Did you get a chance to unplug the wheel speed sensors to discover the results?
When we started this particular conversion, the OBDII PCM was sent off to have the EBTCM/UART inputs programmed out of it to avoid these issues. So, we didn't keep any of the other modules or sensors that were in the donor car--turns out that was a big mistake, huh! I do have the climate control unit which has the display for reading codes. However, we just use a typical scanner on the DLC to find, clear and resolve codes.
In hind sight, those who want to do this swap (and want to use the automatic tranny) should use the 1995 and earlier PCM if you want to stay close to stock as possible. Minor issues to resolve compared to OBDII.
It will eventually get sorted out in the long-term. BUT I am disappointed with the PCM re-programmers out there that advertise that they have a working computer & tune for OBDII N*. They should not sell or advertise a PCM's with a recalibration or tune that doesn't work properly. It displays the inexperience these companies have with their "as advertised" products regarding the Northstar engine.
My local dyno/tuning guy told me that I will have to do about twenty of these N* conversions before I discover a tune that works well. He said next time do an LS V8 because there's lots of them in other cars/platforms and they are easy to tune/calibrate!
Oh, well. I still like the N* and am going to get it to work eventually.
When we started this particular conversion, the OBDII PCM was sent off to have the EBTCM/UART inputs programmed out of it to avoid these issues.
It will eventually get sorted out in the long-term. BUT I am disappointed with the PCM re-programmers out there that advertise that they have a working computer & tune for OBDII N*. They should not sell or advertise a PCM's with a recalibration or tune that doesn't work properly. It displays the inexperience these companies have with their "as advertised" products regarding the Northstar engine.
The "programming inputs out" is a very risky claim to make on the part of a reverse engineering outfit. They're obviously chasing the business before they'll be will to really do the R&D. I assume that you have gone back to them either for your money back or discounts on updates?
For example, if the communications are turned off, but the routine that checks the data received from external modules is not turned off, then it will still set the code when it doesn't receive communication, only now there's no way to get it that communication. The programmers are shooting in the dark and will need a lot of iterations in order to get it right, without the source code or an understanding of how the software system is architected.
Yes, went back to the supplier. They have been very nice about it but unable to arrive at the solution currently.
I'm considering re-pinning the harness to the 95 computer. I have two of them. I'm told also that the memcal chip can be altered so the inputs are not necessary in the OBDI unit. I also have another stock untouched OBDII computer. I also have an LS1 computer as well that runs my manual N*(with an unresolved problem tune).
I wonder if an OBD1 EBTCM would work for the OBDII computer?
You would have same issue as now... I would guess you would be fine with the obd2 computer and obd1 ebtcm but you still going to need what ever translates the uart wires to class 2 serial data, so I do not see that being any help.. If you are using the vendor I'm thinking they tried the same for someone else and could never get it right even with obd1. look into getting the uart to serial data working and I Wil bet wiring up that with the Ebtcm you will be good to go... I am off Friday and will try disconnecting the was and post results
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a Northstar Rebuild
[This message has been edited by jb1 (edited 01-22-2014).]
Question: Can a memcal chip, in the OBDI computer, be copied or duplicated? Can the contents of the chip be copied or transferred to a blank chip with a chip burner?
Regarding my LS1 Computer, it is running the Shelby program on my manual 96 N*.
Regarding OBDII 1996 diagrams, there is no connection showing the tan UART wire directly or indirectly connecting to the purple Class 2 Data line. Only the white wire is shown as a "data" line to the instrument panel (I believe its a simple light that comes on designating the anti lock status). I don't have the gauge pod assembly from the Caddy.
There's a caddy at the local wrecking yard. Maybe I will think about finding the body control module that translates everything on the UART tan line and see if that makes a difference.
[This message has been edited by IXSLR8 (edited 01-23-2014).]
Question: Can a memcal chip, in the OBDI computer, be copied or duplicated? Can the contents of the chip be copied or transferred to a blank chip with a chip burner?
Regarding my LS1 Computer, it is running the Shelby program on my manual 96 N*.
Regarding OBDII 1996 diagrams, there is no connection showing the tan UART wire directly or indirectly connecting to the purple Class 2 Data line. Only the white wire is shown as a "data" line to the instrument panel (I believe its a simple light that comes on designating the anti lock status). I don't have the gauge pod assembly from the Caddy.
There's a caddy at the local wrecking yard. Maybe I will think about finding the body control module that translates everything on the UART tan line and see if that makes a difference.
answer to question is yes it can be copied, talk to Darthfiero. If it is the bcm (PZM, from what I have read tonight it is what translates it) that translates the UART to serial data that would be what it should need. If I disconnect my ebtcm I loose 1st gear, so the ebtcm is the main factor there. If it is not connected to your PCM somehow there is no way it will work, because the code I had that cause the 2nd gear starts was loss of data. From what I have found on the 96 the loss of data is a PZ2042 - No Response from Traction Control to UART Messages and PC1602 - Loss of EBTCM Serial Data. I think you add the PZM,bcm whatever you want to call it and it should solve most of the problem, I will disconnect the wss and post friday night.
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a Northstar Rebuild
He doesn't really know what the modded computer has in it... It might still have a problem even when it's wired up correctly. Best to use the stock computer when trying to figure out "swapology" issues like this.
quote
Originally posted by IXSLR8:
Regarding OBDII 1996 diagrams, there is no connection showing the tan UART wire directly or indirectly connecting to the purple Class 2 Data line. Only the white wire is shown as a "data" line to the instrument panel (I believe its a simple light that comes on designating the anti lock status). I don't have the gauge pod assembly from the Caddy.
There's a caddy at the local wrecking yard. Maybe I will think about finding the body control module that translates everything on the UART tan line and see if that makes a difference.
"sounds like" whatever path data has to take to get from the EBTCM to the PCM needs to be complete. If that's going through the BCM as a bus gateway between the two buses, then that's what it will have to be.
Went to the wrecking yard and found a 1996 Body Control Module. It has a ton of wires coming out of it including, guess what?, the tan UART and purple class 2 wires. The GM diagrams show the tan wire on one diagram without the purple class 2; and visa-versa. That's why I was unable to see the crossover right away. So, it looks like the signal must get cross fed to the other side through the Body Control Module.
My gut instinct is that I'm going to need all three of the other UART modules and their sensor counterparts to not throw codes. If so, I will probably not pursue it any further using the OBDII computer additionals. I hope that the PCM supplier can finally produce a calibration or reprogram for that side of the controls.
If that doesn't happen, then I will pursue my secret weapon!
I agree. MOST LIKELY is that the combo of the EBTCM and BCM in the car will satisfy the PCM's tendency to throw codes and do second gear start.
If nothing else, just tuck them away where the blower motor for the alternator and coil cooling ducts used to be... They *should* only have to be wired up to power, ground and data.
EBTCM and PZM wired up along with class 2 data line to the PCM. No difference what so ever. The PCM internal changes probably are affecting the outcome.
We swapped another 1996 Caddy computer and it would not fire or start.
would guess it would be paskey issue on the 2nd pcm, and if everything is turned off or deleted no wonder the 2nd will not work. you need a pcm with passkey turned off but all the others left alone.. Unfortunately that is the only way I can see it working out for you. was looking for an update. Im still waiting for a decent day to take car down road without wss, it is 7 degrees right now...
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a Northstar Rebuild
[This message has been edited by jb1 (edited 01-29-2014).]
I have the passkey module mounted in my car with the original key thought it would be good secondary security... never take the original key out so there goes that idea..lol I know you spent a lot of cash on programming and I started to go same route and sent a couple emails back and forth with a vendor claiming to be able to do exactly what I need, but he stopped replying and another member said he paid and never could get it right so I went the route that fixed my issue, which was the ebtcm. search net there are only 15 different resistors used on the vats system, If I am not mistaken up to 99 still used the Vats with resistor in key, problem being the module was built into the IPC.. so you may have to have try and send another pcm to you vendor and get them to only turn it off and leave everything else alone.. Hopefully they will take care of you because im guessing you spent quiet a bit on programming that did not work.
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a Northstar Rebuild
[This message has been edited by jb1 (edited 01-29-2014).]
Hi, I am having some same problems like the 2 gear start as well. Will gave me a like to this thread, thanks Will. I am new here so I am sorry that I am not clear on some of the chat that is being said. I am going back and reading all the comments here but sorry if I retouch on something that has been talked about.
I have a 1989 replica Lamborghini Countach built on a 1985 Fiero, it has a 1993 n* with the 4t80e I bought this car as it was I have had to do the head gaskets in it.
problems:
wont idle it starts fine and if I keep giving it gas it will stay running as soon as I let gas off dies when its warm it will idle but goes to almost dying to 1300 rpm
no power
I cant even spin the tires on gravel
wont shift
I can get to about 70km but wont shift past there engine is at a very high rpm when I am doing about 50km and let off gas its like it goes into neutral rpm goes down to almost stalling then shoots up to 1000-1200 rpm and back down when I give it gas again I have to get rpms back up before trany engages again
it has been wired to piggy back the fiero computer as well. I am going to fix that
Originally posted by Dave_m: I can get to about 70km but wont shift past there engine is at a very high rpm when I am doing about 50km and let off gas its like it goes into neutral rpm goes down to almost stalling then shoots up to 1000-1200 rpm and back down when I give it gas again I have to get rpms back up before trany engages again
it has been wired to piggy back the fiero computer as well. I am going to fix that
As I mentioned in the other thread, this sounds like the trans is staying in 1st gear, not 2nd, as the transmission won't have any overrun in 1st with the shifter in D. That's a characteristic of the Simpson gearset.
do you have an ipc wired to check codes? you need to get it running first.. what about the brake switch for tcc ? the 4t80e is bad about cracked shift solenoids and could very well be an issue.. get and ipc wired up pull all the codes current and history and post them and we can walk through them to get it running right first..
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a Northstar Rebuild
I do have the dash from the doner installed in the car and it has engine light on and tells me trac disabled so i do know there is codes to be seen. I dont know if i have a place to plug into it i have not seen one so do i just wire it to the computer. I do have the wiring diagrams for fiero and seville any obd1 plug
[This message has been edited by Dave_m (edited 01-29-2014).]
wire it to computer. it. will always show Trac disabled. I will post more in early am after work. and when I can set and read ur full post and issues instead of on phone..
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a Northstar Rebuild
I do have the dash from the doner installed in the car and it has engine light on and tells me trac disabled so i do know there is codes to be seen. I dont know if i have a place to plug into it i have not seen one so do i just wire it to the computer. I do have the wiring diagrams for fiero and seville any obd1 plug
Press and hold "Off" and "Warmer" on the IPC simultaneously for several seconds. It will enter a diagnostic mode in which it *should* be able to tell you what codes are current (*IF* it is wired to the engine computer correctly).
[This message has been edited by Will (edited 01-29-2014).]
I'm assuming in the OBDII application that the VATS information is passed to the ECM via data, rather than discrete connections as with OBDI?
IE, will a VATS eliminator work without the IPC?
I have the VATS eliminator circuit that I used on my 3800SC wired into the ECM (96 Aurora) wt 4t80e. I have a lot of things to work out yet, but starting and running is not an issue.
Hi there, I'm new here and this is my first post! I am 90% done with my northstar fiero and have come across the 2nd gear start issue... I have a northstar out of a 99 sts, as far as modules that talk to each other via class 2, I have the gauge cluster, rear integration module ( solely to make the fuel gauge work ) and the dash integration module ( ac, heater control ) , that's it... in order to make it run, I sent the pcm to westers and he tuned it for; security off, traction control off and shift points and other currently irrelevant things, but it still has 2nd gear starts... when I talked to him last, he said he was going to look into trying to be able to tune it for first gear starts with my set up... the questions I have for you guys are; have any of you gone through the tune method of resolving the 2nd gear starts? And/or is there now a common consensus that you guys could give a simplified checklist of what's necessary to make the obd2 "northstar system" happy to function correctly ? Any info would be greatly appreciated!
I wonder if you could use an older ebtcm since on the. ObdII ebtcm still uses uart. You will probably need the bcm to translate uart to serial data. Should be simple hookup. I hope you follow through it would be good to know if works for ones with obdII. As will stated wheel speed sensors are not needed. I found that out a bit to late
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a---sold Northstar Rebuild
Yes the 3 modules I have are from a 99 (one donor car) and I did try that although probably not thorough enough ( just twisted wires once to try ) and don't have it any more... later this week I'll go to the local u-pull-it and see if I can get the abs assembly from both an obd1 and obd2 car... as far as the body control module, I can't remember off the top of my head, where in the car is that module? I'll grab that too to wire up as you said to convert signals so hopefully everything talks to each other.... thanks for the responses!
We are still waiting on Westers for our 2nd gear start issue regarding the 85GT 1996, OBD2, Northstar.
I'm getting ready to start an 88 coupe and 1995 STS Northstar and 4T80e. This time, I will be using modified chips in the 93-95 computer. I have the cradle built and the engine mounted to it. Still have to do the bulk of the standard items such as axels, exhaust and plumbing, shifting cables, wiring, etc....
I think the way to go is with OBD2 (either LS1 or stock caddy computers). But until the 2nd gear starts are solved, I'm going OBD1 with modified chips.
[This message has been edited by IXSLR8 (edited 04-30-2014).]
I should mention that last time I talked to, AJ, he had a calibration for the 96-99 computers that solves the 2nd gear start. He said he's done several and no one has complained about 2nd gear starts. I just don't want to spend another $400 to see if his works.
We are still waiting on Westers for our 2nd gear start issue regarding the 85GT 1996, OBD2, Northstar.
I'm getting ready to start an 88 coupe and 1995 STS Northstar and 4T80e. This time, I will be using modified chips in the 93-95 computer. I think the way to go is with OBD2 (either LS1 or stock caddy computers). But until the 2nd gear starts are solved, I'm going OBD1 with modified chips.
Modified chip is not needed for the 95. I was sending my spare chip to ryan ( it is still in shipping box) to make me a copy until I used the ebtcm, $20 from pull a part and connect about 5 wires and you have bypassed the 2nd gear starts. If you have the donor just pull it out of the trunk and you are set. OBDI issue has been solved.
------------------
87GTseries 1 3800sc (7.597 @88.53 1.579 60ft) (series II swap in progress) 85GT Northstar/ 4t80e 86GT 3800 n/a---sold Northstar Rebuild
I think the way to go is with OBD2 (either LS1 or stock caddy computers). But until the 2nd gear starts are solved, I'm going OBD1 with modified chips.
Not sure if HP Tuners will do it, or if it would take EFI Live, but it may be possible to get the Shelby computer to control a 4T80E.
Modified chip is not needed for the 95. I was sending my spare chip to ryan ( it is still in shipping box) to make me a copy until I used the ebtcm, $20 from pull a part and connect about 5 wires and you have bypassed the 2nd gear starts. If you have the donor just pull it out of the trunk and you are set. OBDI issue has been solved.
So, did you get a chance to unplug the wheel sensors to see if it throws codes or affects the shifting?
It made no difference hooked up or not. I will leave them unhooked and tie them back to drive it all weekend and make sure not long term issue but it made no difference to unplug and drive down road and back.
I have this problem as well is a "Howell wiring harness" that the Data Link will not read codes. any and all help would be Greatly appreciated.
I have been looking at all your post, tried to email jB1 with no reply. All your post sound good, would like to get wiring diagrams and specific from jB1 on what parts are needed and how to wire it. I recently went to Cadillac and explain what I learn from all your post about installing the EBTCM to a 30 year Cadillac mechanic, he said you would not need the ebtcm INSTALLED . He said take a resistant reading from the ebtcm with a DVM what ever the resistant reads to install the proper value resister to the data wire and you will have first gear. I have not tried this yet but that would be fantastic if it works. Anyone have thoughts on this? Thanks
runs works perfect no 2nd gear starts.. pulls real good off the line 10x better than before From reading I found that if there is no communication between the ebtcm and the pcm it automatically diverts to 2nd gear starts.. I added wheel speed sensors and all on the rear then wired them with diodes and have no wheel speed sensor codes.. but it does show traction control disabled which is fine for me, I do not want traction control. I wonder if I would still have 1st gear even if I had not added the WSS, I am guessing I would be fine since the TCS is disabled.. I have wondered if anyone has ever tried to wire in just the EBTCM on the OBDII without the brake lines etc, I know the electrical part of the ebtcm is removable from the part where the brake lines attach.... It maybe the same as mine to where is in not actually looking for it to function properly as much as it is just looking for the communication... Hope that makes sense to you.
jb1 could you give a list of parts need other than the ebtcm if any? Wiring details (diagrams) if it should be wired directly to the pcm which pins? Can the ebtcm be hooked up without the pump? Also I have a Howell wiring harness that a data link does not work. Would you explain how to wire the IPC so it will work and read codes? What was all needed to complete this second gear fix?
