I was under my (new to me) mustang yesterday and found that the pass side 02 sensor was broke off at the bung and the rest of the harness missing. The main harness connector was dirty so I know its been missing for a while now.
The plugs look nice and tan and it runs well. (factory stock engine w/5 spd)

I've only driven the car about 50 miles since buying it and will be putting new 02s in soon.

1- Shouldn't this throw a CEL? I don't have one showing.

Also, I have no cats. Again no CEL
2 - What is required to run no cats on a 89GT? (computer wise)

I've experience tuning OBD 2 fords w/SCT pro-racer software. But I've never gotten into something this old (1989) This winter I'll be looking to install a larger MAF, 24 or 30lb injectors, cobra intake, & 4.10s. Heads, cam, & exhaust will come in another yr or two.

3 - What software / hardware is needed to tune these things?
3a - Is this even needed for a "bolt on" 5.0L?

Regards,
Rich

 

1. It might not give a CEL, but it should throw a code if you run a KOER test.

2. Nothing. Your cars computer doesnt know that there are cats (or a lack of) in the exhaust. It doesn't care either.

Additionally, 24 or 30# injectors in your car would be completely pointless without h/c/i mods.

3. Moates Quarterhorse, Tweecer, PMS, stand alone. I recommend them in that order.
3a. This is a very touchy subject. Mods will always benefit from a tune. however the fox ECM's seems to have a bit more... flexability. They have a very crude form of EFI, and can cover a wide array of changes. This is because it is a less exact system. The newer cars have more sophisticated systems that are less forgiving, but can be tuned with finer precision.

 

Thanks for the input.

If I get into the intake this winter I'll swap the injectors for two reasons. One, clean and flow matched injectors are a good thing. Two, I still have all my nitrous equipment. And, I favor dry shots on a engine with large length intake runners. Single point wet nozzles just can't get the cyl-to-cyl distribution as good as using the injectors.

Regards,
Rich

 

With these tuning softwares, can I get to and adjust the Mass air flow tranfer curve / chart?

Regards,
Rich

 

yes you should, the quarterhorse from what I've read is decent

 

If you decide to go with the quarterhorse, you MUST get a wideband. Trying to tune without it can cause severe engine damage.

Once you are all setup, you can datalog what your car is doing. You can then take those datalogs, and send them to someone like myself, who will inspect your logs, review your tune, and make changes to the tune. You will then recieve the new tune back with instructions on what you should do next... like what types of driving would like to be seen in the next logs.

 

I know all about tuning OBD2 fords. I'm well equipped for doing this. I just was not sure about how best to get to my 89s tune and what soft/hard combo to use. Thanks for the list of resources!

Once I get there I'd certainly like a reality check that my tune is right. As I'm sure you know there are many different limiters that are often hidden. As well as mapping the MAF being the number one thing to do.

Thanks,
Rich