94-95 Computers...what's wrong with them?

[greenlantern]

Whats wrong with the 94-95 computers?

The short answer is they suck. The 89-93 stangs had a much more aggressive air fuel curve. That combined with speed shifting caused Ford to have to replace a crap load of Trannys that were still under warranty. To protect themselves from this they produced a much less aggressive program for 94-95. The new program pulls timming while accelerating and while shifting.

The fix? I think final 5-0 pretty much summed it up. Any computer in the right hands will undoubtedly deliver what you want. I myself went the route of the A9L PIH kit. To this day I am very happy with it. This sort of fix by today's standards is considered to be an old school one but works very well. Many of the guys that run this set up look at it as a put it in and forget about it fix. Eventually I ended up getting a tune which means I spent more money getting an sct chip.

If I had it to do all over again I too probably would have gone the direction of the Tweecer. The problem here is learning how to use the damn thing, you still might find yourself paying someone else to help you get it tunned right.

Good luck

 

[SQUEEZE&STROKE]

If I had it to do all over again I too probably would have gone the direction of the Tweecer. The problem here is learning how to use the damn thing, you still might find yourself paying someone else to help you get it tunned right.
Good luck

Amen to that!
I had the PMS and It was pretty daunting to start...luckily I had some friends that have used them and helped me for free...otherwise I would have ended up paying!!!

 

[final5-0]

I bought my tweecer a year or so ago and I'm still figuring it out. I got the basics down, but from there it's all a matter of trial and error.

I'd have to agree with you John. Once you get a basic understanding about what that little silver box is doing you really start to understand why your car is not behaving like it used to.

btw ...... I've always suspected that bad behavior has something to do with all of those hot rod parts we put on our cars.

Just be careful with it, and make small adjustments at a time.

Preach on Brother John

Don't do what I do and test the waters by changing values from one extreme to the other to correlate it's function.

Hmmmmm ...... me thinks that this looks like the voice of experience speaking quite loudly

I read up on our computer and the tune for a few months before I bought the thing which helped a lot.

I hear ya ...... gotta do that doo diligence

Later
Grady

 

[final5-0]

Whats wrong with the 94-95 computers?

The short answer is they suck. The 89-93 stangs had a much more aggressive air fuel curve. That combined with speed shifting caused Ford to have to replace a crap load of Trannys that were still under warranty. To protect themselves from this they produced a much less aggressive program for 94-95. The new program pulls timming while accelerating and while shifting.

The fix? I think final 5-0 pretty much summed it up. Any computer in the right hands will undoubtedly deliver what you want. I myself went the route of the A9L PIH kit. To this day I am very happy with it. This sort of fix by today's standards is considered to be an old school one but works very well. Many of the guys that run this set up look at it as a put it in and forget about it fix. Eventually I ended up getting a tune which means I spent more money getting an sct chip.

If I had it to do all over again I too probably would have gone the direction of the Tweecer. The problem here is learning how to use the damn thing, you still might find yourself paying someone else to help you get it tunned right.

Good luck

I see all of your points that you make and understand where you are coming from.

Lets face it ...... the Tweecer is not for everybody.

For those who are looking for an easier way, the PMS seems to satisfy most of them from the posts I've seen on the various sites.

As for learning how to use the thing.......................

To get started in self tuning is no different than getting started in our hobby of modding Stangs.

If one will come to this site and others like it to gain a little knowledge before buying their parts for the combo, their efforts will be more successful than if they put a 90mm throttle body on their stock Stang and wondered why they didn't get any gain from their efforts.

Like modding Stangs, you just got to gather up a little knowledge to self tune and IMHO, it really don't mater which tuning interface you choose, that knowledge is gonna make you a better self tuner.

Later
Grady

 

[a50sn95]

I think the OEM tune is a BIG deal with these. Our cars (1994 actually) was supposed to have the new motor (the 4.6), as I understand it. Ford ran into some issues getting it together, and stuck the 5.0 in for 2 more years. I imagine they had this processor all ready to go for the 4.6, and then had to "adjust it" for the 5.0. They were already commited to the electric fan (which we all WANT) had OBD2 coming, stricter emmision standards, and now had to figure out a new processor for a car they didn't plan on producing. I think we got shortchanged a little in the "OEM tune" department.
That said, I think the entire problem lies with the limited knowledge available ABOUT the processor. It's a 2 year only deal. The A9L series ran for 7 years, and the "new" stuff has been in since '96, meaning the OBD2 processors have been produced in more numbers than the 87-95 processors combined.
My point is that if you are going to mod the car to the point that you need a tune (and you will...), why spend 500~ for a PIH conversion, if you can find one, and then 500~ for a chip/Tweecer?PMS...
At this point you could have just bought the Tweecer and been 500~ ahead.
I see a new PMS is 900 ish now, so now you're approaching AEM/BigStuff/used FAST territory at 1500.00.....

The Tweecer is still the best deal....

 

[5.0_GT_kid]

Awesome guys! Definetly a little of knowledge posted here in this thread and it's been a great help to me and hopefully others who read this thread.

I thank you all again for all your help, you guys make this the best place for tech info ever!!

 

[illwood]

Grady,

What's your opion on stand-alones like the AEM (pluses and minuses)? I had heard from naysayers that the piggyback tunes were just a bandaid fix and that the computer would start to accomadate for the lies it was told and eventually revert to a stock-ish tune. I have no idea on the validity of that statement, I'm just looking to have it debunked

StangNet = PCM Mythbusters

I'm planning on a 300+rwhp Mustang that still passes the MA emissions testing. I'm wondering if the AEM stand-alone or TwEECer would suit me best (so I love threads like this.)

 

[a50sn95]

I'd buy the AEM in a heartbeat if my budget allowed it. Plugs into the factory harness, uses the factory sensors, WB02 feedback, it'll practically tune itself.
It's technically, not legal though (At least in California...)
The Adaptive control inside the EEC is what you are talking about I think.
It will try to adjust the A/F ratio to whatever is in the computer, based on the O2's
You can turn it off, or go through the effort to get your injector slopes and MAF corrected so that there is no adjustment made.....
I'm still working on that....
A WB is almost a necessity.....

 

[final5-0]

Grady,

What's your opion on stand-alones like the AEM (pluses and minuses)? I had heard from naysayers that the piggyback tunes were just a bandaid fix and that the computer would start to accomadate for the lies it was told and eventually revert to a stock-ish tune. I have no idea on the validity of that statement, I'm just looking to have it debunked

StangNet = PCM Mythbusters

I'm planning on a 300+rwhp Mustang that still passes the MA emissions testing. I'm wondering if the AEM stand-alone or TwEECer would suit me best (so I love threads like this.)

Well Matt

The stand alone systems I've seen are kinda pricey, lol. I really don't know much about them. I do remember one of them claimed they could use the info from a wb and make adjustments for your final af ratio. Cool feature indeed!

Kinda Sorta along that same thought process is the PMS.

I don't know if the PMS would be considered a stand alone system but it is more of a user friendly system to use than the Tweecer/EEC Tuner. Again for that ease of use you have to pay more for the PMS. If you equip the PMS for data logging to allow for a fair apples to apples comparison with the Tweecer, the price difference becomes even greater.

If you don't know anything about the PMS you ought to check it out cause from what I've seen about it, it looks pretty slick. I have seen others say it doesn't give you as much access to the pcm as the Tweecer.

The Tweecer will not cause the pcm's adaptive strategy to make any changes or as you stated, it is not a bandaid fix. If you remove the interface from the service port, the pcm will revert back to its default Ford program.

Your goal of 300 or more to the wheels and still pass emissions testing is no prob as I have done the same myself although I haven't quite broken the 300 barrier, lol. I have passed Texas emissions testing for the past few years with no probs of any kind. I would also say that my drivability is stock like except for cam lope.

One of the strong points of the Tweecer is that you have access to most of the pcm's values to make the changes needed for drivability issues or as you pointed out, deal with emissions issues.

Hope that helps you some Matt cause I just don't know anymore, lol.

Later
Grady

 

[kck6894]

I have a PMS and it seems to work really well for me. I have been looking at the Tweecer web site and it looks like it is capeable of giving you more info than the PMS but it also says not all featuers work will all car/computers.

I've had my PMS since about '01 and have had good luck using it to tune. I know I have been at the track on several occasions where I was able to pick up 3-4 1/10th's and 2-3 mph in the 1/4. It never seems to fail that every winter I am changing something with the car and would have spent tons of money on chips.

From what I understand the piggy back systems run after the factory ECU. They take the data as it comes out of the factory computer, change how your tune requires, and then feed it to the engine/sensors. The new version of the PMS will let you go to stand-alone mode anytime after 2000 rpm. It's kinda cool when it switches too. It's like someone reached over and hit the NOS button!!

 

[illwood]

Grady,

That sounds reasonable (BTW, I love that you're getting all that power w/o a stroker or power adders). I have just started reading a bit about the PMS systems. I (like most people on this forum) am just trying to weigh my options so that I don't waste money on useless or overly expenxive mods.

a50sn95 I know what you mean about "technically" legal and illegal. If you run clean on the chassis dyno (non OBDII cars newer than 1983 get a semi-annual dyno smog test in MA) why should anyone care about the 1s and 0s in your computer? I imagine that custom cam grinds are technically illegal too because they never had a CARB EO number applied for (at the same time, who is going to ask to pull your cam and measure your lobes?) Trouble is that law-makers are not technical/engineering/physics/chemistry type people, but are lawyers who understand bureaucracy.

 

[final5-0]

Grady,

That sounds reasonable (BTW, I love that you're getting all that power w/o a stroker or power adders). I have just started reading a bit about the PMS systems. I (like most people on this forum) am just trying to weigh my options so that I don't waste money on useless or overly expenxive mods.

a50sn95 I know what you mean about "technically" legal and illegal. If you run clean on the chassis dyno (non OBDII cars newer than 1983 get a semi-annual dyno smog test in MA) why should anyone care about the 1s and 0s in your computer? I imagine that custom cam grinds are technically illegal too because they never had a CARB EO number applied for (at the same time, who is going to ask to pull your cam and measure your lobes?) Trouble is that law-makers are not technical/engineering/physics/chemistry type people, but are lawyers who understand bureaucracy.

I live between Fort Worth & Dallas and in my aera, they put your car on a mini dyno roller thingy to check your emissions with a sniffer up the tailpipe and the whole nine yards.

Even though they see all of the hot rod parts they never ask for any carb numbers but they do make sure all of the emissions stuff is there including cats.

For the past several years the guy said my car put out numbers they were way cleaner than the average car.

My cam causes a bit of lope and the lsa is kinda small but still, no probs with passing Texas emissions testing.

This past year I got another clean bill of health for the Stang even though I forgot to enable my egr. I have its input to the pcm on a toggle with my wb input and I had been doing a little testing a few days before I got the sticker but forget to put things back to normal, lol.

Later
Grady

 

[vyal]

I think the only major complaint that people have with these computers is that they seem to be a little bit more sensitive to vacuum or lack thereof then the A9L processors. You can tune around this but it just takes a little time. I just recently did a HCI swap and with the stock J4J1 tune the motor fired right up and would idle steadily at 900rpm once it was ajusted. The only 2 issues i have is that it seems to run a bit rich and it bucks just barely under 2000rpm with a closed throttle. Both can be tuned out its just gonna take me some time. I was just supprised how well this car runs and i havnt done anything more then change some timing numbers. Dont let people tell you these comps suck

 

[rude_life]

Wow. I really feel like a newby after reading everything in this post.

 

[rude_life]

OK so... In a way, what I am getting from this thread is that, The SN95 computer was doomed to fail from the factory, in turn sending us all on a quick trip to ping-city and providing the many o' stang owner endless amounts of what and why pertaining to the reason our cars run hot and just pretty much run like chit? If this is true, in any form of the word, why dont we just tell everyone with a ping, overheating, timing or fuel economy question to go and get a custom tune or a TwEECer?


Kris

 

[5.0_GT_kid]

OK so... In a way, what I am getting from this thread is that, The SN95 computer was doomed to fail from the factory, in turn sending us all on a quick trip to ping-city and providing the many o' stang owner endless amounts of what and why pertaining to the reason our cars run hot and just pretty much run like chit? If this is true, in any form of the word, why dont we just tell everyone with a ping, overheating, timing or fuel economy question to go and get a custom tune or a TwEECer?


Kris

That's a good question.

 

[final5-0]

OK so... In a way, what I am getting from this thread is that, The SN95 computer was doomed to fail from the factory, in turn sending us all on a quick trip to ping-city and providing the many o' stang owner endless amounts of what and why pertaining to the reason our cars run hot and just pretty much run like chit? If this is true, in any form of the word, why dont we just tell everyone with a ping, overheating, timing or fuel economy question to go and get a custom tune or a TwEECer?


Kris

Man O Man Kris

Your covering a lot of topics in one post

Overheating

I don't think its fair to push high ect's over on the pcm values Ford gave us. Some of those probs are nothing more than the system is getting to be 10 or more years old. The bulk of these probs are simply nothing more than we produce much more heat with all of the hot rod parts we bolt on our Stangs.

Ping Thing

While it is true that the pcm calibration file (the GT that is) Ford gave us is more prone to ping, some folks have had sucess with various methods which are less costly than getting involved with a custom tune.

Chit like performance

Lots of peeps get pretty good performance from their cars without a custom tune although I do think they would get more with one.

Chip/Tweecer

The reason these tuning methods are not more widely used is simply the cost.
I'm not gonna go into the detalis of the investment but it is more than most want to spend.

You see it all the time in threads like ... which cam makes a kazillion hp but doesn't cause the pcm to hose things up??? This thinking makes no sense at all cause everybody knows you should pick the parts that will do what you want the car to do and tune it by whatever methods are needed to make it all happen.

But ...... In the Real World ....................

Most tune by changing the fuel pressure and twisting the dizzy and with good reason ............... its much, much cheaper than a custom tune.

If you try to tell peeps to go for a custom tune to solve their combo issues its not gonna be too well received because of the cost, plain & simple.

In the long run, I think self tuning gives a person the most options who wants to mod his Stang.

IMHO, the Tweecer is the most bang for the buck.

That buck is bigger than most think and that is the problem.

Later
Grady

 

[a50sn95]

Final5-0 beat me to the punch, but I'm gonna say the same thing. For 90% of the 94-95's on the road the Stock PCM is just fine. Alot of the issues you are bringing up can sometimes be fixed by other means.
If your timing is set to 10 degrees and you still have pinging issues, what is your water temperature, or your fuel pressure? When was the last time you changed your fuel filter? When did you change your air filter? I'm just saying that there are probably other things going on that can also affect these things.....
The point of the Tweecer is when you get enough changes in airflow to the engine that it gets beyond the PCM's ability to adjust for the new changes. The adaptive strategy only goes so far. It's alot of money to just pull out 2 degrees of timing at 90% load to get rid of pinging.
The idea that our processors are inferior to the A9L is kind of unfair. It's more about the change in the way the processor determines things. Our processors are load based. So any time I change something that affects airflow, I'm altering the "load" that the PCM thinks the engine is operating in. Then it commands more timing or more fuel or opens the ISC al the way at idle, and it's still not enoguh for the new airflow. It's a little more complicated, and I assume it was primarily for fuel economy and emissions reason that they went to this effort.
Again, they were only used for 2 years, so the amount of people that understand them (And I'm not saying I do...) are far less than with the A9L series.
Finally, I guess my point is that if you make the switch to the PIH, and then end up with a chip ot other device to change some parameter, then you've just spent a S***LOAD of money to get something you could have done without the PIH.
Please note this is just my opinion....

 

[18mustangs]

Even though they see all of the hot rod parts they never ask for any carb numbers but they do make sure all of the emissions stuff is there including cats.

Probably because CARB means California Air Review Board Grady! Leave it to California to have extra stringent requirements.

 

[final5-0]

Probably because CARB means California Air Review Board Grady! Leave it to California to have extra stringent requirements.

Well take it for what it is worth but ...... the emissions tech told me the last time I got mine inspected that Texas was just as srtict as Cali. He told me that in the last year Texas had really cracked down on things.

Later
Grady