I did not use a BCM in this swap. Unfortunately, with it missing, the cruise control refuses to work (cruise control switch wires directly up to the ECM). The ECM is looking for a BPP (brake pedal position) sensor signal from the BCM - which there is none. The BPP only hooks up to the BCM in the LS4 applications. There is a stop lamp switch wire that hooks up to both the ECM and TCM and I have that hooked up (using the stock Fiero brake switch). Neither the ECM or TCM throws a code for a brake switch signal but the ECM must want to see BPP sensor status before it will enable cruise control operation. Reading ECM data with the Tech2 it shows BPP sensor status as "invalid" and thus cruise control operation is prohibited. TCC still works though.
I had a work-around planned using a stand-alone GM electromotive cruise control module hooked up to actuate the accelerator pedal assembly but the customer opted to NOT have me pursue that option.
FWIW: The BCM wasn't a mess in the 1st LS4 swap I did either - it served its purpose and worked for everything that customer wanted it to do.
[This message has been edited by Darth Fiero (edited 07-16-2013).]
Originally posted by fieroguru: Tom, care to share what kind of interstate mpg you are seeing? I know its hard to keep your foot out of it long enough to check the #'s but I am curious what you are seeing.
Unfortunately i don't have any concrete mpg at this moment, you know heavy foot syndrome (HFS). from my trip back from Indy to Texas, the first leg from Indy to Bowling Green, Ky which was cool in the morning so running w/o A/C and avg about 70mph i got 25.5 mpg. all the other fill ups with running A/C and avg 70+mph i got around 22.5. i think if i follow the posted speed limits and not have any HFS the mpg will be better but who am i kidding, I didn't get this swap for best mpg. i'm in Texas where some places the speed limits is 80mph and nobody follows that. i'm trying to see what my in town mpg will be, hopefully i can at least get that info.
[This message has been edited by Tom Slick (edited 07-16-2013).]
Come to Austin, you will be driving at least 5mph Under the speed limit
Its more like only going 5 mph the whole way. I just drove from Austin to Dallas last week, I-35 has so much road construction going on it took almost 4 hours for that drive. yuck~
Originally posted by Darth Fiero: FWIW: The BCM wasn't a mess in the 1st LS4 swap I did either - it served its purpose and worked for everything that customer wanted it to do.
It was completely not needed... the "BCM" functioned soley as a bypass not a feature. The fact that you can eliminate "100+ wires" from the swap using stock wiring makes the whole LS4 swap alot more viable. Was it just an HPT hack that allowed this? Is it specfic to any years?
It was completely not needed... the "BCM" functioned soley as a bypass not a feature. The fact that you can eliminate "100+ wires" from the swap using stock wiring makes the whole LS4 swap alot more viable. Was it just an HPT hack that allowed this? Is it specfic to any years?
The BCM IS needed if you want factory keyless entry, factory remote start, and the DIC from the donor car (in that case, an 05 GXP) to work in the Fiero. And apparently, you also need it if you want cruise control to work thru the LS4 ECM. That's what the 1st LS4 swap customer wanted - so I did as he asked. Yes, it was a lot of work to install that BCM into a Fiero and make everything work that he wanted, but I didn't have a problem with pulling it off.
In this latest LS4 swap I did, the customer did not want the BCM so that made the wiring part of the swap much easier. HP Tuners was used in the 1st swap because that was the only tuning software available at the time that could tune LS4 ECMs. But now TunerCat has rolled out support for many of the newer GM platforms, so I was able to use TunerCat to tune the latest swap which uses an 08 GXP LS4 ECM (E67) and TCM (T42) to work in a Fiero without a BCM.
Disabling VATS in these systems requires an OS patch which both HP Tuners and TunerCat can apply.
Besides the cruise control not working, I was also not able to do a CASE Learn because of the missing BPP sensor signal. Neither HP Tuners nor my GM Tech 2 scanner will allow the CASE Learn procedure to begin because of the missing brake pedal position data. So I had to disable misfire detection and the CASE Learn code. Interestingly enough though, I did some digging and found a GMPP E67 LS3 ECM program and found out that GM had misfire detection and the CASE Learn functions disabled in that programming, as shipped from the factory. Wiring diagrams for the GMPP E67 LS3 ECM show no brake pedal switch connection nor any cruise control switch connections whatsoever. So I guess if you buy a brand new LS3 crate motor from GM and get their pre-programmed E67 ECM with it, you are out of luck if you want cruise control.
Originally posted by Darth Fiero: So I guess if you buy a brand new LS3 crate motor from GM and get their pre-programmed E67 ECM with it, you are out of luck if you want cruise control.
Yes, that is why if you want CC and you get a new LS3 crate motor you have to use an aftermarket ECM/Harness. I was not using CC in my 88/LS376 swap so Archie could use the stock GMPP ECM/Harness, but a few of the local guys who wanted CC went with a setup from Street and Performance. In the end the S&P setup is better (IMO) becasue they strip out all the wires you don't need.
Originally posted by qwikgta: Yes, that is why if you want CC and you get a new LS3 crate motor you have to use an aftermarket ECM/Harness. I was not using CC in my 88/LS376 swap so Archie could use the stock GMPP ECM/Harness, but a few of the local guys who wanted CC went with a setup from Street and Performance. In the end the S&P setup is better (IMO) becasue they strip out all the wires you don't need.
Yes, that is why if you want CC and you get a new LS3 crate motor you have to use an aftermarket ECM/Harness. I was not using CC in my 88/LS376 swap so Archie could use the stock GMPP ECM/Harness, but a few of the local guys who wanted CC went with a setup from Street and Performance. In the end the S&P setup is better (IMO) becasue they strip out all the wires you don't need.
Rob
Since using an aftermarket ECU is a requirement, I have to assume it won't communicate with the GM TCM that runs the 4T65-E trans in this swap WHICH MEANS you would also need to buy an aftermarket transmission controller (TCU). Sounds like using the aftermarket stuff is going to be quite expensive (and I bet the aftermarket modules are nowhere near as reliable or capable as the factory GM modules – based on the past experience I’ve had with them).
I think it would be cheaper to just install a GM electromotive cruise control unit to actuate the accelerator pedal in this swap directly.
That looks like a much better option than switching out to an aftermarket ECU and TCU. Probably much cheaper too. If you call them, tell them you are using an E67 ECM and LS2 throttle body. Shouldn't make much difference that you are using LS4 programming.
FYI - your accelerator pedal position sensor has 6 wires. 2x grounds, 2x 5-volt references, and 2x signal wires (in case they need to know). This is the SAME as the LS2 and many other LS DBW applications.
[This message has been edited by Darth Fiero (edited 07-19-2013).]
Since using an aftermarket ECU is a requirement, I have to assume it won't communicate with the GM TCM that runs the 4T65-E trans in this swap WHICH MEANS you would also need to buy an aftermarket transmission controller (TCU). Sounds like using the aftermarket stuff is going to be quite expensive (and I bet the aftermarket modules are nowhere near as reliable or capable as the factory GM modules – based on the past experience I’ve had with them).
I think it would be cheaper to just install a GM electromotive cruise control unit to actuate the accelerator pedal in this swap directly.
Not sure of the price for the aftermarket stuff, but the GMPP stuff cost me $1K. I got the ECM, Harness, DBW gas pedal, and some other small stuff. In the end I had to dump the stock GMPP ECM and get a "known good" ECM from S&P. The stock tune from GM didn't work, car would not idle.
Not sure of the price for the aftermarket stuff, but the GMPP stuff cost me $1K. I got the ECM, Harness, DBW gas pedal, and some other small stuff. In the end I had to dump the stock GMPP ECM and get a "known good" ECM from S&P. The stock tune from GM didn't work, car would not idle.
Rob
It is funny you bring up the GMPP stuff - I worked on a 57 Chevy a few years ago that had a LS3 crate motor and 4L65-E crate GM transmission in it. Everything including the wiring and computers were purchased from GMPP. GMPP sold this guy a production E67 ECM with GMPP programming on it and a stand-alone TCU. The TCU looked like it was based on 80's technology and did not resemble any production GM module. The TCU did not communicate at all with the E67 ECM and it had VERY LIMITED tuning and diagnostic capabilities. Why GMPP didn't/couldn't sell a production T42 GM TCM in this kit is beyond me. The TCU did come with software so the end-user could adjust the shift points and shift firmness settings, but as I said, it was quite limited. There was almost no diagnostic capability, whatsoever.
Probably $2000 - $3000 for an aftermarket ECU, TCU, and wiring harness(es) - not including the cost of custom tuning which would need to be done after installation.
I'm sure the aftermarket does NOT make an aftermarket ECU and TCU that will plug right into a factory production harness.
As will I. My 88 coupe didn't even come from GM with CC, so not only will I have to figure out the software side of it, I have to upgrade the steering column.
I did not use a BCM in this swap. Unfortunately, with it missing, the cruise control refuses to work (cruise control switch wires directly up to the ECM). The ECM is looking for a BPP (brake pedal position) sensor signal from the BCM - which there is none. The BPP only hooks up to the BCM in the LS4 applications. There is a stop lamp switch wire that hooks up to both the ECM and TCM and I have that hooked up (using the stock Fiero brake switch). Neither the ECM or TCM throws a code for a brake switch signal but the ECM must want to see BPP sensor status before it will enable cruise control operation. Reading ECM data with the Tech2 it shows BPP sensor status as "invalid" and thus cruise control operation is prohibited. TCC still works though.
I had a work-around planned using a stand-alone GM electromotive cruise control module hooked up to actuate the accelerator pedal assembly but the customer opted to NOT have me pursue that option.
FWIW: The BCM wasn't a mess in the 1st LS4 swap I did either - it served its purpose and worked for everything that customer wanted it to do.
Evidently the older E-40 ECM (05,06) Doesn't need a BPP signal to enable the CC to operate. I was able to wire mine directly to the ECM and it works fine.
Evidently the older E-40 ECM (05,06) Doesn't need a BPP signal to enable the CC to operate. I was able to wire mine directly to the ECM and it works fine.
If that is indeed the case, that's great news for guys using Gen3 LS4 engines but doesn't help those who have the Gen4 engines.
Cool looking car! What place is that behind the car with the rockets and tanks? Located in Texas?
That pic was taken during NTFC Spring Fling event two weeks ago in Oklahoma, specifically at Fort Sill. The field artillery base, we went to a museum there and I snuck off and took some pics.
Originally posted by infinitewill: Lookin' good Tom! I went and visited my beast last week in Coeur d"Alene. Jon Lagler did an amazing job on the original build and Joe Sokol has made even more great mods. Yours and mine are nearly twins
Dr. W.
can't wait to see yours in person. hopefully you can make it down for Ruckus in October. i believe it's in Abilene this year.
Another update, got my car ready to go to AAFO/BCF Round-Up in New Braunfels. I redipped my car to a Radiant Red Pearl and installed a very nice set of tail lights. Before:
Not before accident pic but in the shade.
After:
I got rear ended at a busy intersection where I made a left hand turn, as soon as I made the turn traffic was stop (backed up). The jeep behind made the turn while it was light was red and couldn't stop in time and hit me which pushed me into the car in front of me. The rear bumper has a couple of tears. The front bumper has a crinkle in it hard to see in the pic along with an impression of license plate.
So I'm in the market of some very nice GT taillights, rear and front bumper. Lmk...
Thanks...
[This message has been edited by Tom Slick (edited 08-15-2020).]
I may have a perfect red GT front bumper (I am hoping to pick up my car the week after next) as I will be installing my i512 nose from Rob. I also have a near perfect set of GT tail light lenses that I "might not" need depending on the condition of those on the new car. I'll call you when I know something.
Dr. W.
Thanks Will. Taillights are high priority for me right now. Still interested in the nose.
What was done to keep the elements off of the ecm and other parts. Plus what was done to keep the air cleaner from getting dirty? When I got my car PO had the air cleaner installed the same. I had to wash it many times to keep clean. That are attracts a lot of dirt, water etc. Currently I have moved it and it is staying clean.
[This message has been edited by solotwo (edited 04-29-2014).]
Originally posted by solotwo: Any rubbing problems with the 18's in the rear? My car has 18x9's in the rear and once in a while the tires rub on the wheel wells.
No rubbing issues. I have coilovers with 325# springs. I can probably still drop it a little but haven't fine tuned the rear suspension.
What was done to keep the elements off of the ecm and other parts. Plus what was done to keep the air cleaner from getting dirty? When I got my car PO had the air cleaner installed the same. I had to wash it many times to keep clean. That are attracts a lot of dirt, water etc. Currently I have moved it and it is staying clean.
The ECM and TCM have weather sealed connectors so there is no reason to fear contamination by the elements.
I have the air filter in my own Fiero mounted in the exact same location as where I put the one (shown in the above picture) in this LS4 swap. Do they get dirty? Yes. But I find I only have to clean the air filter about once a year - although I will admit I rarely drive drown dusty or gravel roads.
I don't know where you think you are going to mount an open element air filter in a Fiero where it isn't ever going to see dirt or moisture exposure. I can drive down a dusty or gravel road one time and then pop the decklid on my Fiero and find a inch of dust and dirt covering my engine. So if you think that by mounting an open element air filter inside the engine compartment is going to protect it from dirt and moisture - you are mistaken. Likewise if I get caught in a rainstorm, I find a great deal of moisture making it onto the surfaces of the engine and everywhere in the engine compartment (except in those areas that dry quickly due to their exposure to exhaust heat).
Bottom line: if you live down a gravel road or travel dirty roads regularly, you are going to see elevated levels of dirt and debris being captured by your air filter no matter where it is mounted. The nice thing about K&N filters is the more dirty they get, the better their filtration ability.
If you are that worried about dirt and moisture inundating the air filter, then perhaps you should reinstall the stock Fiero 2.8 air filter canister and water separator and then sacrifice a ton of performance by forcing the engine to breathe thru those bottlenecks. Sure, you can mount an open element air filter right onto the throttle body but then you are sacrificing a significant amount of performance by forcing the engine to breathe in heated engine compartment air.
What was done on this LS4 swap concerning the induction system was done to attain the best performance possible. If the filter does its job properly, there should be very little risk to the engine's health over its expected service life. Of course, if the owner decides to drive thru high water, it is very possible the air filter could get flooded in its present location. But I would expect that anyone with common sense would try to avoid high water.
SOLOTWO: You do understand that picture was taken without the inner wheel well cover on and that the inner wheel well cover was replaced before the car was driven, correct? I certainly wouldn't recommend anyone with an air filter mounted in the shown location drive without the inner wheel well cover in place.
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[This message has been edited by Darth Fiero (edited 04-30-2014).]
I mounted my N* ECM/TCM much the same way you did on your first LS4 swap but I really like the way you've mounted these. Are these mounted directly to a piece of the metal frame or are they isolated from the frame like the earlier swaps? Enquiring mind need to know.....
