Barometric pressure sensor question 1993 mustang 5.0

They all use a MAP sensor, the earlier is connected by hose to intake while the later is vented to the atmosphere

Thank you.

I have a custom install that I am trying to sort out. It uses a MAF sensor and a 1993 A3M computer. There is a jumper between the anti fuel relay and the eec power relay. I assume that is to defeat the gas shut-off.

My son and I tracked down the wiring from a mustang wiring diagram. The engine is the forged piston year... i believe earlier than the wiring.

The wiring for the lower portion like engine coolant sensor, throttle position, EGR valve position, barometric pressure, sensors all come from the 1989-90 diagram.

The wiring to the computer for the upper part of the diagram comes from the 1991-93 wiring diagram. fuel pump relay, canister purge, injectors, MAF sensor, etc.

The engine is not running well, and I am trying to figure out what I have and how to diagnose it. I just went through all the wiring to make sure all connections and wire were good. Now I am back to tracking down issues.

My original question you answered was regarding a local mechanic that looked under my hood. He said that there should not be a barometric sensor on the MAF engine. Obviously that gives you an idea of what I am dealing with locally.

I am trying to do the work myself at this point. The motor is in a 1975 bronco. I sometimes go off-roading and worry something may shake loose and I would have no idea what to expect. At this point, I know most of the elements, now I just need to figure what to fix.

The mustang wiring is only wired with four wires to the bronco. Other than that the system is self contained. I just have to figure out some problems.

- low power

- rich fuel

- high idle

- if gas punched or revved at all, it does not idle down very quickly

Those are some of my problems. I am still looking for local mechanical assistance, but I am trying to support local mechanic with this news group. I appreciate any thought my mechanic look more closely at.

The mustang motor is all stock except for a 4° cam advance to lower the torque.... stock cam, forged heads, in-tank mustang fuel pump. I am using the old bronco pulleys, water pump and such. Made the conversion easier.

Well, thanks again for your answer. The mechanic will help I am sure. It's not the type of work mechanics generally seek out. Not much profit involved. He is just going to give me a couple hours and check some things. If I can suggest something from this message board, all the better. I can certainly check many things myself.

Lawson

eec power relay fuel Relay anti fuel relay

Musttanguy wrote:

On Tue, 12 Jul 2005 19:35:29 -0500, Lawson[rem0ve]news rearranged some electrons to form:

any codes?

What codes are you referring to? Sorry, I am learning as I go.

Lp

David M wrote:

On Tue, 12 Jul 2005 21:14:37 -0500, Lawson[rem0ve]news rearranged some electrons to form:

Trouble codes from the computer.

rearranged some

rearranged some

I read the link to the trouble codes and the EEC-IV testing. I don't understand what troubles my mechanic would have been having. I am going to drop by and ask him if he recalls. It sounds pretty straight forward from what I have read in your link. Is it possible that my system would not output codes? As I recall he needed to know some specific information about the car, engine, or computer that was not immediately apparent to him. The people that installed the wiring said that it should plug into any diagnostic with no problem. I do understand more thanks to your post. It looks like I should focus on getting those readings. Is there anything you can think of that would effect whether those readings are available? For something that seems simple, my mechanic seemed confused.

A company that is no longer installed my wiring and computer. They said it would work just like mustang.

My mechanic is a local man who seems to have good experience, but was not having any luck getting codes. I am not sure why.

Laws>On Tue, 12 Jul 2005 21:14:37 -0500, Lawson[rem0ve]news rearranged some

rearranged some

"Lawson[rem0ve]news" wrote in news:SmZAe.103458$gc6.75345@okepread04:

Let's make this perfectly clear:

The Speed Density engines DONT have a MAF and use the term MAP for manifold pressure and they have a tube to a vacuum port.

The MAF configurations use the same part, but called BAP without a tube and it measures atmospheric pressure.