Dirtflirt

I am retro fitting a 2005 LS2 into a 71 K5 Blazer, it is DBW and I have an issue, the engine will crank and run you can blip the throttle about three times and then the throttle goes dead. My source was kind enough to let me hang out at his shop and try swapping out the throttle petal, the tach module, the PCM and the throttle actuator itself all to no avail. I have two 4G grounds on the block to the frame and triple checked the grounds for the harness. This setup is for a manual trans so I believe that there has been some wires deleted. I believe that the harness came off of a 2004 because the oil sender was slightly different.

Has anybody had or heard of this. I am pulling my hair out.

Thank you in advance.
I spent 5 hours reading here looking for FAQ's and issues and did not find anything related so if it is here already and I missed it my apologies.

garys 68

iTrader: (1)

Sounds like a pedal/wiring mismatch. I didn't think 05 LS2s from corvettes or GTOs had TACs, so is yours from a TBSS?
Also list the details of the harness, ecu, pedal, etc

Old Geezer

iTrader: (3)

Setting a code[s]??

oberth1

iTrader: (6)

have you tried it with a manual throttle? VATS is off, correct?

chuckd71

iTrader: (23)

What are these parts coming out of? Different vehicles switch parts during different years.

Dirtflirt

the engine came out of a 05 2500 HD LQ4 the harness is out of an 04, 2500 HD the guy that hooked me up has a fleet of gen III powered old Chevy muscle cars and trucks.

I have a manual trans, the harness is bare bones converted, I did not get a check engine light, EGR, VATS and all other non Vital systems are gone.

I am a noob to this site so some of the abbreviations are not familiar to me, I figured some of them out.

Dirtflirt

a manual throttle will need a different reluctor ring wouldn't it.

garys 68

iTrader: (1)

OK, good start, we've got something to work with. It's an LQ with a 3 bolt TB, not an LS2 with 4 bolt, correct?
Whay TB do you have?
Is the ecu a 463?
What TAC is it, plastic with metal ends?
What pedal are you using? APPS part number will help.
Where did you get the TAC to pedal harness?

psiconversion

iTrader: (5)

Second every question Gary just asked as this will help us determine what you problem is.

Jon
PSI

chuckd71

iTrader: (23)

No, at least not necessarily. I went from dbw to dbc on mine without changing it, just had to change something in the computer.

psiconversion

iTrader: (5)

Chuck, what ECM were you using in your conversion?

Jon
PSI

chuckd71

iTrader: (23)

Not sure, I'll have to take a look at it next time I go out to the garage. I got it with a harness from chevythuder, and it ran both my Lq9 and LS1.
This is what the guy who set it up said about the changing the comp from dbw to dbc - What I found was a table that is marked "installed options matrix vs platform type". Under platform "7" for the type of engine, the column for ETC was set as "1" instead of "0".

I don't know what it means but it works.

psiconversion

iTrader: (5)

I would have thought you would just put a new OS in the PCM. Let me know what pcm when you have a chance if you dont mind. Thanks.

Jon
PSI

Dirtflirt

it is a 3 bolt TB, the computer has a c24 on the upper right corner, the sticker on the back says hardware # 12589163 yhzs

Dirtflirt

the TAC has the metal base plate, the pedal has a number in the plastic pet 6f50, the jumper harness between the two came from a salvage yard along with the rest of the harness and engine.

Dirtflirt

My bad PBT GF50 so far the app patch is useless

99VetteFRC

I think I remember something about throttle calibration. In a stock situation when a part of the throttle system(pedal, TAC of throttle body) there is a procedure for calibrating. I'm not sure if the HP Tuners can do it or not.

garys 68

iTrader: (1)

Ok, I'm guessing you meant 12569162 for HDW number which is a 463 serv no. That should work on an 03-05 truck with DBW. That ecu does need a TAC and it sounds like you've got the correct metal base one.
I'm not sure on the pedal without the complete part number. You might want to check out Rockauto to see if you have the correct pedal.
If I had to guess, I would think it's the TAC to pedal harness. That's generally part of the body harness and it's pretty rare to get one out intact. You might confirm with a wiring diagram or just buy a standalone TAC/Pedal harness. I think psi has those.

Dirtflirt

I did get the jumper from the pedal to the tac, the guy that hooked me up used to own a few junk yards. I have ran continuity on the pins.

The guy that built the harness is going to make a house call, a very rare event my buddy tells me.

psiconversion

iTrader: (5)

Dirt,

Is there a truck tune in the PCM? Can you post a picture of the pedal?

Jon
PSI