89' e303...hard intake backfire

Yeah ive heard that its not a good idea to run a auto car with a 5spd ecu and vice versa.

sounds like a lean pop. How are you monitoring AFR?

Mine does the same thing, Smells like gas bad at idle but has the lean backfire through the intake when you rev it.

On an otherwise stock car, what is the solution to getting it more fuel.

The previous owner installed the e-cam in mine without any other supporting mods. The FPR and Filter are new (stock) plugs, wires, cap etc. So if its running lean I have to ask, Why would it run lean and whats the solution? While most of you out there have more experience with EFI than I do, just throwing an adjustable FPR and giving it more fuel seems like an extreme step to take.

My car is an 88 and still has SD computer. No code other tham 94 and 44 for lack of smog pump.

lincoln+ford said:

Yeah ive heard that its not a good idea to run a auto car with a 5spd ecu and vice versa.

Click to expand...

this is totally incorrect. many members on this site as well as the corral have done this including me.
my car was an aod now it has a 5sp and i'm running the same comp.

Jeffs88 said:

Mine does the same thing, Smells like gas bad at idle but has the lean backfire through the intake when you rev it.

On an otherwise stock car, what is the solution to getting it more fuel.

The previous owner installed the e-cam in mine without any other supporting mods. The FPR and Filter are new (stock) plugs, wires, cap etc. So if its running lean I have to ask, Why would it run lean and whats the solution? While most of you out there have more experience with EFI than I do, just throwing an adjustable FPR and giving it more fuel seems like an extreme step to take.

My car is an 88 and still has SD computer. No code other tham 94 and 44 for lack of smog pump.

Click to expand...

Changing the heads, or the cam can significantly change the amount of air that the engine is breathing, after all that's the point. However, the speed density EEC has no way to recognize that change. So based on the reading from its O2 sensors it can only modify the fuel by 12.5% (more or less fuel) from the speed density base tables. MAF cars will modify based on the amount of air that is being moved and recognizes the change in volumetric efficiency associated with aftermarket installations.

Adding an AFPR will give you the ability to get rid of the lean condition, but it will also cause you to enrichen the fuel curve everywhere. The problem is that most power adding modifications don't add an even amount of air flow across the RPM band. So, adding fuel pressure will fix your lean condition, but may make other places in the powerband overly rich. That's obviously a better place to be, but you can do better still.

There are only 2 practical solutions that I can see if you want to run EFI and make significant modifications. Either install an MAF with an appropriate computer, or get a piggyback chip to tune your SD setup. Having the ability to tune it yourself gives you the most flexibility but requires the most work. Installing an MAF can make future modifications less work intensive while keeping you pretty well in tune, but they also add complexity to the system. I like tuning my SD setup, and I don't like troubleshooting MAF problems when they happen. That said, an MAF car tuned correctly will run just as hard as a SD car tuned right, too. To each their own.

Chris

BYRDPE said:

this is totally incorrect. many members on this site as well as the corral have done this including me.
my car was an aod now it has a 5sp and i'm running the same comp.

Click to expand...

Oh... so that explains the dissappointing results...

pressure should not drop below 33 (vac installed) regardless if the engine is running or not. Sounds like the fuel pump isn't pumping out anymore than a 90 year old man.

yeah i am running a auto computer in my 5 speed car, runs great

BYRDPE said:

this is totally incorrect. many members on this site as well as the corral have done this including me.
my car was an aod now it has a 5sp and i'm running the same comp.

Click to expand...

Your missing the point that lincoln+Ford was trying to make.

You can run A9P in either setup, and not have to worry about frying the ECM.

If you run a A9L ECM in a car that came equipped from the Factory with a AOD. You can fry the ECM.

It has nothing to do with the ECM itself. It has to do with the harness and its wire routing for the NSS and NDS.

As long as these issues are took care of, you can run either ECM.

lincoln+Ford wasnt speaking from a Performance stand point. Just a compatability issue is all.

As long as you keep voltage from reaching the SIGRTN circuit when using a A9L in an AUTO setup, your golden.

Not trying to hijack the thread. Just want to make sure im understanding this correctly. I have a car that was a 4 cylinder auto and converted it to a 5.0 5 speed with an automatic O2 harness not sure about the engine harness if it was an auto or 5speed. What do I need to check on the O2 harness? and how do i tell if i messed something up in the computer by frying the NSS or NGS? what does those even mean? It runs ok but it wants to die when its cold and hessitates at times.

Thanks,
Colby

Dumping The computer diagnostic codes on 86-95 Mustangs

Revised 19-May-2009 to update drawing for dumping the codes on 86-88 Mustangs with no check engine light.

Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

See Troublcodes.net Trouble Codes OBD & OBD2 Trouble Codes and Technical info & Tool Store. By BAT Auto Technical





If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see Digital Ford Code Reader (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.