4l80e questions

[Will L.]

Ok tranny wizards: every time I disconnect the batteries for a while the tranny has to relearn the shift points. This used to take 10 or so cycles through the gears. Now since the turbo add on it takes longer. Is he anything I goofed on this? I went through all the grounds twice they are clean and rock solid.

Ip is db2 maybe bumped the tps? I have to search out adjustment procedure to verify. On the tps subject I am on the throttle so hard at hiway speeds I never seem to get Tc lockup, even before turbo addition. Any input appreciated.

 

[WarWagon]

Couple ways to set the TPS. Only one I use is set/adjust the idle then adjust the TPS to get 0.5v between the ground and sense wire on the 3 wire TPS plug. Open the throttle to WOT and it should go to near 5v. If you get 4v you may have a 6.5 TPS on a 6.2 IP. Use an analog voltmeter to see if the TPS drops out or flicks the needle.

Check the 'trans' computer for codes.

On my 1993 the TCC will come on after a time delay in 3rd WOT. I am fuzzy if it did the same in 4th.

A stand alone 4L80E controller is available from Burning oil. it can be programmed to shift and lock the TCC when you want.

 

[billyg38120]

Hello Will L.
I assume your H1 is a 1995 6.5L Diesel with a 4L80-E. Is your System a Mechanical Injector Pump not PCM controlled WITH a TCM controlling the 4L80-E? Or is it a PCM Controlled Pump and trans?
Did you ADD the turbo without any mods to the Trans and Trans controls.
I need to know to correctly answer your question.
Thanks Billy G.

 

[Will L.]

Billy, yes 6.5 original n/a that I added gm-6 turbo with home made turbo master to control waste gate. No pcm only tcm for the 4l80e. Db2 ip. To fit the turbo I removed the Engine speed sensor/Oil pump drive, Replacing it with just an oil pump drive. I made my own crank position sensor so that it was a two wire signal instead of the three-wire signal factory crank position sensor to send signal to the TCM.

I was thinking about adding a toggle switch to do the TCC lockup mod just to see if I can tell a difference when I'm at freeway cruising speeds. The only reason I haven't done it is i heardof a few people that added it then had problems with the transmission afterward.

 

[just a number]

when you relocated to pickup sensor did you take into account the 2:1 difference is the speed. 2 rpm crank speed is only 1rpm for the cam shaft. that might be part of the problem.

 

[billyg38120]

Billy, yes 6.5 original n/a that I added gm-6 turbo with home made turbo master to control waste gate. No pcm only tcm for the 4l80e. Db2 ip. To fit the turbo I removed the Engine speed sensor/Oil pump drive, Replacing it with just an oil pump drive. I made my own crank position sensor so that it was a two wire signal instead of the three-wire signal factory crank position sensor to send signal to the TCM.

I was thinking about adding a toggle switch to do the TCC lockup mod just to see if I can tell a difference when I'm at freeway cruising speeds. The only reason I haven't done it is i heardof a few people that added it then had problems with the transmission afterward.

Will L.
As the Gentleman asked below did you take into account the Engine Spd Sensor is actual from the camshaft sensor? It has 2 pulses per rev and the TCM is calibrated to run this way.
If the pulse is incorrect you can set TCC Codes and maybe in 3rd Gr at Highway spds. You should invest into or Borrow a Scan Tool to look at CODES AND the Engine RPM.

I can help you with the extra power from the engine AND the Trans calibration. (I am retired GM 4L80-E cal eng) I use the same TCM in my 77 crew cab with a 7.4L with EFI and a 89 ECM. But some items must be found out first.

Some things I have learned: I would NOT elevate the trans pressure via a spring or resistor or another means. Most add additional pressure @ IDle which drags the converter clutch and will wear out the plate. In 97 we made a running change along with a Sol B code change to the old TCM. The TCM was used from 94 through 2002 or 3 in P-Trucks. You can run a larger cooler and I would if I were you in NV. Change the fluid in the trans and transfer case yearly. Rinse off the trans filter with brake clean and the bottom of the unit, reinstall the filter IF NO MATERIAL IS PRESENT.
I have never seen anyone, as Hypertech or another , with a cal for the old TCM. To perform the nec pressure increases for your performance gains I would need a copy of your calibration. This can be done by pulling the chip out, loading the chip to a program, and naming it to a file. Email works. I can change it, sind you a list of each cal change and send the old and new one back. I can update the pres @ Idle to lower it as the released cal did and change the Sol B Fail timer. The majority of the changes would be to upshift AND downshift pressures to handle the increased load.
Your TCM or Vehicle DOES NOT LEARN OR ADAPT it's upshifts as other GM controls do and did.
You may elect to run another TCM from another manufacture. I did NOT. Some reasons are Pressure control, diagnostics, and other internals.
Good Luck and I hope I have helped you.
Before you beginanything please pull the trans pan to inspect for any clutch material or burning. If any has taken place NO calibration can help you. You need an over haul.
I use Trans Star overhaul kits, Good Torque Converters, and Delhi electrics.

 

[Will L.]

Yes, the 2:1 ratio is what made it perfect, as the ess signals 8 times per revolution, crank signals 4 times per revolution( thanks again Leroy for that magic bit of info). The only difficulty there was square wave vs sign wave, or 2 wire vs 3 wire, so I hit a hunk yard and pulled half a dozen 2
Wire sensors, used one that was correct length, cut off mounting tab and added on from 6.5 and viola. I verified correct rpm with external tach, all is good there.

The tcc not locking has been like this for a over a decade (since I got the truck). I have kinda been waiting to need a rebuild but 134,000 on the clock and no problems. I am not sure if tcc lock is working or not. I just can't feel it. Kinda hoping its not so I could fix something stupid and enjoy a little lower rpm on the hiway.

If no learn or adapt is in place what is happening after battery disconnect? If battery is undone for more than 5 minutes, when i first start driving it the shift point is about 3250 rpm and shifts hard. After about 10 times going up to 60 mph back to 0, it will shift normally. It has done this since I got the truck, and all the other hummers with db2 I worked on did the same thing, but not the ds4 hummers. I don't recall pickups doing this, but that has been a while.

 

[WarWagon]

Codes? TPS adjustment status? I have had the hard shift with TPS issues on the pickup. (93)

 

[Will L.]

DUH! Knew I forgot to say something. No codes, checked tps adjustment- voltage range good. Watching tach close and going through gears I get 1,2,3 but never feel lockup or see slight drop in rpm after shifting into 3rd.

WW, you mentioned problem from using toggle switch mod. Is there a safe way to test it on hiway without chance of goofing things up? Like : make sure to turn it off before coming down out of third? I don't understand the full function going on here. I r&r parts
In rebuilding a couple of these years ago, but was happy, almost amazed, when it all worked in the end

 

[Burning oil]

Sounds like BillyG has alot of info to offer, welcome to TTS.

I dont know what it is but most of the TCM controlled vehicles I have driven will present the same problem, that being no TC lock up and/or very hard 1-2 shift. If you turn the key off it resets imediately and is fine til next time.
My old 93 did it fairly regular.

 

[WarWagon]

With the mods to your sensors you need to scan the ECM to see what gear is commanded and look at the sensors to see why. Not getting 4th or the TCC not locking when commanded will trip a code, but, no SES light.

I have had trouble with the speed sensor wiring having the insulation fall off by the transmission.

The lockup switch caused me 2 issues.
1) Compression braking in manual 2nd with the TCC locked burned out the over run clutch pack for 2nd. Does not affect going forward.
2) 50K of towing at WOT with the TCC locked and slight power increase, all the GM3 was worth, burned up the TCC clutch requiring a trans overhaul. Your Hummer is heavy enough for this to be a concern.

There is a rumor that 100% duty cycle, aka a switch, on the TCC clutch will stop oil flow through the converter or help heat/overheat it up. Computer only commands 99%. I'd like to know for sure.

 

[Will L.]

Ok, that would make sense. I miswrote I do get 4th gear, just no lockup. When I wrote 1,2,3 I ment shifts. Sorry about that. This has done it before the modification and a few other hummers I drove, rode in. Could be the load like you say. They weigh between 6000 and 11000 depending on outfit. But the gearing may add to that. 2925 rpm is 75 mph nearest I figure.

 

[billyg38120]

Yes, the 2:1 ratio is what made it perfect, as the ess signals 8 times per revolution, crank signals 4 times per revolution( thanks again Leroy for that magic bit of info). The only difficulty there was square wave vs sign wave, or 2 wire vs 3 wire, so I hit a hunk yard and pulled half a dozen 2
Wire sensors, used one that was correct length, cut off mounting tab and added on from 6.5 and viola. I verified correct rpm with external tach, all is good there.

The tcc not locking has been like this for a over a decade (since I got the truck). I have kinda been waiting to need a rebuild but 134,000 on the clock and no problems. I am not sure if tcc lock is working or not. I just can't feel it. Kinda hoping its not so I could fix something stupid and enjoy a little lower rpm on the hiway.

If no learn or adapt is in place what is happening after battery disconnect? If battery is undone for more than 5 minutes, when i first start driving it the shift point is about 3250 rpm and shifts hard. After about 10 times going up to 60 mph back to 0, it will shift normally. It has done this since I got the truck, and all the other hummers with db2 I worked on did the same thing, but not the ds4 hummers. I don't recall pickups doing this, but that has been a while.

You said you verified the RPM with a TACH??? You should VERIFY the ENGINE RPM IS CORRECT WITH A SCAN TOOL. THERE IS NO OTHER WAY. The TCM uses the signal for TCC, diags and other items.
I have seen where others (and aftermarket TCM's) use a toggle Switch to "GROUND" the TCC Solenoid to verify TCC Operation. (If you had a scan tool to verify, the Check Trans light, Data stream, Engine spd, ISS, OSS, Commanded Gear, and NO DTC's or Trouble Codes were set and Trans Temp you could find out or even OVERRIDE TCC with the Scan Tool.
If you must, Grounded the TCC Solenoid wire will NOT hurt any component as you have been told. 99% or 100% you see via the scan too is 100%.
The TCC Apply routine is set to begin at a Duty Cycle (aprox 60%) and RAMP to 100% over a second or so. The Off Mode is done in a similar manner.

 

[billyg38120]

Borrow an old TEch-1 or Tech-1A scan tool from a local dealer or shop. GM Dealer. When you select a vehicle start with a 1995 or 1996 P-Truck DIESEL. This will get you to the TCM selection allowing you to view all you need.
Or if you have a Laptop, MOATES.NET ALDL tool or cable I can send you the TCM files to view the Data stream. It is a VERY WISE investment.
You run this truck with NO idea if TCC is functioning or with NO TCC. I would NOT be running my vehicle on the highway with an open converter for any length of time. I understand the H1's have a large trans cooler and will most likely run open for a while BUT you would NOT like what the ACTUAL OIL TEMP IS INSIDE THE CONVERTER. It is very hard on seals and the rest of the unit. My 77 Crew CAb with tube grill runs 95 degrees C Trans Oil Temp with TCC on at 80 MPH. I have a 1.5" thick 12x12 trans cooler by Long. I have an air scoop under the bumper to scoop air into the frt of the rad and act as a low pres area behind forcing more air through the rad area. I do not use the rad trans cooler. My trans cooler lines exit the case as 3/8" STEEL LINES (not 5/16") with opend up case area for flow, and the lines transition into #8 Parker SS Thick Teflon lined lines into the cooler.
Keep it as cool as possible as the Cooling engineers allow without converting over to a oil over water cooler.

 

[Will L.]

The extrernal tach was a mechanical drive of the harmonic balancer. Its a press mechanical tach accurate to .001 and good up to 50,000 rpm. The only thing that was sending a rpm signal was the modified crank sensor I built. That is what I was verifying. The original ess on the oil pump drive had to be removed to fit the center mount turbo, so there was nothing else for a scanner to read. If my homemade crank sensor was off the scantool wouldn't know it because that is the only signal being generated. I wonder if the Tcm is seeing a clean signal now. It acts the same as always so I think so.

I have been looking for a bidirectional scan tool to work wih the hummer but have only found read only so far I need to get ahold of a vetronics tech 1 with g update. Unfortunately, the later updates or tech 2 doesn't read 95 hummer with 6.5 & db2 pumps (Kind of a am general snafu only 1432 produced and only 950 affected so no fix was created.)

I want to find out about the software for laptops (cant remember name) that I think Leroy sales.

The tcc problem has existed more than a decade before the turbo/ ess-crank sensor mod, so I don't think that is related.
Same with what I thought was "tranny learn" every since I got the truck.

As soon as I can the grounding toggle switch will go in for testing only.

Thanks for the help all, I will let you know what I find, it will probably be a week or 2 though.

 

[NVW]

The extrernal tach was a mechanical drive of the harmonic balancer. Its a press mechanical tach accurate to .001 and good up to 50,000 rpm. The only thing that was sending a rpm signal was the modified crank sensor I built. That is what I was verifying. The original ess on the oil pump drive had to be removed to fit the center mount turbo, so there was nothing else for a scanner to read. If my homemade crank sensor was off the scantool wouldn't know it because that is the only signal being generated. I wonder if the Tcm is seeing a clean signal now. It acts the same as always so I think so.

I have been looking for a bidirectional scan tool to work wih the hummer but have only found read only so far I need to get ahold of a vetronics tech 1 with g update. Unfortunately, the later updates or tech 2 doesn't read 95 hummer with 6.5 & db2 pumps (Kind of a am general snafu only 1432 produced and only 950 affected so no fix was created.)

I want to find out about the software for laptops (cant remember name) that I think Leroy sales.

The tcc problem has existed more than a decade before the turbo/ ess-crank sensor mod, so I don't think that is related.
Same with what I thought was "tranny learn" every since I got the truck.

As soon as I can the grounding toggle switch will go in for testing only.

Thanks for the help all, I will let you know what I find, it will probably be a week or 2 though.

I believe Leroy sells GMTDScantech which is for OBD-1, I wonder if Carcode would work on the Hummer? It has "CAN" protocals.

 

[billyg38120]

The extrernal tach was a mechanical drive of the harmonic balancer. Its a press mechanical tach accurate to .001 and good up to 50,000 rpm. The only thing that was sending a rpm signal was the modified crank sensor I built. That is what I was verifying. The original ess on the oil pump drive had to be removed to fit the center mount turbo, so there was nothing else for a scanner to read. If my homemade crank sensor was off the scantool wouldn't know it because that is the only signal being generated. I wonder if the Tcm is seeing a clean signal now. It acts the same as always so I think so.

I have been looking for a bidirectional scan tool to work wih the hummer but have only found read only so far I need to get ahold of a vetronics tech 1 with g update. Unfortunately, the later updates or tech 2 doesn't read 95 hummer with 6.5 & db2 pumps (Kind of a am general snafu only 1432 produced and only 950 affected so no fix was created.)

I want to find out about the software for laptops (cant remember name) that I think Leroy sales.

The tcc problem has existed more than a decade before the turbo/ ess-crank sensor mod, so I don't think that is related.
Same with what I thought was "tranny learn" every since I got the truck.

As soon as I can the grounding toggle switch will go in for testing only.

Thanks for the help all, I will let you know what I find, it will probably be a week or 2 though.

You can contact "V" for info. The Tech-1 or T-1A is NO longer serviced or sold. No cartridges either. Maybe e-bay. TECH-@ DOES AND WILL COMMUNICATE WITH YOUR OLD HUMMER. Only 1994 forward H-1's though. They ARE the SAME TCM. It was used in Mechanical Pump H1 for a long time and were used in the old Diesel P-Trucks. Plug into the ALDL with the T-2 AND the correct 12 PIN ALDL ADAPRTER. Select the T2 vehicle as a P-Truck with a 6.5L Diesel engine and select along to get the trans. (I've done this many times) IT will work for the DATA LIST, RECORDING AND to functionally test Mode 4 or bi-directional as you say.
You CAN purchase a USB to 12 Pin ALDL cable from Craig Moates at MOATES.NET for about 80 or so. I use TUNER PRO version 5. I have Files for the old TCM that work well and a calibration listing for the most cals I used. No one has these files or has the understanding on the subject.
Just the Moates cable and Tuner Pro is Free if ya can out up with the intro but a $39 dollar donation is worth it. IT will be able to view CODES, CLEAR then and see DATA from the sensors. I did NOT create NAY mode 4 over rides except CLEAR CODES. I don't use them in calibration and understand how it all works.
Y'll be able to see the Engine Speed signal and how the calibration understands it. you can also CHANGE the PULSES PER REV, as I had to from the Diesel cal like you have so it will read the correct RPM.

THE Engine SPD signal can be either a sign wave or DIGITAL Square wave 5 volt. YOU DO HAVE TO CHANGE THE PULSES PER REV from the Diesel to a Gasoline 0-5v sq wave. The same pin reads BOTH. It's in my cal list in Tuner Pro. tunerpro.net and moates.net

 

[Will L.]

Sweet! A trip to Tn, and convincing you to school me could be in my future.:joke: I think I see light at the end of the tunnel for real.

I tried the tech 2, when I was the Mac Tool guy- i took my truck to every gm dealer at the valley auto mall (9 gm dealers) and 6 others in town, along with about a dozen regular shops just trying everyone I could with no luck (its amazing how many techs will help when your the guy with all the chrome they want!) I knew about the p truck thing and also tried as a g van. I took it to the hummer dealer while it was still here, and they already had my vin on file from the p.o. As one of the problem children. They did say a $7500.00 upgrade was available if I was interested in seeing if would help.:yeah: maybe the wrong aldl adapter but even the 2 hd truck shops couldn't get it. Everybody could read just no control. Do you know the adapter id by chance?

If I get the usb adapter I don't follow you on where to go from there.

I spoke to vetronics about it (had to deal with them as a tool guy already) guess how that went.

I really wish i knew trans better- It gets over my head too quick and I just don't have the patience for it. All hummers are automatics, but I sure thought about altering that when I was in limp mode over bad tiss & toss that went out at the same time.

 

[Burning oil]

What sensor are you using on the crank pick up?

 

[Will L.]

There are only 2 types of magnetic sensors square and sign wave or 2 wire and 3 wire.
I copied this from the end of my other thread:

Crank sensor / ess problem: I couldn't find a correct 2 wire sensor so - out of a 97 Mazda b3000 with Ford 3.0 engine I took that 2 wire cps sensor cut off the mounting tabs and ground the end of the sensor down so it would fit in the hole. Then solder wires on the contacts and used 3m - 2 part rubber epoxy to form the back of the sensor and to mount the gm cps mounting tab to the new sensor. I had to use a oring 1 size larger than normal for the ford sensor and my ess has been replaced successfully. Definitely pull the timing cover off to make the modified senseor fit properly.