1G Help Identify ECU EPROM or not?

[sweet97]

I did a search because somewhere I was shown a pic of the inside of an ECU with info on identifying whether it is an eprom ECU. Well I fially got the ECU open. first some history. Why are some ECU's with eproms and some not? What extra value does an eprom add to an ECU? I have one from my '91 parts car (5-speedAWD). It's # MD 166262. If I can get some info/answers to these qustions it will be much appreciated. Oh, I also see a stage 3 eprom mentioned. Who sells this and what is socketing? sorry for so many ???????????!!!!! Mark

 

[SexyDSM95]

I did a search because somewhere I was shown a pic of the inside of an ECU with info on identifying whether it is an eprom ECU. Well I fially got the ECU open. first some history. Why are some ECU's with eproms and some not? What extra value does an eprom add to an ECU? I have one from my '91 parts car (5-speedAWD). It's # MD 166262. If I can get some info/answers to these qustions it will be much appreciated. Oh, I also see a stage 3 eprom mentioned. Who sells this and what is socketing? sorry for so many ???????????!!!!! Mark

What happens is early production cars came with EPROM ECU. My later production vehicle ( ), unfortunately did not come with EPROM ECU. It is valuable to a lot of us for the fact that we can add on performance chips and bypass a lot of restrictions set by the manufacturer. Also...it's a lot easier to socket for DSMLink so you wouldn't have to purchase an EPROM ECU then on top of that DSMLink. Save yourself $250.

 

[sweet97]

Thanks for the candid answer. Then this is probably worth $175. but I should identify the unit in my '93 to see what it is before I entertain the notion to sell this ECU. I am not familiar with DSM link though I have heard of it. My '93 AWD has many little things showing that a previous owner had tinkered with it. I believe the ECU was once accessed because one of the side skirts of the console is loose. Most of the emission vac lines have been removed. I want to get the EGR functional and may be able to now with the parts car. So much to learn!

Another question. It sounds like there are performance EPROMs available that will plug in the place of this stock EPROM. If that is correct who sells them and what EPROM replacement is considered to be the best?

mark

 

[David15151]

If you had a 2g you could use a 95 EPROM ECU to plug with DSMlink. I am not sure about how to do it with a 1st gen if its possible. DSMlink is a great system for tuning and logging. Pretty much the best for the money. Just have to get that ECU. They take out the chip.. put their own chip in. Socket it to allow you to plug your CPU up with the OBCII system.

 

[SexyDSM95]

!!!!!!! Another question. it sounds like there are performance eproms available that will plug in the place of this stock eprom. If that is correct who sells them and what eprom replacement is considered to be the best? mark

That is correct keep in mind that a lot of the upgrade chips will not increase horsepower. As I said before, they are mainly to bypass restrictions and log data. Like he said above DSMLink lets you tune/log data better then SAFC but not as great as a stand alone such as AEM would. More of an in between that is perfect for many of us who just want to tune/log from a laptop. Companies that do sell chips for the eprom ecu are VPC, TMO, DSMLink, and that's all I can think of off the top of my head. In order to definately KNOW if you have EPROM there would be like a black piece on the edge of the ECU...just go to dsmlink.com and there is a picture and what not to better describe/picture.

 

[kyledykstra]

That is correct keep in mind that a lot of the upgrade chips will not increase horsepower. As I said before, they are mainly to bypass restrictions and log data. Like he said above DSMLink lets you tune/log data better then SAFC but not as great as a stand alone such as AEM would. More of an in between that is perfect for many of us who just want to tune/log from a laptop. Companies that do sell chips for the eprom ecu are VPC, TMO, DSMLink, and that's all I can think of off the top of my head. In order to definately KNOW if you have EPROM there would be like a black piece on the edge of the ECU...just go to dsmlink.com and there is a picture and what not to better describe/picture.

But, DSMlink isn't out yet for the 1G's, (soon, *prays*). If the '91 is an EPROM ECU, and the '93 isn't, I'd put the '91 ECU in the '93 for that future day if (when?) you decide to go with an EPROM from some company. I had been running an SAFC and was about to get a TMO chip when I read on here that DSMlink was planning on getting their 1G version out before the end of the year, so I'm holding off myself.

There is no real answer to what's the best, it's up to you. SAFC + TMO + seperate logger works for quite a few people I know, the 2G people I know with DSMlink love it, the people with AEM standalone also love it. Compare all the options and decide how much more money you wanna spend on your DSM

 

[steve]

That is correct keep in mind that a lot of the upgrade chips will not increase horsepower.

Most of the upgrade chips don't directly increase horsepower. They remove limits that keep you from getting more HP like removing fuel cut/raising the rev limiter or add features like different uses for the stock "boost" gauge/adding a stutterbox for launching. Fuel injector correction can help performance by getting you back onto the correct fuel and timing maps. Changes to the fuel and timing maps haven't seen much dyno testing at this point so any changes tend to be for specific peoples cars and not a general offering.

Here's a 1G EPROM ECU from a '93 AWD that had some capacator leakage before repairing and socketing it.

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Steve

 

[sweet97]

Part # MD 145903 was produced from 3/89 to 6/90 so maybe my '93 does not have an EPROM but either way I will try to sell this eprom ECU. Thanks, mark

 

[steve]

Mark,

Where does the '90 MD145903 fit into all this?
I thought you said you had a MD166262 and your '93 should have a MD193299, MD193295, MD193300, or MD193296 depending on Federal/California and MT/AT

The picture I posted was of a '93 MD193299 EPROM ECU, so they are out there.

Steve

 

[sweet97]

Steve the email notice I received showed the link I cannot access and lists a damaged 145903. I could not access it due an incomplete address I believe. The link you posted previos to your last had the link I could not access. My '93 was built in October of '92 and my records show that it should have a # of MD of 166262. That's the same part # I pulled from the '91 parts car, again records show that 6/90 had a possibility of either a 145903 or the 166262.
So my'93 may have an EPROM or not? Or are all 166262's EPROM ECU's? Sorry if I am confused on the available part #'s as I have a list of 5 ECU's from 3/89 to 5/94 so I assumed that these are for AWD 5-speeds only.
It seems as though they are not as rare as I thought earlier. I use the MAF-Translator and don't see any advantage to me presently to use an EPROM ECU. Possibly a stutterbox function but can't that be done with an add on system/components? Mark

 

[steve]

Steve the email notice I received showed the link I cannot access and lists a damaged 145903. I could not access it due an incomplete address I believe. The link you posted previos to your last had the link I could not access.

Thanks, I gave that picture the wrong part name. It really is a MD193299. I'll make sure to change it.
My original post had a typo, I have no problem accessing the link above. Let me know if you do.

My '93 was built in October of '92 and my records show that it should have a # of MD of 166262. That's the same part # I pulled from the '91 parts car, again records show that 6/90 had a possibility of either a 145903 or the 166262.

I don't know where your getting your records from but I see the confusion. What your missing is the full build date. Your 10/92 car is a '93 model year and the MD166262 was used in '91 and '92 model cars built between the second third of June 1990 and the last third of June 1992. MD193299 was used in '93 model cars built between the first third of July 1992 and the last third of May 1993. MD14903 for reference was used in car made between first third of March 1989 and the first third of June 1990. Note there isn't any overlap. The place where there is multiple numbers has to do with the ECUs for different emissions and MT vs AT.

So my'93 may have an EPROM or not? Or are all 166262's EPROM ECU's? Sorry if I am confused on the available part #'s as I have a list of 5 ECU's from 3/89 to 5/94 so I assumed that these are for AWD 5-speeds only.
It seems as though they are not as rare as I thought earlier. I use the MAF-Translator and don't see any advantage to me presently to use an EPROM ECU. Possibly a stutterbox function but can't that be done with an add on system/components? Mark

I don't know, October is late enough in the production cycle for the Masked ROM versions of the ECU to be in use. We have found a limited number of EPROM versions from pretty much each ECU part number and to the best of my knowledge none were solely EPROM versions.

The big advantage to a EPROM with a MAFT is you can get fuel cut removed and you can get back onto correct fuel and timing maps for the engine load by having the injector size and deadtime corrected in the chip. Ask the guys who have run both ways, I think they will tell you that their car runs better correcting in the ECU than trying to with the MAFT.

Steve

 

[sweet97]

Steve I cannot access the link, it says no publsher given, but i use web TV! I guess that 6/92 did not overlap per say but the cut-off and change over to non EPROM ECU's was mid month as you stated. If I get 2 bills for mine I'll sell it otherwise I'll hang on to it. I gues just to change chips is posible, just pry up/out and replace. How do you go about getting a chip with the proper info burned into it? mark

 

[Dieselboy]

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Offtopic, but thats a L337 license plate!

 

[SexyDSM95]

How do you go about getting a chip with the proper info burned into it? mark

I think the proper term is "flashed" and not burned. I think it's the same process that a lot of satellite companies use to flash the SIM cards that you put on the back of your receiver.

 

[RoasT BeeF]

Lets not confuse the man here. He has a 1G not a 2G so stop talking about dsmlink. Yes it is supposed to come out soon for the 1G's but I dont think thats even what hes asking anyway. I believe he is thinking more along the lines of socketing the ECU for a chip? Basically what that means is you take out the original EPROM chip and solder in a socket. Then when you order a new chip either from TMO or dsmchips.com you can just plug it into the board and if needed swap back to your old original chip.

Take a look at www.dsmchips.com and look at the stage I, II, and III.

 

[steve]

I think the proper term is "flashed" and not burned.

Continuing on the tangent. The correct term depends on what type of chip is being used. Burned is ok in the general sense. Flashed is only correct if the chip in question is a Flash EEPROM (electrically erasable programable read only memory).
Burned dates back to the earliest PROMS where a fuse was actually burned away in the process of programming the chip. We still refer to burning a PROM as the process of programing the contents of the chip regardless of how. The 1G ECUs use a 27C128 or 27C256 EPROM from the factory or the compatable EEPROM aftermarket but can't program the chip in the ECU. So it has to be burned or flashed external to the ECU. New ECUs like the one in the EVO VIII can be flashed in the car.

I guess that 6/92 did not overlap per say but the cut-off and change over to non EPROM ECU's was mid month as you stated.

If I get 2 bills for mine I'll sell it otherwise I'll hang on to it.

I gues just to change chips is posible, just pry up/out and replace.

The change over was to the different part number ECU not from a EPROM to non-EPROM version although the early versions of the new ECU were EPROM versions just like the early versions of the prior part number were EPROM.

You should be able to get at least $200 for the EPROM ECU. Between $200 and $250 is the going rate and will only go up due to the limited supply and increased demand. You should be able to get $100-$150 for the non-EPROM ECU and what people are suggesting is you keep the EPROM version and sell the other rather than discover later you need one.

Before you can change the chip it has to be desoldered from the ECU board and a socket inserted. They you can pry up/out and replace as needed.

Steve