MORE ecm changeover questions

[fritz]

Guess us newbies beat this topic up pretty good.
Put the ecm (used from a yard, you know the guy said it was good???). Followed the instructions properly. First start up...ran rich lots of garage filling black smoke.
1. can I assume the 86-87 ecm to be good since the car started, but ran rich??
2. Borrowed a 87 AC MAF from a friend....no change(friend thought MAf is OK)
more black smoke
3.FYI... changed cal pac out from my 84 ecm. Tried the chip that came with the ecm. then put in my new Eric chip, still more black smoke
4. Am I headed for "Translater Land" to fix this. Anyone know of any deals for the Translater

Mods;Tomco green stripe 30#. Gut convertor.Big Mouth cold air kit. Hv fuel pump/hot wire. Dented stock FP reg to 46# line off

thanx for your help

 

[6SENSE]

ECM is #1227148?

any codes?
o2's?
blm, int #s?
af #s?
chip burned for your injectors?
46psi static fp is pretty high for our cars.

 

[Squid4life]

I didn't see anything about the MAT sensor being installed... Stupid question, but you did install the MAT, right?

Squid

 

[Bryan C.]

Turn down the fuel pressure. Try starting at 38#, you may still have to go down from there but it should help alot.

 

[fritz]

Responses

7148 ecm-yes
Turbo link -just came in, stillwaiting for new laptop, so I have no diag. info yet.

tried the stock 87 chip, then tried the new eric chip burned for my set up.

dented the stock FP reg to get the pressure, new adjustable one on the way(car seemed to like the 46# pressure with the stock 84 ecm & chip)

mat sensor installed & correctly wired to ecm harness

Looks like first thing to do will be Fuel press. to 38#

What are you guys thoughts about translator/LT 1 MAF set up. If it looks like it should be the direction
I'll end up going to, then maybe I should do it now???

 

[fritz]

X

any body?

 

[Bryan C.]

If it works with the current maf, I would wait. My car ran rich and had issues with the stock maf, so I changed over to the LT1 maf and translator.

 

[6SENSE]

Ultimately the translator is the way to go. I havent seen a replacement maf that lasts long yet. Usually just long enough for the warranty to expire . The "good" oe mafs are sometime going to be obsolete other than those on very low mileage cars. Sooner or later everyone is probably going to be using a translator, which isnt a bad thing because they work well and the maf used with them isnt going anywhere because its used on dozens of vehicles (not just LT1). Just my 2cents.

Also, the MAT sensor would not cause the issues your having. You can unhook your MAT sensor and the worst thing that would happen would be seeing the ses light.

 

[fritz]

still not working

finally put on the fuel pressure reg. turned down to 38#...still rich,,. borrowed another MAF from a friend(this makes 2) still rich. Had to re install the stock 84 ecm, chip, maf. to get the thing to run right & clear the cyls.

If the 86 87 ecm i got from the yard is bad, would the motor even start?

Looking like I;ll have to go the translator route??? Think a LT1 MAF from the yard($50.00) is a poor choice?? New from GM it's 213.00 list, my price 168.00

To add to the fun, tried to run the car with turbo link i borrowed from a friend, now it's not working right....keeps loosing the connection. said to chech cables , which i did...still no go

Tell me when I'm having fun!!!!!!!!!!

 

[Bryan C.]

It is all fun! Of course you may not think so right now. You may need to adjust your fuel pressure down even lower. I have seen people running as little as 32#, your 30# injectors are going to feed more fuel than the stockers at the same pressure. I would put in the TurboTweak chip and keep adjusting your fuel pressure. Adjust it down in 2# increments and see if it finds a happy spot.

An LT1 maf for $50 is not bad, I would buy it. You may check Ebay as well, I was able to get mine for $15. HTH.

 

[fritz]

The 30# injectors have been in the motor for a month now. Ran pretty good at 46# & the 84 ecm / stock chip.
I'll try the fp lowered as you suggested 2# at a time tommorow.

 

[6SENSE]

Should run fine with 38#, should run fine with 42#..... fp is not the issue. I would try another 87 ecm. Yes it will start up with a faulty ecm (depends on what is the problem with the ecm). Your tlink not working correctly, if you installed correctly, may be an indication of the ecm being faulty.

Yes, you should be using the chip that was burned for the injectors, however.... 30# injectors are bigger than the stockers @ 28#, but not huge injectors. They [green stripes] are often considered stock replacements in the TR community. Still dont think that even with the stock chip those injectors will have the car running that bad.

Have you tried the 84 maf with the 87 ecm? That may tell you if you have a problem with the 87 maf. The car will run okay with a 84 maf and a 87 ecm although calibration of the maf is a bit off.

I was going to suggest to start addressing possibe ignition fault, i.e. wires, module, coil, etc. but you say that the car runs fine with 84 ecm. So, switch the mafs and then try another ecm or two. They dont cost much from the junkyard and its good to have an extra or two anyway.

P.S. Also, which Tlink version do you have? If it is one of the newer versions (newer than v2.13) you have the two LEDs on the cable that will let you know if it is powered up and if info is/can pass through.
AND, check for trouble codes manually through ALDL plug under dash with paperclip,etc. make sure you have a code 12 for the ecm functioning (still could be bad though) and see if there may be the infamous code 42 (faulty est circuit).

 

[fritz]

Just a quick THANX to you guys for taking the time to come back with help info.

Fuel Pressure....tried at 36, 38, 42..no change. In Eric Marshell info that came with the chiphe indicated to run 42. By the way he did the chip per current spec for the motor

Tlink---tried it with the 84ecm/84 in the software setup, loosing connectionto ecm
then we tried it / the 86-87 ecm(eric chip) again loosing connection
Tlink has 1 green led which would flash on & off....with the connection. I'm working on a solution for that problem. so I can use the dang thing.

Green injectors.....seemed to work welll with the stock 84 config.

MAF... 84-ran rich poor idle- un driveable
87(#1) bad rich
87(#2) better, but still rich

Ignition.. new 1 month old 86-87 coil/ adaptor & 86 87 ign. mod.
new plugs
wires, less than 2000 mi

Codes... none

 

[6SENSE]

Youve narrowed down things a bit even without a scantool. If it were me Id go for another 1227148 ecm.
Let us know when you get Tlink up and running too.



p.s. Should always get at least a code 12 when grounding aldl ports b and a. This tells you that the ecms diagnostic system is working.

 

[fritz]

code 12

Yes there is a code 12. I didn't reralize it is also is a code. Thought it was just a start indicator for diag mode.
So, with the code 12 present, do you still think I should try another 1227148?

 

[Jerryl]

Yes there is a code 12. I didn't reralize it is also is a code. Thought it was just a start indicator for diag mode.
So, with the code 12 present, do you still think I should try another 1227148?

From GNTTYPE
http://www.gnttype.org/maint/malf.html#12


CODE 12

Trouble Code 12 is a special case code that is not logged into the ECM's Non-Volatile Memory (NVM) when detected. When the ignition is "ON" and the ECM detects no ignition reference pulses coming from the ignition module, it illuminates the Service Engine Soon lamp.

Code 12 is also used when the ECM is in Diagnostic mode (ALDL Terminal B grounded, key On, engine Off) to signal the beginning or end of a so-called 'diagnostic sequence'. This is when the ECM enunciates each stored code using the instrument panel Service Engine Soon lamp.

When in this mode, the ECM will begin by flashing code 12 (on the lamp) 3 times. This indicates the beginning of a diagnostic sequence. It will then flash any codes stored in NVM 3 times each before proceeding to the next code. When all stored codes have been displayed, the ECM will again flash code 12 to indicate the end of the diagnostic sequence. The cycle continues as long as the ECM is in Diagnostic Mode.

NOTE: The codes will not be displayed in order of occurrence but rather in numerical order.

 

[6SENSE]

Yes there is a code 12. I didn't reralize it is also is a code. Thought it was just a start indicator for diag mode.
So, with the code 12 present, do you still think I should try another 1227148?

Just looking for the obvious first. If you are getting code 12 then great, but I wouldnt assume the ecm is 100% just yet. Assumed that a long time ago and went looking elsewhere only to wind up replacing the ecm anyway. It just means the diagnostic portion is working.
Also from gnttype.org :

3. The ECM will cause the "Service Engine Soon" light to flash Code 12, indicating that the ECM diagnostics are working. Code 12 will flash three (3) times, followed by any other trouble codes stored in memory. Each additional code will flash three (3) times, starting with the lowest code, and then start over again with Code 12. If there are no other codes, Code 12 will flash until the diagnostic jumper is disconnected or the engine is started.

Like I said wont hurt to try another ecm, worst comes to worst youve got a spare which is always a good idea anyway.
What about the 87 maf you borrowed? Does that person have a known good 86/87 ecm you could try?

 

[fritz]

OK I'm out of friends with spare MAF to loan me. So looks like I'll try to get to a yard tommorow on my lunch, to try to locate another 7148 ECM. Don't know when i'll get it installed, so check back on this thread when you can
thanx

 

[fritz]

2nd ecm

Just tried a 2nd used 7148 ecm. Problem still identical. Tried the 2 87 MAF & my 84 MAF. Still running "bad rich". My guess is the ecm are ok. Logical to suspect the MAF.
Time to start thinking about translator/LT1 purchase??
By the way called Ken at turbo link, he felt quite strong that the connection problem is in the usb/serial adaptor. he gave me a few suggestions on what to look for in a replacement. He also ssuggested the Zo6 MAF
(gm #25318411) I'm wearing out the numbers on my credit card

 

[turbo6x2]

Ken Mosher is a really great person to do business with and can usually pin point any issues. Top notch vendor all the way.