Obd 2 302/351 How To

enyawix said:

Emissions testing.

Click to expand...

Huh? What does converting to OBD2 have to do with emissions testing?

enyawix said:

Some places connect to the OBD2 port on all vehicles 1996 and newer as part of the emissions testing, and exempt cars 1995 and older from testing.

Click to expand...

Correct. I know that my '88 is exempt from the sniffer test completly, so emissions are no longer a concern to me and my daily drivers get the plug in test and pass if no CEL...

But this statement

Tightening emissions standards and rising fuel prices have made this a priority for me.

Click to expand...

Leads me to beleive your car is perhaps not exempt from a sniffer test? Without knowing your state, it's hard to judge where you are coming from.


I'm just confused to which I ask if an explorer EDIS does have an impact on actual tailpipe output, or if you are merely looking for a loophole to get out of emissions testing by converting to OBD2 and merely having to do a plug in test?

If ths first is true, then my technical question remains for which I have an actual curiousity. How does an EDIS system effect actual output emissions on the 5.0? I realize Ford had to swap to OBD2 at some point on the explorer, but the tailpipe standards on a truck are looser than passenger car. So would the EDIS system have enough of an impact to lower a cars output to the point where it passes more stringent standards?

If the 2nd point is true, I would want something in writing from a gov't agency that states an OBD2 retrofit on an older car allows it to be tested as if it was factory equipped with that management system.

Mustang5L5 said:

If ths first is true, then my technical question remains. How does an EDIS system effect actual output emissions on the 5.0? I realize Ford had to swap to OBD2 at some point on the explorer, but the tailpipe standards on a truck are looser than passenger car. So would the EDIS system have enough of an impact to lower a cars output to the point where it passes more stringent standards?

If the 2nd point is true, I would want something in writing from a gov't agency that states an OBD2 retrofit on an older car allows it to be tested as if it was factory equipped with that management system.

Click to expand...

This is really the thing right here. I've had to pass emissions testing in a LOT of different places. Some are better/easier than others.

I can say this about the places that I've been that actually look for error codes:

If you have say, a 1989 Mustang that came OEM with an A9L and they are required to check for codes, it will fail emissions based solely on the fact that you do not have the test port that came equipped on your car. In many cases, one would not even pass the visual inspection. End of story.

If the OP thinks that the emissions control people are going to sit back with a cigarette and chatter about the marvelous job that was done to put an OBD2 computer into and OBD1 car, then he is sadly mistaken. Most of these clowns are not even car people. They look at a screen or a book. Their procedure tells them to take emissions accessory 21b and insert into slot 16f. If 21b doesn't fit 16f or if 16f is relocated or doesn't exist... FAIL. They don't take the time to discover the why or how... It's not their problem. What is supposed to be on the car is NOT and that's enough for them to fail you and move on to the next one before the lunch break begins.

If you have the same car in a state/county that DOESN'T check for error codes but has a dyno, idle, or high idle sniffer test then the only thing that matters is what is coming out of the tail pipe. OBD2 vs. OBD1 makes ZERO difference in this case. The same adjustments to emissions control methods can be made with EITHER of these setups using the same methods but different equipment. EITHER of these ECUs can be tuned so it makes no sense to me why anyone would retro fit.

If things like what the OP is talking about in this thread were true, then we'd all be ditching the factory catalytic converters and smog pumps in favor of 3-way catalytic converters. They're more efficient and reduce emissions more than the factory pieces. Why don't we? Because that's not how they operate. They want the factory equipment or the car fails, REGARDLESS of the fact that the OEM converters are inferior.


The best way to pass emissions is and always has been, to have on the car what CAME on the car and to ensure that it is all in good working order.

Bullitt347 said:

If you were to install a 5.0 coyote engine into a Fox Body car, then the car would be tested to the standards of the year of the 5.0 coyote engine.

Click to expand...

This is the first time I've ever seen/heard anything resembling this. In the places that I've been (one of those being CA), if you roll up in a 1989 Mustang (confirmed by VIN) then you have to pass emissions standards stated for that year, make, and model. They don't care about your mods, they don't care about any of that and will not spend time trying to figure it all out. They will perform the standardized test for a 1989 Mustang. If for whatever reason they cannot perform those tests as stated in their manual, then you fail. If the vehicle doesn't meet the minimum requirements for that vehicle then you fail. It's the problem of the owner of the vehicle to ensure that it can pass emissions testing as it is stated in their manual.

Noobz347 said:

This is the first time I've ever seen/heard anything resembling this. In the places that I've been (one of those being CA), if you roll up in a 1989 Mustang (confirmed by VIN) then you have to pass emissions standards stated for that year, make, and model. They don't care about your mods, they don't care about any of that and will not spend time trying to figure it all out. They will perform the standardized test for a 1989 Mustang. If for whatever reason they cannot perform those tests as stated in their manual, then you fail. If the vehicle doesn't meet the minimum requirements for that vehicle then you fail. It's the problem of the owner of the vehicle to ensure that it can pass emissions testing as it is stated in their manual.

Click to expand...

That's how it would be in MA as well

I think the one stipulation is the engine must be newer than the car. So you could swap a newer engine into an '88, but doing a 302 swap to a 2001 Mustang would be a no-no.

Mustang5L5 said:

That's how it would be in MA as well

I think the one stipulation is the engine must be newer than the car. So you could swap a newer engine into an '88, but doing a 302 swap to a 2001 Mustang would be a no-no.

Click to expand...

I 'think' that this can also be done but if you swap a 302W into a 2001 then it has to pass emissions standards for the 2001. If the county you're in does check fault codes for OB2 and you don't have the ability to be tested for those codes then you fail.

Bullitt347 said:

The car has to meet the emissions standards of the newer engine that is installed in the car. If you managed to get a Coyote powered Fox Body thru emissions without a visual inspection, you could probably get by, but any visual inspection would get you flagged and the car must meet the standards of the newer engine. When I got emissions repair certified by Washington State they were very firm about this point.

Click to expand...

That is a first for me. I've not been anywhere where that was the case or for that matter, any place that would even take the time to decipher the model year for motor.