Random questions about my car, fixing & upgrading things...(o2 sensor, map, fuel cut)

[Mysterio]

First of all. My car is an 87 charger shelby.

My o2 sensor isn't hooked up, he has the harness the o2 sensor plugs into cut between the cars wiring harness and the o2 sensor.

So my question is, which 3 wires are for the stock o2 sensor? I see 3 wires comming from the wiring harness on the passenger strut mount, IIRC they were red with blue, and then 2 black wires? The black wires MAY have had stripes on them I couldn't see it was dark. Those 3 wires were soldered together which I assume he did to loop the wiring for the o2 sensor and not have to reconnect it.

Are these the correct wires for the stock o2 sensor? If so which wires are which? Anyone got a picture of their 3 wire to 4 wire conversion so I can see the coloring & locations of the wiring.

Secondly, my car has a charger air temp sensor that is not installed. It's got the blow through intake on it, with no port for it. I bought a vacuum block recently that I'm going to install off the back of the intake manifold vacuum port. There is another vacuum port on the front that goes to the MAP and stuff. Is that port the same thread size as the charger air temp sensor? Can I put the vacuum block on the back of the intake manifold and run everything off that spot, and then thread the charge air temp sensor into the front of the manifold? Is that sensor even required??

Lastly, this is my first dodge, turbo, or even 4 banger for that matter. I've been around v8's forever. Where is the MAP? What does it look like? Everyone talks about 3/2 bar and such but I don't even know where the MAP is or what it looks like.


Related to the O2 sensor, right now if I run anything more than 10 psi of boost my car will fuel cut pretty badly, will having the o2 sensor disconnected cause this problem? Or is there something else anyone can think of that I should look for? I'm told the stock fuel cut isn't until 14.7 psi so I should be able to run more than 10.


I'm really trying to restore this guy and make it run great and look nice. So anyones help is GREATLY appreciated.

[Anonymous_User]

Hmmm....

OK, you've got an '87 running without an O2 hooked up. Are you getting a check engine light? If not, is it possible you have an aftermarket calibrated computer that isn't using closed loop, similar to the S60 cals? But, those were SMEC ('88 style wiring).

Charge air sensor should be the same size tapped hole as the vacuum port.

[cordes]

OK, first off, the car should have a 1 wire O2 sensor for that year if I am not mistaken. Since it is blow through that means that someone has converted the car to TII. Now, since you have a charger, this is a bit more complicated due to the fact that many people simply upgrade to 86/87 GLHS electronics, which only requires running 2 added wires. However, once could have also upgraded to 87 TII electronics, which would have come on all TII cars except the GLHS.

As far as the manifold goes, all the holes should be 3/8ths NPT, and you can put things about anywhere you want. What ever works for you.

Also, if the map is on the LM which is under the dash on the pass side behind the kick pannel. It would be the littl black square on it with the vac line going to it. I would believe that you have GLHS electronics in the car if the map is on the LM.

[Mysterio]

Hmmm....

OK, you've got an '87 running without an O2 hooked up. Are you getting a check engine light? If not, is it possible you have an aftermarket calibrated computer that isn't using closed loop, similar to the S60 cals? But, those were SMEC ('88 style wiring).

Charge air sensor should be the same size tapped hole as the vacuum port.

As far as I know it's the stock computer. Guy I bought it from never said anything about it.

There is no check engine light going on though. Not really sure how that's going on. Unless I am getting codes but the CEL isn't coming on?

OK, first off, the car should have a 1 wire O2 sensor for that year if I am not mistaken. Since it is blow through that means that someone has converted the car to TII. Now, since you have a charger, this is a bit more complicated due to the fact that many people simply upgrade to 86/87 GLHS electronics, which only requires running 2 added wires. However, once could have also upgraded to 87 TII electronics, which would have come on all TII cars except the GLHS.

As far as the manifold goes, all the holes should be 3/8ths NPT, and you can put things about anywhere you want. What ever works for you.

Also, if the map is on the LM which is under the dash on the pass side behind the kick pannel. It would be the littl black square on it with the vac line going to it. I would believe that you have GLHS electronics in the car if the map is on the LM.

When I was looking at his 4 wire he has in there. There was only 1 wire connected to it, a large black wire coming from the wire harness above the fuel injectors over the intake manifold. Is that the correct wire from the single wire o2 sensor that came factory?? I assumed the guy just didn't know what he was doing and had that hooked up to some random wire.

If that is the correct wire, then I'll just need 2 grounds and a ignition source for the heater, that's easy enough.


I was really confused myself as to why the car would be running fine without the O2 sensor hooked up. I mean, it runs fine most of the time. Like I said anything above 10 psi of boost and it fuel cuts, and sometimes if I push it hard the car will keep stalling itself, but if I push it hard again, or simply rev it to like 6 grand real fast, it will go back to idling fine.

[BadAssPerformance]

There is no check engine light going on though. Not really sure how that's going on. Unless I am getting codes but the CEL isn't coming on?

Turn the key on-off-on 3 times and leave it on (not run, but on) and leave it on the third time and the CEL should flash out any coded, if there is no codes it will still flash 55, if not flashed, the light might be burnt out or disabled.

When I was looking at his 4 wire he has in there....If that is the correct wire, then I'll just need 2 grounds and a ignition source for the heater, that's easy enough.

got pics?

And did you confirm which Logic Module is in it? There are several possibilities for '87.

[Mysterio]

Turn the key on-off-on 3 times and leave it on (not run, but on) and leave it on the third time and the CEL should flash out any coded, if there is no codes it will still flash 55, if not flashed, the light might be burnt out or disabled.



got pics?

And did you confirm which Logic Module is in it? There are several possibilities for '87.

I'm going to go out and check which LM is in my car today before I run to the store.

I'm going to go check if ive got any codes and then i'll take a picture of the mystery wire running into the o2 sensor.

[Mysterio]

Ok I FINALLY went out (3 am LOL) to check which LM I have in my car.

The MAP sensor is connected to the LM, it is not seperate.

The numbers on the MAP sensor:

5227324
34616
8614C

And on the side of the LM here's the product number & Date:

5227533
4/23/86


I pulled codes and all I got was a 21 which is an o2 sensor code, and seeing as it's not hooked up that makes sense.


Now that you know that about the LM, what does that tell you about the wiring? I really have NO idea what wiring is in the car or which wire(s) I should be looking for to connect my o2 sensor to it. Since he snipped the wiring harness for the o2 sensor between the engine & the harness I don't know where those wires goto. And can't find any matching colors so I don't think that's the origional harness for it? I don't know.

Any help would be appreciated. Maybe a picture of o2 sensors that are hooked up so I can see what colors your wires are and that will give me something to look for in my wiring.

Like I said I found 2 black wires & a red/blue wire that are soldered together right by the o2 sensor, they look like they may have been for a 3 wire o2 sensor? I don't know.

[cordes]

If it has the map on the LM, and has been converted to TII, it is almost certainly GLHS electronics. I have searched on D-cal and can't remember where the part #s for the LM is, so I am not 100% sure.