD

 

[1BADDAM]

Originally posted by 72firebird
Well in a way wouldn't that be true though? Because the TTA wasn't completely "produced" by GM. They were built as regular GTAs then sent to PAS who then built them into TTAs. So then PAS was the one putting the motor in and probably the MAP sensor so it wasn't prduced by GM.

TTA's were produced by GM, they provided the warranty and made the parts. PAS, assembled and did R&D.

This, unlike the 92 Firehawk, similar situation. Did not get a factory warranty.

 

[Jan Larsson]

I think we are a bit off topic ... anyone can tell me if what I have is a GN 2bar sensor?

 

[Razor]

What color is the insert inside where the plug goes on?

If its orange, then it can be either. Any other color and its a 1 bar.

There are no numbers on these sensors. And to make matters worse, the TTA 3 BAR OEM GM sensor is wired backwards from all the other MAP sensors GM makes. So its not one of those things I would suggest plugging into your harness and seeing if the boost guage still worked.

Aside from placing it on a test bench, applying 5 volts to the "A" and "C" terminals.. then looking for 1.6vdc on the "B" terminal. Dont know any other way.

 

[Jan Larsson]

No insert where the plug goes. Guess I'll hook it up to 5V and test it.


The one on my TTA also have the numers 749 8313 like yours 72firebird.

As I mentioned the other one has 460 6055 on it.

I'll measure as per Razor's suggestion and get back on this one, thanks for all the replies

 

[Razor]

On the 2 bar, pin "C" should be 5 volts. On the new 3 bars.. that have a black moulded internal socket. pin "C" is 5 volt. Pin "A" is ground.

On the TTA 3 bar, pin "C" is ground. Pin "A" is 5 volt.

You can buy a 5 volt regulator from Radio Shack in the states for approx $2.00 US.

Part is an LM7805, or AN7805.

12 in, 5 out. Simple.