ewingr

I have had my conversion running for a year and half. Periodically I get a P2138 code. Engine light comes on, pedal stops responding. I have to pull over, and reset codes to get back on the road.

It has been intermittent. I may drive 350 miles with no problem, then all of a sudden it will happen every 2-10 miles.

I replaced the pedal thinking that would fix it. Nope...it did not.

I have a Dakota Digital cruise control, which has a harness that is inserted between the pedal connector and the pedal. I am suspicious of this being the problem. I have pulled that out, leaving no cruise, and will be driving for a while to see what happens. But, to be confident, I'll have to have success for quite a while.

Just wondering if anyone else has run into this and has any thoughts/ideas.

TomM

iTrader: (56)

Seem to recall a thread on here a few months back about that very problem. It was indeed the DD controller for the cruise control. I think the poster called DD and they sent him out another controller with an upgrade to the software.

T,

ewingr

I appreciate the input. I'll do a search to see if I can find that thread.
I've talked dto 3 different DD guys, and keep getting pointed to various things: is your pedal voltages right? Are the voltages on the J4 wires right? Right now they have me on a chase of the grounds, test them to see if they are good.

If I can find more details about what the other poster found, maybe I can get them on the tracks.

TomM

iTrader: (56)

If I recall it was the member with the green Nova with a vinyl top, maybe Billy Fargon? It was way down in his thread after he got the car ready to run.....

T,

TomM

iTrader: (56)

Found it....post 303....might be something to consider....was actually the OBD2 interface, not the cruise...

https://ls1tech.com/forums/conversio...fargon-16.html


T,

ewingr

Really appreciate your help. I couldn't find Billy Fargon...because the user name was billyfargon.

Turns out his problem is completely different. I think the engine was dying. Mine is the pedal stops working, but doesn't kill the engine.

Update
I don't have anything particulary useful to update yet. I talked to Austin at DD, and he is going to check if there has been a firmware update. But then that was a different issue for Billy...so maybe that isn't it.

He wanted to know the specific pedal I have to be sure it is compatible. So, I pulled it and found the part number and have emailed it to him. I'll see what he says about that tomorrow.

I also wrote up an email and sent it to Rostra (they make the DD cruise controls). Maybe they'll have something to offer.

In the meantime, I need to put some miles on it w/o the cruise hooked up and see if it still has the pedal issue.

ewingr

Just to update...
Dakota Digital came back with a suggestion to put the Cruise ground to the purple ground wire in the pedal harness. Problem is, I've had it there since almost the beginning, and this has been going on all that time. Also, my engine harness folks don't like that there, so I have removed it to another ground. (That is PSI Conversions, and they have been VERY GOOD support).

I told DD of that, so they then suggested one of 2 other pedal options. They said the Corvette pedal has been problematic on their cruise controls (CSC 2000). But checking them out, I see they are all plastic. Don 't like that. I called the wiring guy, and he said they are truck pedals, and would require swapping 2 wires for them to work. And, he has sent those types of pedals out a few times, and all users weren't happy with them and ended up with the metal Corvette pedal like I have. He said those 2 lean toward the trans tunnel.

So, so far, no progress. I sent an email to ask if they would consider swapping out the cruise controller. Waiting for reply.

ewingr

Currently driving it w/o the DD Cruise unit hooked into the pedal harness. So far, about 40 - 50 miles on it that way with no P codes.

Dakota Digital is going to send me an exchange unit. First think I plan to do is put in the unit, and if it fails, I'll then change out the harness (much larger job...will need to pull the front of the dash to get to the wires).

I was on a test drive today when the other problem of the engine completely dying started. I suspect you've seen my post on that topic.

I'm certainly having my share of issues.

ewingr

I haven't heard from anyone that is even using the Dakota Digital cruise with their Ls engine.

For anyone interested below is the latest:

The problem has become less intermittent, and can be reproduced regularly. When I am driving, and press the set button on the HND-3 stalk, within less than 5 seconds the computer throws a P2138 code, and the pedal stops operating. Requires that I clear the codes to drive again.

Below is the process I have gone through:

A pattern has come to front
Over the past couple years this has been very intermittent. But now, it happens every time I use the Cruise Control. In fact now it sends the code within 5 seconds after pressing the set button on the HND-3.

What I have done to try to fix the problem
Having identified that the problem is related to setting the cruise, a new unit and harness was sent out. (Old one going in mail tomorrow...oh, today by the time you read this).

Following has been done:

• Replaced old harness. Particular attention was paid to quality of implementation of the harness
• All wires not hooking direct to something were soldered
• Per information from a support rep at Dakota Digital, he wanted me to do a voltage drop test on the grounds. I have done the tests
  • FYI...several important items have been grounded direct to the battery: Air Ride, Push Button Start, Air Conditioner, and several other things
  • All grounds tested gave me the same reading
    • First test the reading was: .0653
      • At this point I added a new 1" ground strap to the back of the head of the engine, which also have the battery ground cable, and the PCM grounds.
      • I shined up a spot on the frame to mount the ground which is in addition to one other 1 ground from trunk to frame
    • Added a ground from a header bolt to the body. This was a small 1/2" strap
    • Pulled the ground straps from the trunk (battery to frame, body to frame), and shined up the metal real good that they ground to (frame)
    • Final test reading was: .040 - .045 (fluctuates)
    • Ground for cruise unit moved to purple gnd wire in the pedal harness.
• I fed the purple speed wire on the cruise module with the VSS wire from the PCM

After all above, a test drive yields the same results: P2138 code happens, and pedal stops operating. Need to clear the code to drive the car.

So, at this point I tried one other thing: I cut the VSS wire from the purple speed wire in the cruise, and hooked a wire from the SPD OUT port of the Dakota Digital gauge system 1961- 62 Chevy Impala Digital Instrument System, which according to the instructions is for feeding a cruise control. The results were surprising: The cruise control will not set at all. When I push the set button the C cruise indicator in the gauges flashes on, then off. No working cruise.

One other note: Last year when this problem was more intermittent, I installed a SEN-4165 magnetic pulse which was no help to the problem. I have abandoned that. Also, as FYI...I replaced the pedal with a new one. (GM# 25835421 - Corvette medal pedal) and it made no difference. Austin at Dakota Digital did suggest I try a different pedal, for which he gave me 2 numbers. I spoke with the harness builder and he said they had sent out a few harnesses with that pedal, and in every case the customer was not happy with them ...all plastic, and strange angle leaning toward the transmission hump. So, I am reluctant to change the pedal.

Final status
So currently the cruise in inoperable based on using the SPD-OUT wire from the gauge control box.. An interesting note: When using the RSS feed to the cruise, the cruise will set at 20 mph (and of course then send the P2138 code). I understand it should not set at 20 mph. But then when using the SPD-OUT the cruise is inoperable.

I'm afraid I may have to abandon the cruise control.

I have sent the above info to Dakota Digital, and to Rostra (they make DD's crduise). I'm reaching for help with this wherever I may get it. I hope a resolution can be found.

Michael Yount

iTrader: (1)

New crate LS3 with 08 Corvette ecu, PSI Conversions supplied harness and used ecu. DD cruise control with speed signal provided by 2 magnets on the driveshaft. All worked flawlessly since I first fired it up over 3 years ago. Read through your issues - sorry nothing comes to mind...

ewingr

Thanks for the input, Michael.

I did try the magnet at driveshaft route last year. Didn't help me. Maybe I should try it again... It's still at the driveshaft.

Question: what pedal are you using? If it is metal it's probably a Corvette pedal. DD did request that I try a truck plastic pedal. I'm reluctant to do that. Would be good to know if the metal Corvette pedal is working.

I presume you are drive by wire, no?

Michael Yount

iTrader: (1)

Metal Corvette pedal - yes, DBW -- I insisted that PSI give me "matched" components to try and eliminate the often weird operating crap that seems to pop up regularly when people try to slopify a junkyard parts inspired swap -- clearly not the approach you've taken; you seem to have things well in hand! So they provided the mass air sensor, O2's, wiring harness, ecu (sans rear O2 and other emissions functions) and gas pedal. Car started on the first turn of the pedal and settled into a 675 rpm idle. Installed the DD cruise (the folks at Rostra tech were VERY helpful; the folks at DD tech - not so much) a couple of months later and it worked as well as the OEM units in our newer daily drivers from the first punch of a button. The folks at Rostra were able to help me configure things so that I could use my existing cruise control switch to operate the new unit.

The magnets (I use 2 180-degrees apart) and pickup were supplied by Rostra as part of the previous Rostra-universal unit I used with the cable-operated throttle 5.0L that was in the car before the LS3. I simply grounded one side of the 2-wire harness and connected the other wire to the speed input wire on the DD harness as directed by the instructions and the folks at Rostra. It doesn't sound to me like that's your problem.

ewingr

Actually, I went the same way you did with PSI. I'm not sure what you based your opinion that I didn't do the same on, other than the fact I'm having so much trouble with the cruise.

From a support perspective I've been working with DD, Rostra, and Gary at PSI.

Another question for you: did they have you put the ground wire from the cruise unit spliced into the purple ground wire in the pedal harness?

Michael Yount

iTrader: (1)

You're seeing something in my previous comment that was unintended -- when I said I thought you had things well in hand, I meant you had been very thoughtful in the way you put things together. That's part of the reason that I'm scratching my head about what the problem might be. Lots of support from Gary and the guys at Rostra for me too. I gave up pretty quickly on the guys at DD - they were not helpful for me.

Memory is often questionable at my age -- but my recollection is that I grounded the cruise unit directly into my chassis/unibody. My only questions of DD had to do with using my existing magnets/pickup as the speed input. I finally got clear direction on that question from the guys at Rostra.

ewingr

Oh, sorry for the misunderstanding.

I had a question at the end if like to hear an answer to:

Did they have you put the ground wire from the CRC-2000 unit into the purple wire in the pedal harness? The purple wire is one of two ground wires in that harness.

Michael Yount

iTrader: (1)

No problem. I answered your ground question in my previous post. “Memory is often questionable at my age -- but my recollection is that I grounded the cruise unit directly into my chassis/unibody.”

ewingr

Sorry. I'm a dork. I didn't read it all apparently.

​​​​​​They, DD and especially Rostra, have told me to hook the ground for the cruise into that purple wire. However talking with Gary at PSI... He does not like any messing in that pedal harness... Especially cutting and soldering.

An interesting thing... The cruise will enable at 20 mph, which it's not supposed to do . This of course is if I have the VSS wire feeding the cruise for speed.

I appreciate all of your input. Over the next couple of days I may reimplement the magnet system for speed input. Didn't help in the past but the system has had a thorough going over to improve the wiring.

As a note of interest, when I was putting in the new harness I found a wire that was hooked to the black VSS wire by connectors easily pull out of the connector... at both ends. I thought sure I had found my problem. After replacing all connectors in the install with solder, it wasn't too be so. Good thing I didn't have any money down at Vegas for that

Michael Yount

iTrader: (1)

Two thoughts - 1) maybe 20 mph actual speed isn’t what the system thinks is 20 mph; 2) “VSS wire” - the wire straight from the pickup? Or the speedo output from the ecu/system after it’s processed the VSS signal?

Other than question to Rostra about speed signal, I just hooked it up per the instructions - and it worked.

ewingr

I'm not sure what the answer is regarding the VSS signal. All I know for sure is that it is the black wire that comes in the PSI harness, labeled as VSS. Going to memory right now, but I think it says it can be used to signify speed. So itt was hooked up actually two two things: the cruise control, and to the gauge set providing the speed in the gauges. Maybe there is something I'm missing about calibrating at between 4K and 8K. I don't recall any instructions about that, but we'll see if something comes up.

Michael Yount

iTrader: (1)

Suspect that any wire in the PSI harness is the speed signal coming OUT of the ecu after the VSS signal going IN to the ecu has been processed. I have my VSS going into the ECU and a separate speed signal (from magnet/pickup/driveshaft) running the DD cruise. It oughta take the speed signal from the ecu. But I wonder if you can “split” that signal for use by both the speedo and the cruise. I just don’t know.